UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-K
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the Fiscal Year Ended December 31, 20162017
Commission file number 1-5153
Marathon Oil Corporation
(Exact name of registrant as specified in its charter)
Delaware 25-0996816
(State or other jurisdiction of incorporation or organization) (I.R.S. Employer Identification No.)
5555 San Felipe Street, Houston, TX 77056-2723
(Address of principal executive offices)
(713) 629-6600
(Registrant’s telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
Title of each class Name of each exchange on which registered
Common Stock, par value $1.00 New York Stock Exchange
 Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.  Yes þ No o
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.  Yes  o No  þ
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15 (d) of the Securities Exchange Act of 1934 during the preceding 12 months and (2) has been subject to such filing requirements for the past 90 days.  Yes þ No o
Indicate by check mark whether the registrant has submitted electronically and posted on its corporate web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).  Yes þ No o
Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.  þ

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company, or an emerging growth company. See definitionthe definitions of "large accelerated filer," "accelerated filer", "smaller reporting company," and "smaller reporting"emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer þ
Accelerated filer o
Non-accelerated filer o
(Do not check if a smaller reporting company)
Smaller reporting company o
Emerging growth company o
Large accelerated filer  ☑    Accelerated filer  ☐If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o    Non-accelerated filer  ☐Smaller reporting company  ☐
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).  Yes  oNo   þ
The aggregate market value of Common Stock held by non-affiliates as of June 30, 2016: $12,6962017: $10,050 million. This amount is based on the closing price of the registrant’s Common Stock on the New York Stock Exchange on that date. Shares of Common Stock held by executive officers and directors of the registrant are not included in the computation. The registrant, solely for the purpose of this required presentation, has deemed its directors and executive officers to be affiliates.
There were 847,201,196849,755,866 shares of Marathon Oil Corporation Common Stock outstanding as of February 15, 2017.14, 2018.
Documents Incorporated By Reference:
Portions of the registrant’s proxy statement relating to its 20172018 Annual Meeting of Stockholders, to be filed with the Securities and Exchange Commission pursuant to Regulation 14A under the Securities Exchange Act of 1934, are incorporated by reference to the extent set forth in Part III, Items 10-14 of this report.


MARATHON OIL CORPORATION
Unless the context otherwise indicates, references to "Marathon Oil," "we," "our" or "us" in this Annual Report on Form 10-K are references to Marathon Oil Corporation, including its wholly owned and majority-owned subsidiaries, and its ownership interests in equity method investees (corporate entities, partnerships, limited liability companies and other ventures over which Marathon Oil exerts significant influence by virtue of its ownership interest).
Table of Contents
 


 
 
    
 
    
 
    
 
    
 
    
 
   
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
   
 
    
 
    
 
    
 
    
 
   
 
    
 
    
  

Definitions
Throughout this report, the following company or industry specific terms and abbreviations are used.
AMPCO – Atlantic Methanol Production Company LLC, a company located in Equatorial Guinea in which we own a 45% equity interest.
AOSP – Athabasca Oil Sands Project, an oil sands mining, transportation and upgrading joint venture located in Alberta, Canada, in which we holdheld a 20% non-operated working interest.
bbl – One stock tank barrel, which is 42 United States gallons liquid volume.
bcf – Billion cubic feet.
boe – Barrels of oil equivalent.
btu – British thermal unit, an energy equivalence measure.
Capital Development Program – Includes capital expenditures, cash investments in equity method investees and other investments, exploration costs that are expensed as incurred rather than capitalized, such as geological and geophysical costs and certain staff costs, and other miscellaneous investment expenditures.
DD&A – Depreciation, depletion and amortization.
Development well – A well drilled within the proved area of an oil or natural gas reservoir to the depth of a stratigraphic horizon known to be productive.
Downstream business – The refining, marketing and transportation operations, spun-off on June 30, 2011 and treated as discontinued operations.
Dry well – A well found to be incapable of producing either oil or natural gas in sufficient quantities to justify completion.
E.G. – Equatorial Guinea.
EGHoldings – Equatorial Guinea LNG Holdings Limited, a liquefied natural gas production company located in E.G. in which we own a 60% equity interest.
EIA – United States Energy Information Agency.
EPA – United States Environmental Protection Agency.
E&P - Exploration and production.
Exploratory well – A well drilled to find oil or natural gas in an unproved area or find a new reservoir in a field previously found to be productive in another reservoir.
FASB – Financial Accounting Standards Board.
FPSO - Floating production, storage and offloading vessel.
Henry Hub price - a natural gas benchmark price quoted at settlement date average.
IRS – United States Internal Revenue Service.
LNG – Liquefied natural gas.
LPG – Liquefied petroleum gas.
Liquid hydrocarbons or liquids – Collectively, crude oil, synthetic crude oil, condensate and natural gas liquids.
LLS – Louisiana Light Sweet crude oil, an oil index benchmark price as per Bloomberg Finance LLP: LLS St. James.
Marathon Oil – Marathon Oil Corporation and its consolidated subsidiaries: the company as it exists following the June 30, 2011 spin-off of the downstream business.refining, marketing and transportation operations.
mbbld – Thousand barrels per day.
mboed – Thousand barrels of oil equivalent per day.
mcf – Thousand cubic feet.
mmbbl – Million barrels.
mmboe – Million barrels of oil equivalent.

mmbtu – Million British thermal units.
mmcfd – Million stabilized cubic feet per day.
mmta – Million metric tonnes per annum.

MPC Marathon Petroleum Corporation – the separate independent company, which owns and operates the downstream business.refining, marketing and transportation operations.
mt – metric tonnes
mtd Thousand metric tonnes per day.
Net acres or Net wells – The sum of the fractional working interests owned by us in gross acres or gross wells.
NGL or NGLs – Natural gas liquid or natural gas liquids, which are naturally occurring substances found in natural gas, including ethane, butane, isobutane, propane and natural gasoline, thatwhich can be collectively removed from produced natural gas, separated into these substances and sold.
NYMEX - New York Mercantile Exchange.
OECD – Organization for Economic Cooperation and Development.
OPEC – Organization of Petroleum Exporting Countries.
Operational availability A term used to measure the ability of an asset to produce to its maximum capacity over a specified period of time, after consideration of internal losses.
Productive well – A well that is not a dry well. Productive wells include producing wells and wells that are mechanically capable of production.
Proved developed reserves – Proved reserves that can be expected to be recovered through existing wells with existing equipment and operating methods or for which the cost of the required equipment is relatively minor compared to the cost of a new well and through installed extraction equipment and infrastructure operational at the time of the reserves estimate if the extraction is by means not involving a well.
Proved reserves – Proved crude oil and condensate, NGLs, natural gas and our historical synthetic crude oil reserves are those quantities of crude oil and condensate, NGLs, natural gas and synthetic crude oil, which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty to be economically producible from a given date forward, from known reservoirs, and under existing economic conditions, operating methods, and government regulations-prior to the time at which contracts providing the right to operate expire, unless evidence indicates that renewal is reasonably certain, regardless of whether deterministic or probabilistic methods are used for the estimation. The project to extract the hydrocarbons must have commenced or the operator must be reasonably certain that it will commence the project within a reasonable time.
Proved undeveloped reserves – Proved reserves that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion or through installed extraction equipment and infrastructure operational at the time of the reserves estimate if the extraction is by means not involving a well.recompletion. Undrilled locations can be classified as having proved undeveloped reserves if a development plan has been adopted indicating that they are scheduled to be drilled within five years, unless the specific circumstances justify a longer time. Reserves on undrilled acreage shall be limited to those directly offsetting development spacing areas that are reasonably certain of production when drilled, unless evidence using reliable technology exists that establishes reasonable certainty of economic producibilityviability at greater distances.
PSC – Production sharing contract.
Quest CCS – Quest Carbon Capture and Storage project at the AOSP in Alberta, Canada.
Reserve replacement ratio – A ratio which measures the amount of proved reserves added to our reserve base during the year relative to the amount of liquid hydrocarbons and natural gas produced.
Royalty interest – An interest in an oil or natural gas property entitling the owner to a share of oil or natural gas production free of costs of production.
SAGE – United Kingdom Scottish Area Gas Evacuation system composed of a pipeline and processing terminal.
SAR or SARs – Stock appreciation right or stock appreciation rights.
SCOOP – South Central Oklahoma Oil Province.
SEC – United States Securities and Exchange Commission.

Seismic – An exploration method of sending energy waves or sound waves into the earth and recording the wave reflections to indicate the type, size, shape and depth of subsurface rock formation (3-D seismic provides three-dimensional pictures and 4-D factors in changes that occurred over time).
STACK – Sooner Trend, Anadarko (basin), Canadian (and) Kingfisher (counties).
TD - Total depth or the bottom of a drilled hole.
Total proved reserves – The summation of proved developed reserves and proved undeveloped reserves.
U.K. – United Kingdom.
U.S. – United States of America.

U.S. resource plays – Consists of our unconventional properties in the Oklahoma, Eagle Ford, Bakken and Northern Delaware.
U.S. GAAP – U.S. Generally Accepted Accounting principles generally accepted in the U.S.
WCS – Western Canadian Select, an oil index benchmark price with monthly pricing based upon average adjusted for differentials unique to western Canada.
Working interest – The interest in a mineral property, which gives the owner that share of production from the property. A working interest owner bears that share of the costs of exploration, development and production in return for a share of production. Working interests are sometimes burdened by overriding royalty interests or other interests.
WTI – West Texas Intermediate crude oil, an oil index benchmark price as quoted by NYMEX.


Disclosures Regarding Forward-Looking Statements
This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934. These are statements, other than statements of historical fact, that give current expectations or forecasts of future events, including without limitation: our operational, financial and growth strategies, including drilling plans and projects, planned wells, rig count, inventory, seismic, exploration plans, maintenance activities, drilling and completion improvements, cost reductions, non-core asset sales, and financial flexibility; our ability to successfully effect those strategies and the expected timing and results thereof; our 20172018 capital development program and the planned allocation thereof; planned capital expenditures and the impact thereof; expectations regarding future economic and market conditions and their effects on us; our ability and strategies to manage through the lower commodity price cycle; our financial and operational outlook, and ability to fulfill that outlook; our financial position, balance sheet, liquidity and capital resources, and the benefits thereof; resource and asset potential; reserve estimates; growth expectations; and future production and sales expectations, and the drivers thereof. In addition, many forward-looking statements may be identified by the use of forward-looking terminology such as “anticipates,” “believes,” “estimates,” “expects,” “targets,” “plans,” “projects,” “could,” “may,” “should,” “would” or similar words indicating that future outcomes are uncertain. While we believe that our assumptions concerning future events are reasonable, we can give no assurance that these expectations willmay not prove to be correct. A number of factors could cause results to differ materially from those indicated by such forward-looking statements including, but not limited to:
conditions in the oil and gas industry, including supply/supply and demand levels for crude oil and condensate, NGLs and natural gas and synthetic crude oil and the resulting impact on price;
changes in expected reserve or production levels;
changes in political or economic conditions in the jurisdictions in which we operate, including changes in foreign currency exchange rates, interest rates, inflation rates, and global and domestic market conditions;
risks relating to our hedging activities;
capital available for exploration and development;
drilling and operating risks;
well production timing;
availability of drilling rigs, materials and labor, including the costs associated therewith;
difficulty in obtaining necessary approvals and permits;
non-performance by third parties of their contractual obligations;
unforeseen hazards such as weather conditions, acts of war or terrorist acts and the governmental or military response thereto;
cyber-attacks;
changes in safety, health, environmental, tax and other regulations;
other geological, operating and economic considerations; and
other factors discussed in Item 1. Business, Item 1A. Risk Factors, Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations, Item 7A. Quantitative and Qualitative Disclosures About Market Risk, and elsewhere in this report.
All forward-looking statements included in this report are based on information available to us on the date of this report. Except as required by law, we assume no duty to revise or update any forward-looking statements whether as a result of new information, future events or otherwise. All subsequent written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained throughout this report.




PART I
Item 1. Business
General
Marathon Oil Corporation (NYSE: MRO) is an independent exploration and production company based in Houston, Texas, focused on U.S. unconventional resource plays with operations in North America,the United States, Europe and Africa. Our corporate headquarters is located at 5555 San Felipe Street, Houston, Texas 77056-2723 and our telephone number is (713) 629-6600. Each of our threetwo reportable operating segments isare organized and managed based upon both geographic location and the nature of the products and services it offers.offered. The threetwo segments are:
North AmericaUnited States E&P – explores for, produces and markets crude oil and condensate, NGLs and natural gas in North America;the United States;
International E&P – explores for, produces and markets crude oil and condensate, NGLs and natural gas outside of North Americathe United States and produces and markets products manufactured from natural gas, such as LNG and methanol, in E.G.; and
Oil Sands Mining – mines, extracts and transports bitumen from oil sands deposits in Alberta, Canada, and upgrades the bitumen to produce and market synthetic crude oil and vacuum gas oil.
We were incorporated in 2001.
Our strategy is to deliver competitive returns by focusing on the lowest cost, highest margin U.S. resource plays while maintaining a peer-leading balance sheet. See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations, for a more detailed discussion of our operating results, cash flows and outlook, includingliquidity.
We are concentrated on our 2017 Capital Program.
core operations in our U.S. unconventional resource plays and E.G. The map below shows the locations of our worldwide operations.core operations:




* Our additional locations include the Gulf of Mexico, U.K., Libya, Gabon and the Kurdistan Region of Iraq.
Segment and Geographic Information
In the second quarter of 2017, we closed on the sale of our Canadian business which includes our Oil Sands Mining segment and exploration stage in-situ leases. The Canadian business is reflected as discontinued operations in all periods presented. Additionally, we have renamed our North America E&P segment to United States E&P segment, effective June 30, 2017. See Item 8. Financial Statements and Supplementary Data – Note 1 to the consolidated financial statements for further detail. For reportable operating segment and geographic financial information, see Item 8. Financial Statements and Supplementary Data – Note 76 to the consolidated financial statements.
In the following discussion regarding our North AmericaUnited States E&P and International E&P and Oil Sands Mining segments, references to net wells, acres, sales or investment indicate our ownership interest or share, as the context requires.
North America
United States E&P Segment
We are engaged in oil and gas exploration, development and production activities in the U.S. Our primary focus in the North AmericaUnited States E&P segment is concentrated within our threefour high quality unconventional resource plays. See Item 7.  Management’s Discussion and Analysis of Financial Condition and Results of Operations for further detail on current year results.
North AmericaUnited States E&P-- Unconventional Resource Plays
Oklahoma Resource BasinsEagle Ford – We hold approximately 365,000 net surface acres and includes 61,000 net acres added in the PayRock acquisition in the STACK Meramec play during 2016. In the SCOOP and STACK areas we hold net acres with rights to the Woodford, Springer, Meramec, Osage, Oswego, Granite Wash and other Pennsylvanian and Mississippian plays. Our primary 2017 focus will be in the Meramec play in the STACK and the Woodford and Springer plays in the SCOOP.  
Eagle Ford - We hold approximately 145,000 net acres in south Texas where we have been operating in the South Texas Eagle Ford play since 2011.2011, where roughly two thirds of our acreage is located in Karnes County and Atascosa County. We operate more than 1,365 gross (962 net) producing wells, 32 central gathering and treating facilities and approximately 865 miles of gathering pipeline inacross the Eagle Ford.field that support more than 1,500 producing wells. We also own and operate the Sugarloaf gathering system, a 42-mile natural gas pipeline through the heart of our acreage in Karnes, Atascosa and Bee Counties of south Texas.Counties.
Approximately 95% of the crude oil and condensate production is transported by pipeline with connections to multiple sales points.  The ability to transport more barrels by pipeline enables us to improve/optimize price realizations, reduce costs, improve reliability and lessen our environmental footprint.
Bakken – We hold approximately 270,000 net acreshave been operating in North Dakota and eastern Montana since 2006. The majority of our acreage is in core prospects within McKenzie, Mountrail, and Dunn Counties in North Dakota. We continue focusing on the high-return Myrmidon area building on the successes from our enhanced completion designs, as well as delineating our position in Hector.
Oklahoma – Our primary focus in Oklahoma has been delineation and leasehold protection in the Meramec play in the STACK and delineation of the Woodford and Springer plays in the SCOOP, as we move toward infill development. We hold net acreage with rights to the Woodford, Springer, Meramec, Osage, Oswego, Granite Wash and other Pennsylvanian and Mississippian plays, with a majority of this in the SCOOP and STACK.
Northern Delaware – We closed on multiple Permian acquisitions during 2017, with a majority of the acreage in Northern Delaware. These acquisitions give us a strong foundational footprint in the region where we have been operating since 2006. Our large scale water gathering system is handling nearly 70% of our produced water.  We are currently transporting about 75% of our oil production on pipeline.  In an effortbegun developing the Wolfcamp and Bone Spring plays. See Item 8. Financial Statements and Supplementary Data – Note 5 to optimize price realizations, we sell our production in local North Dakota markets and to select purchasers who may elect to transport outside of the state.consolidated financial statements for further detail.
Other North AmericaUnited States
Our remaining properties in North Americathe United States primarily consist of a number of outside operated assets in the Gulf of Mexico, the largest of which isincluding the Gunflint field located on Mississippi Canyon Blocks 948, 949, 992 (N/2) and 993 (N/2). The Gunflint field, in whichwhere we hold an 18% non-operated working interest, achieved first oil in the third quarter of 2016.
In 2016, we continued our progress on portfolio management, with approximately $1.3 billion of non-core assets sales, which mainly included Wyoming and West Texas properties. See Item 8. Financial Statements and Supplementary Data - Note 6 to the consolidated financial statements for information about these dispositions.interest.
International E&P Segment
We are engaged in a range of activities, including oil and gas exploration, development and production across our international locations primarily in E.G., Gabon, the Kurdistan Region of Iraq, LibyaU.K. and the U.K.Libya. We include the results of our naturalLPG processing plant, gas liquefaction operations and methanol production operations in E.G. in our International E&P segment.
AfricaInternational E&P
Equatorial GuineaProduction – We own a 63% operated working interest under a PSCproduction sharing contract in the Alba field and an 80% operated working interest in Block D, both of which isare offshore E.G. Block D was unitized with the Alba field in second quarter 2017. Operational availability from our company-operated facilities averaged approximately 97%99% in 2016.2017.
Equatorial GuineaGas Processing – We own a 52% interest in Alba Plant LLC, accounted for as an equity method investee,investment, which operates an onshore LPG processing plant located on Bioko Island. Alba field natural gas, under a long-term contract at a fixed price per btu, is processed by the LPG plant. The LPG plant extracts secondary condensate and LPG from the natural gas stream and uses some of the remaining dry natural gas in its operations.
We also own 60% of EGHoldings and 45% of AMPCO, both of which are accounted for as equity method investments. EGHoldings operates a 3.7 mmta LNG production facility and AMPCO operates a methanol plant, both located on Bioko Island. These facilities allow us to further monetize natural gas production from the Alba field. AMPCO had gross sales totaling 1,100 mt in 2016. Methanol production is sold to customers in Europe and the U.S.
The LNG production facility sells LNG under a 3.4 mmta or 460 mmcfd, sales and purchase agreement. Under the agreement, which runs through 2023, the purchaser takes delivery of the LNG on Bioko Island, with pricing linked principally to the Henry Hub index. Gross sales of LNG from this production facility totaled 3.6approximately 3.95 mmta in 2016.2017. AMPCO had gross sales totaling approximately 1,100 mt in 2017. Methanol production is sold to customers in Europe and the U.S.
United Kingdom – Our operated asset in the U.K. sector of the North Sea is the Brae area complex where we have a 42% working interest in the South, Central, North and West Brae fields, a 39% working interest in the East Brae field, and a 28% working interest in the nearby Braemar field. We own non-operated working interests in the Foinaven area complex, consisting of a 28% working interest in the main Foinaven field, a 47% working interest in East Foinaven and a 20% working interest in the T35 and T25 fields.


Libya – We hold a 16% non-operated working interest in the Waha concessions, which encompass almost 13 million gross acresincludes acreage located in the Sirte Basin of eastern Libya. CivilWhile civil and political unrest has interrupted our production operations in recent years.years, our production resumed in October 2016 at our Waha concession. During December 2016, Force Majeure was lifted in September, production commenced shortly thereafter and liftings resumed from the Es Sider crude oil terminal. During 2017 sales volumes and production continued, except for a brief interruption in December. See Item 8. Financial Statements and Supplementary Data – Note 12March 2017 due to the consolidated financial statements for additional information about our Libya operations.civil unrest.
Other International
United Kingdom – Our operated asset in the U.K. sector of the North Sea is the Brae area complex where we are the operator and have a 42% working interest in the South, Central, North and West Brae fields, a 39% working interest in the East Brae field, and a 28% working interest in the nearby Braemar field.
The strategic location of the Brae platforms, along with pipeline and onshore infrastructure, has generated third-party processing and transportation business since 1986. Currently, the operators of 31 third-party fields are contracted to use the Brae system and 72 mboed are being processed or transported through the Brae infrastructure. In addition to generating processing and pipeline tariff revenue, this third-party business optimizes infrastructure usage.
The working interest owners of the Brae area producing assets collectively own a 50% non-operated interest in the SAGE pipeline system, which has a total wet natural gas capacity of 1.1 bcf per day. The SAGE terminal at St. Fergus in northeast Scotland processes natural gas from the SAGE pipeline as well as approximately 0.3 bcf per day of third-party natural gas.
We own non-operated working interests in the Foinaven area complex, consisting of a 28% working interest in the main Foinaven field, a 47% working interest in East Foinaven and a 20% working interest in the T35 and T25 fields. The export of Foinaven liquid hydrocarbons is via shuttle tanker from an FPSO to market. All natural gas sales are to the non-operated Magnus platform for use as injection gas.
Kurdistan Region of Iraq In 2016, we relinquished to the Kurdistan Regional Government our 45% operated working interest in the Harir block located northeast of Erbil. We have non-operated interests in two blocks located north-northwest of Erbil: Atrush with a 15% working interest and Sarsang with a 20% working interest.
International E&P Exploration
Equatorial Guinea – Exploration – We hold a 63%In 2016, we relinquished to the Kurdistan Regional Government our 45% operated working interest in the Deep Luba discovery on the Alba Block and an 80% operated working interest in the Corona well on Block D. We plan to develop Block D through unitization with the Alba field. Negotiations have been substantially completed and we are awaiting approval from the host government.Harir block located northeast of Erbil. 
Gabon – Exploration – We hold a 21.25% non-operated working interest in the Diaba License G4-223 and its related permit offshore Gabon, and a 100% participating interest and operatorship in the Tchicuate block where we have an exploration and production sharing agreement.
In 2015,the third quarter 2017, we entered into separate agreements to sell certain non-core properties in our East Africa exploration acreage in EthiopiaInternational E&P segment, and Kenya. Thisa portion of this transaction closed during the first4th quarter of 2016.2017. See Item 8. Financial Statements and Supplementary Data - Note 65 to the consolidated financial statements for information about these dispositions.
Oil Sands Mining Segment
We hold a 20% non-operated interest in the AOSP, an oil sands mining and upgrading joint venture located in Alberta, Canada. Other JV partners include Shell Canada Limited with a 60% ownership interest and Chevron Canada Limited with a 20% ownership interest. Shell Canada Limited operates the joint venture, which produces bitumen from oil sands deposits in the Athabasca region utilizing mining techniques and upgrades the bitumen into synthetic crude oils. The AOSP’s mining and extraction assets are located near Fort McMurray, Alberta, and include the Muskeg River and the Jackpine mines. Gross design capacity of the combined mines is 255,000 (51,000 net) barrels of bitumen per day.
As of December 31, 2016, we own or have rights to participate in developed and undeveloped surface mineable leases totaling approximately 155,000 gross (31,000 net) acres. The underlying developed leases are held for the duration of the project, with royalties payable to the province of Alberta.
Reserves
Proved reserves are required to be disclosed by continent and by country if the proved reserves related to any geographic area, on an oil equivalent barrel basis, represent 15% or more of our total proved reserves. A geographic area can be an individual country, group of countries within a continent or a continent. Other International ("Other Int’l"), includes the U.K. and the Kurdistan Region of Iraq. Approximately 79%72% of our proved reserves are located in OECD countries.

countries, with 70% located within the U.S.
The following tables set forth estimated quantities of our total proved crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves based upon an SEC pricing for period ended December 31, 2016.2017.
North America Africa      Africa    
December 31, 2016  U.S.  Canada Total   E.G.   Other Total     Other Int'l Total
December 31, 2017  U.S.  E.G.   Libya Total     Other Int'l Total from Cont Ops
Proved Developed Reserves                          
Crude oil and condensate (mmbbl)
238
 
 238
 45
 172
 217
 13
 468
263
 39
 165
 204
 17
 484
Natural gas liquids (mmbbl)
78
 
 78
 24
 
 24
 
 102
118
 25
 
 25
 
 143
Natural gas (bcf)
648
 
 648
 943
 95
 1,038
 5
 1,691
726
 833
 94
 927
 2
 1,655
Synthetic crude oil (mmbbl)

 692
 692
 
 
 
 
 692
Total proved developed reserves (mmboe)
424
 692
 1,116
 226
 188
 414
 14
 1,544
502
 203
 181
 384
 17
 903
Proved Undeveloped Reserves                     

   

Crude oil and condensate (mmbbl)
325
 
 325
 
 
 
 9
 334
307
 
 
 
 9
 316
Natural gas liquids (mmbbl)
92
 
 92
 
 
 
 
 92
111
 
 
 
 
 111
Natural gas (bcf)
640
 
 640
 
 110
 110
 5
 755
598
 
 110
 110
 6
 714
Synthetic crude oil (mmbbl)

 
 
 
 
 
 
 
Total proved undeveloped reserves (mmboe)
524
 
 524
 
 18
 18
 10
 552
518
 
 18
 18
 10
 546
Total Proved Reserves                     

   

Crude oil and condensate (mmbbl)
563
 
 563
 45
 172
 217
 22
 802
570
 39
 165
 204
 26
 800
Natural gas liquids (mmbbl)
170
 
 170
 24
 
 24
 
 194
229
 25
 
 25
 
 254
Natural gas (bcf)
1,288
 
 1,288
 943
 205
 1,148
 10
 2,446
1,324
 833
 204
 1,037
 8
 2,369
Synthetic crude oil (mmbbl)

 692
 692
 
 
 
 
 692
Total proved reserves (mmboe)
948
 692
 1,640
 226
 206
 432
 24
 2,096
1,020
 203
 199
 402
 27
 1,449
Of the total estimated proved reserves, approximately 55% was crude oil and condensate. As of December 31, 2016, we had total estimated proved reserves of 802 mmbbl of crude oil and condensate, 194 mmbbl of NGLs, 2,446 bcf of natural gas, and 692 mmbbl of synthetic crude oil. Combined, total estimated proved reserves are 2,096 mmboe, of which liquids represents 81 percent. As of December 31, 2016, we had2017, our estimated proved developed reserves totaled 1,544903 mmboe or 74%62% and estimated proved undeveloped reserves totaling 552546 mmboe or 26%38% of our total proved reserves. For additional detail on reserves, see Item 8. Financial Statements and Supplementary Data - Supplementary Information on Oil and gas Producing Activities.
Preparation of Reserve Estimates
All estimates of reserves are made in compliance with SEC Rule 4-10 of Regulation S-X. Crude oil and condensate, NGLs, natural gas and synthetic crude oil reserve estimates are reviewed and approved by our Corporate Reserves Group ("CRG"), which includes our Director of Corporate Reserves and his staff of Reserve Coordinators. Crude oil and condensate, NGLs, natural gas and synthetic crude oil reserve estimates are developed or reviewed by Qualified Reserves Estimators ("QREs"). QREs are petro-technical professionals located throughout our organization who meet the qualifications we have established for employees engaged in estimating reserves and resources. QREs have the education, experience, and training necessary to estimate reserves and resources in a manner consistent with all external reserve estimation regulations and internal resource estimation directives and practices. QREs generally hold at least a Bachelor of Science degree in the appropriate technical field, have a minimum of three years of industry experience with at least one year in reserve estimation and have completed our QRE training course. All reserves changes (including proved) must be approved by the CRG. Additionally, any change to proved reserve estimates in excess of 5 mmboe on a total field basis, within a single month, must be approved by the Director of Corporate Reserves.
The Director of Corporate Reserves, who reports to our Chief Financial Officer, has a Bachelor of Science degree in petroleum engineering and is a registered Professional Engineer in the State of New Mexico. In his 30 years with Marathon Oil, he has held numerous engineering and management positions, including more recently managing reservoir engineering and geoscience for our Eagle Ford development in South Texas. He is a 25 year member of the Society of Petroleum Engineers ("SPE").
Technologies used in proved reserves estimation includes statistical analysis of production performance, decline curve analysis, pressure and rate transient analysis, pressure gradient analysis, reservoir simulation and volumetric analysis. The

observed statistical nature of production performance coupled with highly certain reservoir continuity or quality within the reliable technology areas and sufficient proved developed locations establish the reasonable certainty criteria required for booking proved reserves.
Estimates of synthetic crude oil reserves were prepared by GLJ Petroleum Consultants of Calgary, Alberta, Canada, third-party consultants during 2015 and 2014. Their reports for all years are filed as exhibits to this Annual Report on Form 10-K. The individual responsible, during 2015 and 2014, for the estimates of our synthetic crude oil reserves had 15 years of experience in petroleum engineering, has conducted surface mineable oil sands evaluations since 2009 and is a registered Practicing Professional Engineer in the Province of Alberta.
Audits of Estimates
We engage third-party consultants to provide, at a minimum, independent estimates for fields that comprise 80% of our total proved reserves over a rolling four-year period. We exceeded this percentage for the four-year period ended December 31, 2016, with 84% of our total proved reserves independently audited. An audit tolerance at a field level of +/- 10%, to our internal estimates, has been established. Should the third-party consultants’ initial analysis fall outside our tolerance band, both parties will re-examine the information provided, request additional data and refine their analysis, if appropriate. In the very limited instances where differences outside the 10% tolerance cannot be resolved by year end, a plan to resolve the difference is developed and executive management consent is obtained. The audit process did not result in any significant changes to our reserve estimates for 2016, 2015 or 2014.
During 2016, 2015 and 2014, Netherland, Sewell & Associates, Inc. prepared a reserves certification for the last three reporting periods for the Alba field in E.G. The NSAI summary reports are filed as an exhibit to this Annual Report on Form 10-K. Members of the NSAI team have multiple years of industry experience, having worked for large, international oil and gas companies before joining NSAI. NSAI’s technical team members meet or exceed the education, training, and experience requirements set forth in the Standards Pertaining to the Estimating and Auditing of Oil and Gas Reserves Information promulgated by the Society of Petroleum Engineers. The senior technical advisor has over 12 years of practical experience in petroleum engineering and the estimation and evaluation of reserves and is a registered Professional Engineer in the State of Texas. The second team member has over 10 years of practical experience in petroleum geosciences and is a licensed Professional Geoscientist in the State of Texas.
Ryder Scott Company also performed audits of the prior years' reserves of several of our fields in 2016, 2015 and 2014. Their summary reports are filed as exhibits to this Annual Report on Form 10-K. The team lead for Ryder Scott has over 34 years of industry experience, having worked for a major financial advisory services group before joining Ryder Scott. He is a 25 year member of SPE and is a registered Professional Engineer in the State of Texas.


Productive and Drilling Wells
For our North AmericaUnited States E&P and International E&P segments, the following table sets forth gross and net productive wells, service wells and drilling wells as of December 31 for the years presented.
Productive Wells(a)
        Productive Wells       ��
Oil Natural Gas Service Wells   Drilling WellsOil Natural Gas Service Wells   Drilling Wells
Gross Net Gross Net Gross Net Gross NetGross Net Gross Net Gross Net Gross Net
2017               
U.S.5,132
 1,905
 1,690
 676
 799
 70
 33
 13
E.G.
 
 19
 12
 
 
 
 
Libya1,071
 175
 7
 2
 94
 16
 
 
Total Africa1,071
 175
 26
 14
 94
 16
 
 
Other International61
 22
 19
 7
 23
 8
 
 
Total6,264
 2,102
 1,735
 697
 916
 94
 33
 13
2016               
              
U.S. (b)
4,533
 1,650
 1,830
 708
 821
 85
 42
 10
U.S.(a)4,533
 1,650
 1,830
 708
 821
 85
    
E.G.
 
 17
 11
 2
 1
 
 

 
 17
 11
 2
 1
    
Other Africa1,071
 175
 7
 1
 94
 16
 
 
Libya1,071
 175
 7
 1
 94
 16
    
Total Africa1,071
 175
 24
 12
 96
 17
 
 
1,071
 175
 24
 12
 96
 17
    
Other International62
 23
 35
 14
 23
 8
 
 
62
 23
 35
 14
 23
 8
    
Total5,666
 1,848
 1,889
 734
 940
 110
 42
 10
5,666
 1,848
 1,889
 734
 940
 110
    
2015
                             
U.S.(a)7,198
 2,878
 1,796
 750
 2,727
 747
    
U.S.7,198
 2,878
 1,796
 750
 2,727
 747
    
E.G.
 
 17
 11
 2
 1
    
 
 17
 11
 2
 1
    
Other Africa1,071
 175
 7
 1
 94
 16
    
Libya1,071
 175
 7
 1
 94
 16
    
Total Africa1,071
 175
 24
 12
 96
 17
    1,071
 175
 24
 12
 96
 17
    
Other International59
 21
 39
 16
 24
 8
    59
 21
 39
 16
 24
 8
    
Total8,328
 3,074
 1,859
 778
 2,847
 772
    8,328
 3,074
 1,859
 778
 2,847
 772
    
2014               
U.S.7,058
 2,919
 2,246
 1,023
 2,638
 760
    
E.G.
 
 16
 11
 2
 1
    
Other Africa1,071
 175
 7
 1
 94
 16
    
Total Africa1,071
 175
 23
 12
 96
 17
    
Other International55
 20
 39
 16
 24
 8
    
Total8,184
 3,114
 2,308
 1,051
 2,758
 785
    
(a)
Of the gross productive wells, wells with multiple completions operated by us totaled 8, 12 and 31 as of December 31, 2016, 2015 and 2014. Information on wells with multiple completions operated by others is unavailable to us.
(b) 
Reduction in December 31, 2016 gross and net productive wells and service wells is primarily due to the dispositions of ourcertain conventional West Texas and Wyoming assets in 2016. See Item 8. Financial Statements and Supplementary Data - Note 65 to the consolidated financial statements for information about these dispositions.




Drilling Activity
For our North AmericaUnited States E&P and International E&P segments, the table below sets forth, by geographic area, the number of net productive and dry development and exploratory wells completed as of December 31 for the years represented.
Development Exploratory  Development Exploratory  
Oil 
Natural
Gas
 Dry Total Oil 
Natural
Gas
 Dry Total TotalOil 
Natural
Gas
 Dry Total Oil 
Natural
Gas
 Dry Total Total
20172017            
U.S.107
 27
 
 134
 88
 16
 
 104
 238
E.G.
 
 
 
 
 
 
 
 
Libya
 
 
 
 
 
 
 
 
Total Africa
 
 

 
 
 
 
 
 
Other International
 
 
 
 
 
 
 
 
Total107
 27
 
 134
 88
 16
 
 104
 238
20162016            2016            
U.S.64
 12
 
 76
 70
 27
 
 97
 173
64
 12
 
 76
 70
 27
 
 97
 173
E.G.
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
Other Africa
 
 
 
 
 
 
 
 
Libya
 
 
 
 
 
 
 
 
Total Africa
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
Other International
 
 
 
 
 
 
 
 

 
 
 
 
 
 
 
 
Total64
 12
 
 76
 70
 27
 
 97
 173
64
 12
 
 76
 70
 27
 
 97
 173
20152015            2015            
U.S.135
 36
 11
 182
 49
 48
 1
 98
 280
135
 36
 11
 182
 49
 48
 1
 98
 280
E.G.
 1
 
 1
 
 
 1
 1
 2

 1
 
 1
 
 
 1
 1
 2
Other Africa
 
 
 
 
 
 
 
 
Libya
 
 
 
 
 
 
 
 
Total Africa
 1
 
 1
 
 
 1
 1
 2

 1
 
 1
 
 
 1
 1
 2
Other International1
 
 
 1
 
 
 
 
 1
1
 
 
 1
 
 
 
 
 1
Total136
 37
 11
 184
 49
 48
 2
 99
 283
136
 37
 11
 184
 49
 48
 2
 99
 283
2014            
U.S.253
 43
 1
 297
 49
 19
 4
 72
 369
E.G.
 
 
 
 
 
 1
 1
 1
Other Africa1
 
 
 1
 
 
 
 
 1
Total Africa1
 
 
 1
 
 
 1
 1
 2
Other International1
 
 
 1
 
 
 
 
 1
Total255
 43
 1
 299
 49
 19
 5
 73
 372
Acreage
We believe we have satisfactory title to our North AmericaUnited States E&P and International E&P properties in accordance with standards generally accepted in the industry; nevertheless, we can be involved in title disputes from time to time which may result in litigation. In the case of undeveloped properties, an investigation of record title is made at the time of acquisition. Drilling title opinions are usually prepared before commencement of drilling operations. Our title to properties may be subject to burdens such as royalty, overriding royalty, carried, net profits, working and other similar interests and contractual arrangements customary in the industry. In addition, our interests may be subject to obligations or duties under applicable laws or burdens such as net profits interests, liens related to operating agreements, development obligations or capital commitments under international PSCsproduction sharing contracts or exploration licenses.
The following table sets forth, by geographic area, the gross and net developed and undeveloped acreage held in our North AmericaUnited States E&P and International E&P segments as of December 31, 2016.2017.
Developed Undeveloped 
Developed and
Undeveloped
Developed Undeveloped 
Developed and
Undeveloped
(In thousands)Gross     Net Gross     Net Gross     NetGross     Net Gross     Net Gross     Net
U.S.1,399
 1,053
 413
 386
 1,812
 1,439
1,529
 1,008
 388
 322
 1,917
 1,330
Canada
 
 142
 54
 142
 54
Total North America1,399
 1,053
 555
 440
 1,954
 1,493
E.G.45
 29
 92
 73
 137
 102
82
 67
 54
 36
 136
 103
Libya12,909
 2,108
 
 
 12,909
 2,108
Other Africa12,909
 2,108
 2,519
 753
 15,428
 2,861

 
 277
 277
 277
 277
Total Africa12,954
 2,137
 2,611
 826
 15,565
 2,963
12,991
 2,175
 331
 313
 13,322
 2,488
Other International86
 31
 171
 32
 257
 63
86
 31
 171
 32
 257
 63
Total14,439
 3,221
 3,337
 1,298
 17,776
 4,519
14,606
 3,214
 890
 667
 15,496
 3,881

In the ordinary course of business, based on our evaluations of certain geologic trends and prospective economics, we have allowed certain lease acreage to expire and may allow additional acreage to expire in the future. If production is not established or we take no other action to extend the terms of the leases, licenses or concessions, additional undeveloped acreage will expire in future years. We plan to continue the terms of certain of these licenses and concession areas or retain leases through operational or administrative actions.

Net ProductionSales Volumes
North America Africa 
    
Africa 
      
  U.S.  Canada Total   E.G.   Other Total     Other Int'l Disc Ops 
Total
  U.S.  E.G.   Libya Other Int'l Cont Ops Disc Ops 
Total
Year Ended December 31,                              
20172017            
Crude and condensate (mbbld)(a)
133
 21
 19
 12
 185
 
 185
Natural gas liquids (mbbld)
43
 11
 
 1
 55
 
 55
Natural gas (mmcfd)(b)
348
 459
 4
 22
 833
 
 833
Synthetic crude oil (mbbld)(c)

 
 
 
 
 18
 18
Total sales volumes (mboed)
234
 109
 20
 16
 379
 18
 397
20162016                2016       
   
Crude and condensate (mbbld)(a)
131
 
 131
 20
 3
 23
 12
 
 166
131
 20
 3
 12
 166
 
 166
Natural gas liquids (mbbld)
40
 
 40
 11
 
 11
 
 
 51
40
 11
 
 
 51
 
 51
Natural gas (mmcfd)(b)
314
 
 314
 425
 
 425
 28
 
 767
314
 425
 
 28
 767
 
 767
Synthetic crude oil (mbbld)(c)

 48
 48
 
 
 
 
 
 48

 
 
 
 
 48
 48
Total production (mboed)
223
 48
 271
 102
 3
 105
 17
 
 393
Total sales volumes (mboed)
223
 102
 3
 17
 345
 48
 393
20152015   
     
     
2015       
   
Crude and condensate (mbbld)(a)
171
 
 171
 19
 
 19
 14
 
 204
171
 19
 
 14
 204
 
 204
Natural gas liquids (mbbld)
39
 
 39
 10
 
 10
 
 
 49
39
 10
 
 
 49
 
 49
Natural gas (mmcfd)(b)
351
 
 351
 410
 
 410
 21
 
 782
351
 410
 
 21
 782
 
 782
Synthetic crude oil (mbbld)(c)

 45
 45
 
 
 
 
 
 45

 
 
 
 
 45
 45
Total production (mboed)
269
 45
 314
 97
 
 97
 18
 
 429
2014   
     
     
Crude and condensate (mbbld)(a)
157
 
 157
 21
 7
 28
 11
 48
 244
Natural gas liquids (mbbld)
29
 
 29
 10
 
 10
 
 
 39
Natural gas (mmcfd)(b)
310
 
 310
 439
 1
 440
 21
 37
 808
Synthetic crude oil (mbbld)(c)

 41
 41
 
 
 
 
 
 41
Total production (mboed)
238
 41
 279
 104
 7
 111
 15
 54
 459
Total sales volumes (mboed)
269
 97
 
 18
 384
 45
 429
(a) 
The amounts correspond with the basis for fiscal settlements with governments, representing equity tanker liftings and direct deliveries of liquid hydrocarbons.
(b) 
Excludes volumesIncludes natural gas acquired from third parties for injection and subsequent resale.
(c) 
Upgraded bitumen excluding blendstocks.


Average Production Cost per Unit (a) 
North America Africa        Africa        
(Dollars per boe)  U.S.  Canada Total   E.G.   Other Total     Other Int'l Disc Ops 

Total
  U.S.  E.G.   Libya Other Int'l Cont Ops Disc Ops 

Total
2017$9.49
 $2.12
 $6.08
 $26.61
 $7.90
 $29.72
 $9.23
2016$9.84
 $29.36
 $13.35
 $2.17
 N.M. $2.17
 $23.13
 $
 $11.02
9.84
 2.17
 N.M.
 23.13
 8.41
 29.36
 11.02
201510.65
 38.42
 14.69
 2.37
 N.M. 2.37
 27.23
 
 12.62
10.65
 2.37
 N.M.
 27.23
 9.54
 38.42
 12.62
201413.34
 46.63
 18.73
 4.03
 N.M. 4.03
 47.06
 8.92
 15.37
(a) 
Production, severance and property taxes are excluded; however, shipping and handling as well as other operating expenses are included in the production costs used in this calculation. See Item 8. Financial Statements and Supplementary Data – Supplementary Information on Oil and Gas Producing Activities - Results of Operations for Oil and Gas Production Activities for more information regarding production costs.
N.M. Not meaningful information due to limited sales.

Average Sales Price per Unit(a) 
North America Africa 
    
 Africa 
    
(Dollars per unit)  U.S.  Canada Total   E.G.   Other Total     Other Int'l Disc Ops 
Total
  U.S.  E.G.   Libya Total     Other Int'l Disc Ops 
Total
20172017            
Crude and condensate (bbl)
$49.35
 $46.02
 $60.72
 $53.11
 $52.66
 $
 $50.38
Natural gas liquids (bbl)
20.55
 1.00
(b) 

 1.00
 39.65
 
 16.65
Natural gas (mcf)
2.84
 0.24
(b) 
5.03
 0.28
 6.28
 
 1.51
Synthetic crude oil (bbl)

 
 
 
 
 47.39
 47.39
20162016                2016            
Crude and condensate (bbl)
$38.57
 $
 $38.57
 $38.85
 $57.69
 $40.95
 $43.21
 $
 $39.23
$38.57
 $38.85
 $57.69
 $40.95
 $43.21
 $
 $39.23
Natural gas liquids (bbl)
13.15
 
 13.15
 1.00
(b) 

 1.00
 26.41
 
 10.68
13.15
 1.00
(b) 

 1.00
 26.41
 
 10.68
Natural gas (mcf)
2.38
 
 2.38
 0.24
(b) 

 0.24
 4.80
 
 1.26
2.38
 0.24
(b) 

 0.24
 4.80
 
 1.26
Synthetic crude oil (bbl)

 37.57
 37.57
 
 
 
 
 
 37.57

 
 
 
 
 37.57
 37.57
20152015                2015            
Crude and condensate (bbl)
$43.50
 $
 $43.50
 $42.83
 $
 $42.83
 $53.91
 $
 $44.14
$43.50
 $42.83
 $
 $42.83
 $53.91
 $
 $44.14
Natural gas liquids (bbl)
13.37
 
 13.37
 1.00
(b) 

 1.00
 32.53
 
 11.16
13.37
 1.00
(b) 

 1.00
 32.53
 
 11.16
Natural gas (mcf)
2.66
 
 2.66
 0.24
(b) 

 0.24
 6.85
 
 1.50
2.66
 0.24
(b) 

 0.24
 6.85
 
 1.50
Synthetic crude oil (bbl)

 40.13
 40.13
 
 
 
 
 
 40.13

 
 
 
 
 40.13
 40.13
2014                
Crude and condensate (bbl)
$85.25
 $
 $85.25
 $81.01
 $94.70
 $84.48
 $94.31
 $109.80
 $90.37
Natural gas liquids (bbl)
33.42
 
 33.42
 1.00
(b) 

 1.00
 67.73
 
 25.25
Natural gas (mcf)
4.57
 
 4.57
 0.24
(b) 
3.11
 0.25
 8.27
 9.94
 2.55
Synthetic crude oil (bbl)

 83.35
 83.35
 
 
 
 
 
 83.35
(a) 
Excludes gains or losses on commodity derivative instruments.
(b) 
Primarily represents fixed prices under long-term contracts with Alba Plant LLC, AMPCO and/or EGHoldings, which are equity method investees. We include our share of income from each of these equity method investees in our International E&P Segment.

Marketing
Our reportable operating segments include activities related to the marketing and transportation of substantially all of our crude oil and condensate, NGLs and natural gas and synthetic crude oil.gas. These activities include the transportation of production to market centers, the sale of commodities to third parties and the storage of production. We balance our various sales, storage and transportation positions in order to aggregate volumes to satisfy transportation commitments and to achieve flexibility within product types and delivery points. Such activities can include the purchase of commodities from third parties for resale.
Gross Delivery Commitments
We have committed to deliver gross quantities of crude oil and condensate, NGLs and natural gas and synthetic crude oil to customers under a variety of contracts. As of December 31, 2016,2017, the contracts for fixed and determinable quantities were at variable, market-based pricing and related primarily to the following sales commitments:
 2017 2018 2019 Thereafter Commitment Period Through 2018 2019 2020 Thereafter Commitment Period Through
Eagle Ford              
Crude and condensate (mbbld)
 105
 80
 66
 51 2020 95
 65
 51
  2020
Natural gas liquids (mbbld)
 1
 1
 
  2020
Natural gas (mmcfd)
 210
 168
 168
 46 - 168 2022 168
 168
 168
 46 - 70 2022
Bakken              
Crude and condensate (mbbld)
 5
 10
 10
 5-10 2027 10
 10
 10
 5 - 10 2027
OSM       
Synthetic crude oil (mbbld)
 10
 
 
  
Natural gas (mmcfd)
 2
 2
 2
 2 - 25 2027
Oklahoma
       
Natural gas (mmcfd)

 
 90
 118
 110 - 148 2030
All of these contracts provide the options of delivering third-party volumes or paying a monetary shortfall penalty if production is inadequate. Certain volumetric requirements can also be met through purchases of third-party volumes. In addition to the sales contracts discussed above, we have entered into numerous agreements for transportation and processing of our equity production. Some of these contracts have volumetric requirements which could require monetary shortfall penalties if our production is inadequate to meet the terms.

Competition
Competition exists in all sectors of the oil and gas industry and in particular, in the exploration for and development of new reserves. Wewe compete with major integrated and independent oil and gas companies, as well as national oil companies,companies. We compete, in particular, in the exploration for theand development of new reserves, acquisition of oil and natural gas leases and other properties, the marketing and delivery of our production into worldwide commodity markets and for the labor and equipment required for exploration and development of those properties. Principal methods of competing include geological, geophysical, and engineering research and technology, experience and expertise, economic analysis in connection with portfolio management, and safely operating oil and gas producing properties. See Item 1A. Risk Factors for discussion of specific areas in which we compete and related risks.
We also compete with other producers of synthetic crude oil for the sale of our synthetic crude oil to refineries primarily in North America. Because not all refineries are able to process or refine synthetic crude oil in significant volumes, sufficient market demand may not exist at all times to absorb our share of the synthetic crude oil production from the AOSP at economically viable prices.
Environmental, Health and Safety Matters
The Health, Environmental, Safety and Corporate Responsibility Committee of our Board of Directors is responsible for overseeing our position on public issues, including environmental, health and safety matters. Our Corporate Health, Environment, Safety and Security organization has the responsibility to ensure that our operating organizations maintain environmental compliance systems that support and foster our compliance with applicable laws and regulations. Committees comprised of certain of our officers review our overall performance associated with various environmental compliance programs. We also have a Corporate Emergency Response Team which oversees our response to any major environmental or other emergency incident involving us or any of our properties.
Our businesses are subject to numerous laws and regulations relating to the protection of the environment, health and safety at the national, state and local levels. These laws and their implementing regulations and other similar state and local laws and rules can impose certain operational controls for minimization of pollution or recordkeeping, monitoring and reporting requirements or other operational or siting constraints on our business, result in costs to remediate releases of regulated substances, including crude oil, into the environment, or require costs to remediate sites to which we sent regulated substances for disposal. In some cases, these laws can impose strict liability for the entire cost of clean-up on any responsible party without regard to negligence or fault and impose liability on us for the conduct of others (such as prior owners or operators of our assets) or conditions others have caused, or for our acts that complied with all applicable requirements when we performed them. We have incurred and will continue to incur capital, operating and maintenance, and remediation expenditures as a result of environmental laws and regulations.
New laws have been enacted and regulations are being adopted by various regulatory agencies on a continuing basis and the costs of compliance with these new laws and regulations can only be broadly appraised until their implementation becomes more defined.
For a discussion of environmental capital expenditures and costs of compliance for air, water, solid waste and remediation, see Item 3. Legal Proceedings and Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Management’s Discussion and Analysis of Environmental Matters, Litigation and Contingencies.
Air and Climate Change
Environmental advocacy groups and regulatory agencies in the United States and other countries have focused considerable attention on the emissions of carbon dioxide, methane and other greenhouse gases and their potential role in climate change. Developments in greenhouse gas initiatives may affect us and other similarly situated companies operating in the oil and gas industry. As part of our commitment to environmental stewardship, we estimate and publicly report greenhouse gas emissions from our operations. We are working to continuously improve the accuracy and completeness of these estimates. In addition, we continuously strive to improve operational and energy efficiencies through resource and energy conservation where practicable and cost effective.
Government entities have filed lawsuits in California and New York seeking to hold a wide variety of companies that produce fossil fuels liable for the alleged impacts of the greenhouse gas emissions attributable to those fuels. The lawsuits allege damages as a result of global warming and the plaintiffs are seeking unspecified damages and abatement under various tort theories. Marathon Oil has been named as a defendant in six of these lawsuits in California, along with numerous other companies. Similar lawsuits may be filed in other jurisdictions. While the ultimate outcome and impact to us cannot be predicted with certainty, we believe that the claims made against us are without merit and will not have a material adverse effect on our consolidated financial position, results of operations or cash flow.
The EPA finalized a more stringent National Ambient Air Quality Standard ("NAAQS") for ozone in October 2015. This more stringent ozone NAAQS could result in additional areas being designated as non-attainment, including areas in which we operate, which may result in an increase in costs for emission controls and requirements for additional monitoring and testing, as well as a more cumbersome permitting process. The EPA anticipates promulgating final area designations under the new standard in the first half of 2018. Although there may be an adverse financial impact (including compliance costs, potential permitting delays and increased regulatory requirements) associated with this revised regulation, the extent and magnitude of

that impact cannot be reliably or accurately estimated due to the present uncertainty regarding any additional measures and how they will be implemented. The EPA's final rule has been judicially challenged by both industry and other interested parties, and the outcome of this litigation may also impact implementation and revisions to the rule.
In June 2016, the EPA published a suite of final rules specifically targeting methane emissions from the oil and gas industry, aggregation of air emissions sources and minor source permitting for operations on tribal lands. The EPA has also announced that it intends to impose methane emission standards for existing sources and has issued information collection requests for oil and natural gas facilities. We are currently evaluating the impact of these rules on our operations. If we are unable to comply with the terms of these regulations, we could be required to forego construction or implement modifications to certain operations. These regulations may also increase compliance costs for some facilities we own or operate, and result in administrative, civil and/or criminal penalties for non-compliance.

In 2010, the EPA promulgated rules that require us to monitor and submit an annual report on our greenhouse gas emissions. In October 2015, the EPA finalized rules that added new sources to the scope of the greenhouse gas monitoring and reporting requirements. These new sources include gathering and boosting facilities as well as completions and workovers from hydraulically fractured oil wells. The revisions also include the addition of well identification reporting requirements for certain facilities. Further, state, national and international requirements to reduce greenhouse emissions are being proposed and in some cases promulgated (see discussion above regarding regulation of methane emissions from the oil and gas industry by the EPA). Potential legislation and regulations pertaining to climate change could also affect our operations. The cost to comply with these laws and regulations cannot be estimated at this time.
In November 2016, the Bureau of Land Management (“BLM”) issued a final rule to further restrict venting and/or flaring of gas from facilities subject to BLM jurisdiction, and to modify certain royalty requirements.  These regulations are currently subject toBLM issued a challenge under the Congressional Review Act, which if successful, would result in complete withdrawaltwo-year stay of these requirements.requirements in December 2017 and has indicated that the requirements could be rescinded or significantly revised in the future. If not withdrawn or significantly revised, this rule is expected to result in additional costs of compliance as well as increased monitoring, recordkeeping and recording for some of our facilities.  If we are unable to comply with the terms of these regulations, we could be required to forego certain operations. These regulations may also result in administrative, civil and/or criminal penalties for non-compliance.
For additional information, see Item 1A. Risk Factors. As part of our commitment to environmental stewardship, we estimate and publicly report greenhouse gas emissions from our operations. We are working to continuously improve the accuracy and completeness of these estimates. In addition, we continuously strive to improve operational and energy efficiencies through resource and energy conservation where practicable and cost effective.
Hydraulic Fracturing
Hydraulic fracturing is a commonly used process that involves injecting water, sand and small volumes of chemicals into the wellbore to fracture the hydrocarbon-bearing rock thousands of feet below the surface to facilitate higher flow of hydrocarbons into the wellbore. Our business uses this technique extensively throughout our operations. Hydraulic fracturing has been regulated at the state and local level through permitting and compliance requirements. Federal, state and local-level laws or regulations targeting various aspects of the hydraulic fracturing process are being considered, or have been proposed or implemented. For example, the U.S. Congress has considered legislation that would require additional regulation affecting the hydraulic fracturing process, and may be expected to do so in future legislative sessions. Further, variousVarious state and local-level initiatives in regions with substantial shale resources have been or may be proposed or implemented to further regulate hydraulic fracturing practices, limit water withdrawals and water use, require disclosure of fracturing fluid constituents, restrict which additives may be used, or implement temporary or permanent bans on hydraulic fracturing.
For additional information, see Item 1A. Risk Factors.
Transportation
A number of state and federal rules apply to the transportation of liquid hydrocarbons. In 2015, the U.S. Department of Transportation (“DOT”) finalized a rule relating to testing and classification of liquid hydrocarbons and imposing additional restrictions on the types of rail cars that may be used in certain types of liquid hydrocarbon service. Similarly, in August 2016, the Pipeline and Hazardous Materials Safety Administration (“PHMSA”), a sub-agency of DOT, published a final rule setting additional safety requirements and retrofits for rail cars. PHMSA is also considering revising its regulations to require particular methods for conducting vapor pressure testing and sampling of unrefined petroleum-based products for transportation. Although our businesses do not own rail cars and purchasers of our liquid hydrocarbons make arrangements for its transportation, such regulations could increase transportation costs which are passed on to Marathon Oil by liquid hydrocarbon purchasers. In addition, PHMSA has proposed or announced the intention to propose various rules related to pipeline transportation of natural gas and/or liquid hydrocarbons. For example, in October 2015, PHMSA published a notice of proposed rulemaking amending its hazardous liquid pipeline safety regulations and in April 2016, published a notice of proposed rulemaking addressing natural gas transmission and gathering lines. Such regulations could increase the regulatory burden on our businesses where we own or operate pipelines or could otherwise increase costs to third parties that are passed on to Marathon Oil.
Water
In 2014, the EPA and the U.S. Army Corps of Engineers published proposed regulations which expand the surface waters that are regulated under the Clean Water Act ("CWA") and its various programs. While these regulations were finalized largely as proposed in 2015, the rule has been stayed by the courts pending a substantive decision on the merits. If this rule is ultimately implemented, the expansion of CWA jurisdiction will result in additional costs of compliance as well as increased monitoring, recordkeeping and recording for some of our facilities.

For additional information, see Item 1A. Risk Factors.
Concentrations of Credit Risk
We are exposed to credit risk in the event of nonpayment by counterparties, a significant portion of which are concentrated in energy-related industries. The creditworthiness of customers and other counterparties is subject to continuing review, including the use of master netting agreements, where appropriate. In 2016,2017, sales to Irving Oil and Valero Marketing and SupplyVitol and each of their respective affiliates accounted for approximately 17% and 10% of our total revenues. In 2015,2016, sales to Irving OilValero Marketing and Shell OilSupply, Tesoro Petroleum, and Flint Hills Resources and each of their respective affiliates accounted for approximately 13%, 11% and 11%10% of our total revenues. In 2014,2015, sales to Shell Oil and its affiliates accounted for approximately 10% of our total revenues.
Trademarks, Patents and Licenses
We currently hold a number of U.S. and foreign patents and have various pending patent applications.patents. Although in the aggregate our trademarks, patents and licenses are important to us, we do not regard any single trademark, patent, license or group of related trademarks, patents or licenses as critical or essential to our business as a whole.
Employees
We had 2,117approximately 2,300 active, full-time employees as of December 31, 2016.2017.

Executive Officers of the Registrant
The executive officers of Marathon Oil and their ages as of February 1, 2017,2018, are as follows:
Lee M. Tillman 5556 President and Chief Executive Officer
Sylvia J. KerriganDane E. Whitehead 5156 Executive Vice President and Chief Financial Officer
T. Mitch Little54Executive Vice President—Operations
Reginald D. Hedgebeth50Senior Vice President, General Counsel and Secretary
T. Mitch LittlePatrick J. Wagner 53 Executive Vice President—Operations
Patrick J. Wagner52Interim Chief Financial Officer and Vice President-Corporate Development and Strategy
Catherine L. Krajicek 5556 Vice President—Conventional
Gary E. Wilson 5556 Vice President, Controller and Chief Accounting Officer
Mr. Tillman was appointed president and chief executive officer in August 2013.  Mr. Tillman is also a member of our Board of Directors.  Prior to this appointment, Mr. Tillman served as vice president of engineering for ExxonMobil Development Company (a project design and execution company), where he was responsible for all global engineering staff engaged in major project concept selection, front-end design and engineering.  Between 2007 and 2010, Mr. Tillman served as North Sea production manager and lead country manager for subsidiaries of ExxonMobil in Stavanger, Norway.  Mr. Tillman began his career in the oil and gas industry at Exxon Corporation in 1989 as a research engineer and has extensive operations management and leadership experience.
Ms. KerriganMr. Whitehead was appointed executive vice president general counsel and secretarychief financial officer in October 2012, havingMarch 2017. Prior to this appointment, Mr. Whitehead served as executive vice president general counsel and secretarychief financial officer of both EP Energy Corp. and EP Energy LLC (oil and natural gas producer) since November 2009.  Prior to these appointments, Ms. KerriganMay 2012. Between 2009 and 2012 Mr. Whitehead served as assistant general counsel since January 2003.senior vice president of strategy and enterprise business development and a member of El Paso Corporation's executive committee. He joined El Paso Exploration & Production Company as senior vice president and chief financial officer in 2006. Before joining El Paso Mr. Whitehead was vice president, controller and chief accounting officer of Burlington Resources Inc. (oil and natural gas producer), and formerly senior vice president and CFO of Burlington Resources Canada.
Mr. Little was appointed executive vice president of operations in August 2016 after having served as vice president, conventional since December 2015, vice president international and offshore exploration and production operations since September 2013, and as vice president, international production operations since September 2012. Prior to that, Mr. Little was resident manager of our Norway operations and served as general manager, worldwide drilling and completions. Mr. Little joined Marathon Oil in 1986 and has since held a number of engineering and management positions of increasing responsibility.
Mr. Hedgebeth was appointed senior vice president, general counsel and secretary in April 2017. Between 2009 and 2017 Mr. Hedgebeth served as general counsel, corporate secretary and chief compliance officer for Spectra Energy Corp (oil and natural gas pipeline company) and general counsel for Spectra Energy Partners, LP. Before joining Spectra Energy Mr. Hedgebeth served as senior vice president, general counsel and secretary with Circuit City Stores, Inc. (consumer electronics company), and vice president of legal for The Home Depot, Inc. (home improvement supplies retailing company).
Mr. Wagner was appointed executive vice president—president of corporate development and strategy in April 2014,November 2017 after having served as senior vice president of corporate development and strategy since March 2017, vice president of corporate development and interim chief financial officer since August 2016 has been serving as interim chief financial officer.and vice president of corporate development since April 2014. Prior to joining Marathon Oil,this appointment, he served as senior vice president, western business unit, for QR Energy LP (an oil and natural gas producer) and the affiliated Quantum Resources Management, which he joined in early 2012 as vice president, exploitation. Prior to that, Mr. Wagner was managing director in Houston for Scotia Waterous, the oil and gas arm of Scotiabank (an international banking services provider), from 2010 to 2012. Before joining Scotia, Mr. Wagner was vice president, Gulf of Mexico, for Devon Energy Corp. (an oil and natural gas producer), having joined Devon in 2003 as manager, international exploitation.
Ms. Krajicek was appointed vice president—conventional assets in August 2016 after having served as vice president of technology and innovation since December 2015. Prior to that, Ms. Krajicek served as vice president, health, environment, safety and security from January 2015 through December 2015. In January 2018 Ms. Krajicek announced her plans to retire effective April 1, 2018. Ms. Krajicek joined Marathon Oil in 2007 and has since held a number of positions of increasing responsibility. Prior to joining the Company, Ms. Krajicek spent 22 years with Conoco and then ConocoPhillips (a multinational energy corporation), where she held a variety of reservoir engineering and asset management and development management positions for upstream and mid-stream businesses under development, both in the U.S. and internationally.
Mr. Wilson was appointed vice president, controller and chief accounting officer in October 2014. Prior to joining Marathon Oil, he served in various finance and accounting positions of increasing responsibility at Noble Energy, Inc. (a global

exploration and production company) since 2001, including as director corporate accounting from February 2014 through September 2014, director global operations services finance from October 2012 through February 2014, director controls and

reporting from April 2011 through September 2012, and international finance manager from September 2009 through March 2011.
Available Information
Our website is www.marathonoil.com. Our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K and other reports and filings with the SEC are available free of charge on our website as soon as reasonably practicable after the reports are filed or furnished with the SEC. Information contained on our website is not incorporated into this Annual Report on Form 10-K or our other securities filings. Our filings are also available in hard copy, free of charge, by contacting our Investor Relations office.
The public may read and copy any materials we file with the SEC at its Public Reference Room at 100 F Street, NE, Washington, DC 20549. Information on the operation of the Public Reference Room may be obtained by calling the SEC at 1-800-SEC-0330. The SEC also maintains a website (www.sec.gov) that contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC.
Additionally, we make available free of charge on our website:
our Code of Business Conduct and Code of Ethics for Senior Financial Officers;
our Corporate Governance Principles; and
the charters of our Audit and Finance Committee, Compensation Committee, Corporate Governance and Nominating Committee and Health, Environmental, Safety and Corporate Responsibility Committee.

Item 1A. Risk Factors
We are subject to various risks and uncertainties in the course of our business. The following summarizes significant risks and uncertainties that may adversely affect our business, financial condition or results of operations. When considering an investment in our securities, you should carefully consider the risk factors included below as well as those matters referenced in the foregoing pages under "Disclosures Regarding Forward-Looking Statements" and other information included and incorporated by reference into this Annual Report on Form 10-K.
TheA substantial decline in crude oil and condensate, NGLs and natural gas and synthetic crude oil prices since 2014 has reducedwould reduce our operating results and cash flows and regardless of the recent increase in prices, could still adversely impact our future rate of growth and the carrying value of our assets.
PricesThe markets for crude oil and condensate, NGLs and natural gas have been volatile and synthetic crude oilare likely to continue to be volatile in the future, causing prices to fluctuate widely. Our revenues, operating results and future rate of growth are highly dependent on the prices we receive for our crude oil and condensate, NGLs natural gas and synthetic crude oil. Historically, the markets for crude oil and condensate, NGLs, natural gas and synthetic crude oil have been volatile and may continue to be volatile in the future. Although, prices for WTI and Brent crude oil, Henry Hub natural gas and natural gas liquids have increased in the last several months, prices are still significantly below their highs from 2014.gas. Many of the factors influencing prices of crude oil and condensate, NGLs and natural gas and synthetic crude oil are beyond our control. These factors include:
worldwide and domestic supplies of and demand for crude oil and condensate, NGLs and natural gas and synthetic crude oil;gas;
the cost of exploring for, developing and producing crude oil and condensate, NGLs and natural gas and synthetic crude oil;gas;
the ability of the members of OPEC and certain non-OPEC members, such as Russia, to agree to and maintain production controls;
the production levels of non-OPEC countries, including production levels in the shale plays in the United States;
the level of drilling, completion and production activities by other exploration and production companies, and variability therein, in response to market conditions;
political instability or armed conflict in oil and natural gas producing regions;
changes in weather patterns and climate;
natural disasters such as hurricanes and tornadoes;
the price and availability of alternative and competing forms of energy;
the effect of conservation efforts;
epidemics or pandemics;
technological advances affecting energy consumption and energy supply;
domestic and foreign governmental regulations and taxes; and
general economic conditions worldwide.
The long-term effects of these and other factors on the prices of crude oil and condensate, NGLs and natural gas and synthetic crude oil are uncertain. Historical declines in commodity prices have adversely affected our business by:
reducing the amount of crude oil and condensate, NGLs and natural gas and synthetic crude oil that we can produce economically;
reducing our revenues, operating income and cash flows;
causing us to reduce our capital expenditures, and delay or postpone some of our capital projects;
requiring us to impair the carrying value of our assets;
reducing the standardized measure of discounted future net cash flows relating to crude oil and condensate, NGLs and natural gas and synthetic crude oil;gas; and
increasing the costs of obtaining capital, such as equity and short- and long-term debt.
Future decreases in prices could have similar adverse effects on our business.

If crude oil and condensate, NGLs, natural gas and synthetic crude oil prices remain substantially below their 2014 highs or fall below current levels, it could adversely affect the abilities of our counterparties to perform their obligations to us, including abandonment obligations, which could negatively impact our financial results.
We often enter into arrangements to conduct certain business operations, such as oil and gas exploration and production, oil sands mining or transportation of crude oil and condensate, NGLs, natural gas and synthetic crude oil, with partners and other counterparties in order to share risks associated with those operations. In addition, we market our products to a variety of purchasers. If commodity prices remain at or fall below current levels, some of our counterparties may experience liquidity problems and may not be able to meet their financial and other obligations, including abandonment obligations, to us. The inability of our joint venture partners to fund their portion of the costs under our joint venture agreements, or the nonperformance by purchasers, contractors or other counterparties of their obligations to us, could negatively impact our operating results and cash flows.
Estimates of crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves depend on many factors and assumptions, including various assumptions that are based on conditions in existence as of the dates of the estimates. Any material changes in those conditions or other factors affecting those assumptions could impair the quantity and value of our reserves.
The proved reserve information included in this Annual Report on Form 10-K has been derived from engineering and geoscience estimates. Estimates of crude oil and condensate, NGLs, natural gas and our historical synthetic crude oil reserves were prepared, in accordance with SEC regulations, by our in-house teams of reservoir engineers and geoscience professionals and were reviewed and approved by our Corporate Reserves Group.Group and third-party consultants. Prior to 2016, the synthetic

crude oil reserves estimates, included in discontinued operations, were prepared by GLJ, a third-party consulting firm experienced in working with oil sands. Reserves were valued based on SEC pricing for the periods ended December 31, 2017, 2016 2015 and 2014,2015, as well as other conditions in existence at those dates. The table below provides the 20162017 SEC pricing for certain benchmark prices:
SEC Pricing 2016SEC Pricing 2017
WTI Crude oil (per bbl)
$42.75
$51.34
Henry Hub natural gas (per mmbtu)
$2.49
$2.98
Brent crude oil (per bbl)
$43.53
$54.39
Mont Belvieu NGLs (per bbl)
$15.89
$22.03
If commodity prices were to significantly dropdecrease by approximately 10% below average prices used to estimate 20162017 proved reserves (see table above), we would not expect price related reserve revisions that couldto have a material impact on proved reserve volumes and the present value of our proved reserves. In this scenario, our OSM proved reserves represent the largest risk to be reclassified to non-proved reserves or resource category.volumes. Future reserve revisions could also result from changes in capital funding, drilling plans and governmental regulation, among other things.
Reserve estimation is a subjective process that involves estimating volumes to be recovered from underground accumulations of crude oil and condensate, NGLs and natural gas and bitumen that cannot be directly measured (bitumen is mined and then upgraded into synthetic crude oil.)measured. Estimates of economically producible reserves and of future net cash flows depend on a number of variable factors and assumptions, including:
location, size and shape of the accumulation as well as fluid, rock and producing characteristics of the accumulation;
historical production from the area, compared with production from other analogous producing areas;
volumes of bitumen in-place and various factors affecting the recoverability of bitumen and its conversion into synthetic crude oil such as historical upgrader performance;
the assumed impacts of regulation by governmental agencies;
assumptions concerning future operating costs, taxes, development costs and workover and repair costs; and
industry economic conditions, levels of cash flows from operations and other operating considerations.
As a result, different petroleum engineers and geoscientists, each using industry-accepted geologic and engineering practices and scientific methods, may produce different estimates of proved reserves and future net cash flows based on the same available data. Because of the subjective nature of such reserve estimates, each of the following items may differ materially from the estimated amounts:
the amount and timing of production;

the revenues and costs associated with that production; and
the amount and timing of future development expenditures.
If we are unsuccessful in acquiring or finding additional reserves, our future crude oil and condensate, NGLs and natural gas and synthetic crude oil production would decline, thereby reducing our cash flows and results of operations and impairing our financial condition.
The rate of production from crude oil and condensate, NGLs and natural gas and synthetic crude oil properties generally declines as reserves are depleted. Except to the extent we acquire interests in additional properties containing proved reserves, conduct successful exploration and development activities or, through engineering studies, optimize production performance or identify additional reservoirs not currently producing or secondary recovery reserves, our proved reserves will decline materially as crude oil and condensate, NGLs and natural gas and synthetic crude oil are produced. Accordingly, to the extent we are not successful in replacing the crude oil and condensate, NGLs and natural gas and synthetic crude oil we produce, our future revenues will decline. Creating and maintaining an inventory of prospects for future production depends on many factors, including:
obtaining rights to explore for, develop and produce crude oil and condensate, NGLs and natural gas and synthetic crude oil in promising areas;
drilling success;
the ability to complete long lead-time, capital-intensive projects timely and cost effectively;
the ability to find or acquire additional proved reserves at acceptable costs; and
the ability to fund such activity.

Future exploration and drilling results are uncertain and involve substantial costs.
Drilling for crude oil and condensate, NGLs and natural gas involves numerous risks, including the risk that we may not encounter commercially productive reservoirs. The costs of drilling, completing and operating wells are often uncertain, and drilling operations may be curtailed, delayed or canceled as a result of a variety of factors, including:
unexpected drilling conditions;
title problems;
pressure or irregularities in formations;
equipment failures or accidents;
inflation in exploration and drilling costs;
fires, explosions, blowouts or surface cratering;
lack of access to pipelines or other transportation methods; and
shortages or delays in the availability of services or delivery of equipment.
If crude oil and condensate, NGLs and natural gas prices decrease, it could adversely affect the abilities of our counterparties to perform their obligations to us, including abandonment obligations, which could negatively impact our financial results.
We often enter into arrangements to conduct certain business operations, such as oil and gas exploration and production, or transportation of crude oil and condensate, NGLs and natural gas, with partners and other counterparties in order to share risks associated with those operations. In addition, we market our products to a variety of purchasers. If commodity prices decrease, some of our counterparties may experience liquidity problems and may not be able to meet their financial and other obligations, including abandonment obligations, to us. The inability of our joint venture partners to fund their portion of the costs under our joint venture agreements, or the nonperformance by purchasers, contractors or other counterparties of their obligations to us, could negatively impact our operating results and cash flows.
If we are unable to complete capital projects at their expected costs and in a timely manner, or if the market conditions assumed in our project economics deteriorate, our business, financial condition, results of operations and cash flows could be materially and adversely affected.
Delays or cost increases related to capital spending programs involving drilling and completion activities, engineering, procurement and construction of facilities (including improvements and repairs to our existing facilities) could adversely affect our ability to achieve forecasted internal rates of return and operating results. Delays in making required changes or upgrades to our facilities could subject us to fines or penalties as well as affect our ability to supply certain products we produce. Such delays or cost increases may arise as a result of unpredictable factors, many of which are beyond our control, including:
denial of or delay in receiving requisite regulatory approvals and/or permits;
unplanned increases in the cost of construction materials or labor;
disruptions in transportation of components or construction materials;
increased costs or operational delays resulting from shortages of water;
adverse weather conditions, natural disasters or other events (such as equipment malfunctions, explosions, fires or spills) affecting our facilities, or those of vendors or suppliers;

shortages of sufficiently skilled labor, or labor disagreements resulting in unplanned work stoppages;
market-related increases in a project’s debt or equity financing costs; and
nonperformance by, or disputes with, vendors, suppliers, contractors or subcontractors.
Any one or more of these factors could have a significant impact on our capital projects.
Our offshore operations involve special risks that could negatively impact us.
Offshore exploration and development operations present technological challenges and operating risks because of the marine environment.  Activities in deepwater areas may pose incrementally greater risks because of water depths that limit intervention capability and the physical distance to oilfield service infrastructure and service providers.  Environmental remediation and other costs resulting from spills or releases may result in substantial liabilities.

We may incur substantial capital expenditures and operating costs as a result of compliance with and/orand changes in environmental, health, safety and security laws and regulations, and, as a result, our business, financial condition, results of operations and cash flows could be materially and adversely affected.
Our businesses are subject to numerous laws, regulations and other requirements relating to the protection of the environment, including those relating to the discharge of materials into the environment such as the venting or flaring of natural gas, waste management, pollution prevention, greenhouse gas emissions and the protection of endangered species as well as laws, regulations, and other requirements relating to public and employee safety and health and to facility security. We have incurred and may continue to incur capital, operating and maintenance, and remediation expenditures as a result of these laws, regulations, and other requirements. To the extent these expenditures, as with all costs, are not ultimately reflected in the prices of our products, our operating results will be adversely affected. The specific impact of these laws, regulations, and other requirements may vary depending on a number of factors, including the age and location of operating facilities and production processes. We may also be required to make material expenditures to modify operations, install pollution control equipment, perform site clean-ups or curtail operations that could materially and adversely affect our business, financial condition, results of operations and cash flows. We may become subject to liabilities that we currently do not anticipate in connection with new, amended or more stringent requirements, stricter interpretations of existing requirements or the future discovery of contamination. In addition, any failure by us to comply with existing or future laws, regulations, and other requirements could result in civil penalties or criminal fines and other enforcement actions against us.
We believe it is likely that the scientific and political attention to issues concerning the extent, causes of and responsibility for climate change will continue, with the potential for further regulations that could affect our operations. Our operations result in greenhouse gas emissions. Currently, various legislative or regulatory measures to address greenhouse gas emissions (including carbon dioxide, methane and nitrous oxides) are in various phases of review, discussion or implementation in countries where we operate, including the U.S., Canada, and the European Union. Internationally, the United Nations Framework Convention on Climate Change finalized an agreement among 195 nations at the 21st Conference of the Parties in Paris with an overarching goal of preventing global temperatures from rising more than 2 degrees Celsius. The agreement includes provisions that every country take some action to lower emissions, but there is no legal requirement for how or by what amount emissions should be lowered. The EPA has also finalized regulations targeting new sources of methane emissions from the oil and gas industry, and has issued requests for information on existing sources.industry. Finalization of new legislation, regulations or international agreements in the future could result in increased costs to operate and maintain our facilities, capital expenditures to install new emission controls at our facilities, and costs to administer and manage any potential greenhouse gas emissions or carbon trading or tax programs. These costs and capital expenditures could be material. Although uncertain, these developments could increase our costs, reduce the demand for crude oil and condensate, NGLs and natural gas, and synthetic crude oil, and create delays in our obtaining air pollution permits for new or modified facilities.
The potential adoption of federal, state and local legislative and regulatory initiatives related to hydraulic fracturing could result in increased compliance costs, operating restrictions or delays in the completion of oil and gas wells. 
Hydraulic fracturing is a commonly used process that involves injecting water, sand, and small volumes of chemicals into the wellbore to fracture the hydrocarbon-bearing rock thousands of feet below the surface to facilitate higher flow of hydrocarbons into the wellbore. Our business uses this technique extensively throughout our U.S. operations. Hydraulic fracturing has been regulated at the state and local level through permitting and compliance requirements. Federal, state and local-level laws or regulations targeting various aspects of the hydraulic fracturing process are being considered, or have been proposed or implemented. For example, the U.S. Congress has considered legislation that would require additional regulation affecting the hydraulic fracturing process, and may be expected to do so in future legislative sessions. Further, variousVarious state and local-level initiatives in regions with substantial shale resources have been or may be proposed or implemented to further regulate hydraulic fracturing practices, limit water withdrawals and water use, require disclosure of fracturing fluid constituents, restrict which additives may be used, or implement temporary or permanent bans on hydraulic fracturing. In 2015

the Bureau of Land ManagementBLM issued a rule governing certain hydraulic fracturing practices on lands within their jurisdiction. Whilejurisdiction; however, this rule has been stayed nationwide by court ruling, further findings by the court could resultwas rescinded in additional changes to this new rule.December 2017.
Increased regulation and attention given to the hydraulic fracturing process could lead to greater opposition, including litigation, to oil and gas activities using hydraulic fracturing techniques. Additional legislation or regulation could also lead to operational delays or increased operating costs in the production of crude oil and condensate, NGLs and natural gas, including from the shale plays, or could make it more difficult to perform hydraulic fracturing. The adoption of any federal, state or local laws or the implementation of regulations regarding hydraulic fracturing could potentially cause a decrease in the completion of new oil and gas wells and increased compliance costs which could increase costs of our operations and cause considerable delays in acquiring regulatory approvals to drill and complete wells.

The potential adoption of federal, state and local legislative and regulatory initiatives intended to address potential induced seismic activity in the areas in which we operate could result in increased compliance costs, operating restrictions or delays in the completion of oil and gas wells. 


State and federal regulatory agencies recently have focused on a possible connection between the operation of injection wells used for oil and gas waste disposal and seismic activity.  When caused by human activity, such events are called induced seismicity. Marathon does not currently own or operate water disposal wells in the current areas of interest but does contract for services that regularly inject produced water into underground injection wells. Separate and apart from the referenced potential connection between injection wells and seismicity, concerns have been raised that hydraulic fracturing activities may be correlated to anomalous seismic events. Marathon does useuses hydraulic fracturing techniques throughout its U.S. operations.

While the scientific community and regulatory agencies at all levels are continuing to study the possible linkage between oil and gas activity and induced seismicity, some state regulatory agencies have modified their regulations or guidance to mitigate potential causes of induced seismicity. For example, Oklahoma has taken numerous regulatory actions in response to concerns related to the operation of produced water disposal wells and induced seismicity, and has issued guidelines to operators in certain areas of the State curtailing injection of produced water due to seismic concerns. Marathon does not currently own or operate injection wells or contract for such services in these areas. Further, Oklahoma recently issued guidelines to operators for management of anomalous seismicity that may be related to hydraulic fracturing activities in the SCOOP/STACK area. In addition, a number of lawsuits have been filed in Oklahoma alleging damage from seismicity relating to disposal well operations. Marathon has not been named in any of those lawsuits.

Increased seismicity in Oklahoma or other areas could result in additional regulation and restrictions on our operations and could lead to operational delays or increased operating costs.  Additional regulation and attention given to induced seismicity could also lead to greater opposition, including litigation, to oil and gas activities.
Worldwide political and economic developments and changes in law or policy could adversely affect our operations and materially reduce our profitability and cash flows.
Local political and economic factors in global markets could have a material adverse effect on us. A total of 45%38% of our crude oil and condensate, NGLs and natural gas and synthetic crude oil volumes related to continuing operations in 20162017 was derived from production outside the U.S. and 55%30% of our proved reserves of crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves as of December 31, 20162017 were located outside the U.S. All of our synthetic crude oil production and proved reserves are located in Canada. We are, therefore, subject to the political, geographic and economic risks and possible terrorist activities or other armed conflict attendant to doing business within or outside of the U.S. There are many risks associated with operations in countries such as E.G., Gabon, the Kurdistan Region of Iraq and Libya, and in global markets including:
changes in governmental policies relating to crude oil and condensate, NGLs or natural gas or synthetic crude oil and taxation;
other political, economic or diplomatic developments and international monetary fluctuations;
political and economic instability, war, acts of terrorism, armed conflict and civil disturbances;
the possibility that a government may seize our property with or without compensation, may attempt to renegotiate or revoke existing contractual arrangements or may impose additional taxes or royalty burdens; and
fluctuating currency values, hard currency shortages and currency controls.

For the past several years, there have been varying degrees of political instability and public protests, including demonstrations which have been marked by violence and numerous incidences of terrorist acts, within some countries in the Middle East including Bahrain, Egypt, Iraq, Libya, Syria, Tunisia and Yemen.Africa. Some political regimes in these countries are threatened or have changed as a result of such unrest.
If such unrest continues to spread, conflicts could result in civil wars, regional conflicts, and regime changes resulting in governments that are hostile to the U.S. These may have the following results, among others:
volatility in global crude oil prices which could negatively impact the global economy, resulting in slower economic growth rates and reduced demand for our products;
negative impact on the world crude oil supply if transportation avenues are disrupted;
security concerns leading to the prolonged evacuation of our personnel;
damage to, or the inability to access, production facilities or other operating assets; and
inability of our service and equipment providers to deliver items necessary for us to conduct our operations.
Continued hostilities in the Middle East and Africa and the occurrence or threat of future terrorist attacks, or other armed conflict, could adversely affect the economies of the U.S. and other developed countries. A lower level of economic activity could result in a decline in energy consumption, which could cause our revenues and margins to decline and limit our future growth prospects. These risks could lead to increased volatility in prices for crude oil and condensate, NGLs and natural gas and synthetic crude oil.gas. In addition, these risks could increase instability in the financial and insurance markets and make it more difficult for us to access capital and to obtain the insurance coverage that we consider adequate.

Actions of governments through tax legislation or interpretations of tax law, and other changes in law, executive order and commercial restrictions could reduce our operating profitability, both in the U.S. and abroad. The U.S. government can prevent or restrict us from doing business in foreign countries. These restrictions and those of foreign governments have in the past limited our ability to operate in, or gain access to, opportunities in various countries and will continue to do so in the future. Changes in law could also adversely affect our results, including new regulations resulting in higher costs to transport our production by pipeline, rail car, truck or vessel or the adoption of government payment transparency regulations that could require us to disclose competitively sensitive commercial information or that could cause us to violate the non-disclosure laws of other countries.
Our level of indebtedness may limit our liquidity and financial flexibility.
As of December 31, 2016,2017, our total debt was $7.3$5.5 billion, of which $686 million iswith no debt due within 12the next 24 months. Our indebtedness could have important consequences to our business, including, but not limited to, the following:
we may be more vulnerable to general adverse economic and industry conditions;
a portion of our cash flows from operating activities must be used to service our indebtedness and is not available for other purposes;
our flexibility in planning for, or reacting to, changes in our industry may be limited;
a financial covenant in our Credit Agreement stipulates that our total debt to capitalization ratio will not exceed 65% as of the last day of any fiscal quarter, and if exceeded, may make additional borrowings more expensive and affect our ability to plan for and react to changes in the economy and our industry;
we may be at a competitive disadvantage as compared to similar companies that have less debt; and
additional financing in the future for working capital, capital expenditures, acquisitions or development activities, general corporate or other purposes may have higher costs and more restrictive covenants.
We may incur additional debt in order to fund our capital expenditures, acquisitions or development activities, or for general corporate or other purposes. A higher level of indebtedness increases the risk that our financial flexibility may deteriorate. Our ability to meet our debt obligations and service our debt depends on future performance. General economic conditions, crude oil and condensate, NGLs and natural gas and synthetic crude oil prices, and financial, business and other factors will affect our operations and our future performance. Many of these factors are beyond our control and we may not be able to generate sufficient cash flow to pay the interest on our debt, and future working capital, borrowings and equity financing may not be available to pay or refinance such debt. See Item 8. Financial Statements and Supplementary Data – Note 1715 to the consolidated financial statements for a discussion of debt obligations.
A further downgrade in our credit rating could negatively impact our cost of and ability to access capital, which could adversely affect our business.

We receive debt ratings from the major credit rating agencies in the United States. Due to the decline in crude oil and U.S. natural gas prices in recent years, credit rating agencies reviewed companies in the energy industry, including us. In the first quarter of 2016,At December 31, 2017, our corporate credit rating was downgraded byratings were: Standard & Poor's Global Ratings toServices BBB- (stable) from; Fitch Ratings BBB (stable), by Fitch Ratings to BBB (negative) from BBB+ (stable); and by Moody's Investor Services, Inc. to Ba1 (negative) from Baa1 (stable). On October 11, 2016 Moody's subsequently revised their outlook of our corporate credit rating to stable from negative. The credit rating process is contingent upon a number of factors, many of which are beyond our control. A further downgrade of our credit ratings could negatively impact our cost of capital and our ability to access the capital markets, increase the interest rate and fees we pay on our revolving credit facility, and may limit or reduce credit lines with our bank counterparties. We could also be required to post letters of credit or other forms of collateral for certain contractual obligations, which could increase our costs and decrease our liquidity or letter of credit capacity under our unsecured revolving credit facility. Limitations on our ability to access capital could adversely impact the level of our capital spending program, our ability to manage our debt maturities, or our flexibility to react to changing economic and business conditions.

Our commodity price risk management activities may prevent us from fully benefiting from commodity price increases and may expose us to other risks, including counterparty risk.
Global commodity prices are volatile. In order to mitigate commodity price volatility and increase the predictability of cash flows related to the marketing of our crude oil and natural gas, we, from time to time, enter into crude oil and natural gas hedging arrangements with respect to a portion of our expected production. While hedging arrangements are intended to mitigate commodity price volatility, we may be prevented from fully realizing the benefits of price increases above the price levels of the derivative instruments used to manage price risk. In addition, our hedging arrangements may expose us to the risk of financial loss in certain circumstances, including instances in which the counterparties to our hedging contracts fail to perform under the contracts. See Item 7A. Quantitative and Qualitative Disclosures about Market Risk.
Our business could be negatively impacted by cyber-attackscyberattacks targeting our computer and telecommunications systems and infrastructure.infrastructure, or targeting those of our third-party service providers.
Our business, like other companies in the oil and gas industry, has become increasingly dependent on digital technologies.technologies, including technologies that are managed by third-party service providers on whom we rely to help us collect, host or process information. Such technologies are integrated into our business operations and used as a part of our crude oil and condensate, NGLs, natural gas and synthetic crude oil production and distribution systems in the U.S. and abroad, including those systems used to transport production to market.market, to enable communications, and to provide a host of other support services for our business. Use of the internet and other public networks for communications, services, and storage, including “cloud” computing, exposes all users (including our business) to cybersecurity risks.
While we and our third-party service providers commit resources to the design, implementation, and monitoring of our information systems, there is no guarantee that our security measures will provide absolute security. Despite these security measures, we may not be able to anticipate, detect, or prevent cyberattacks, particularly because the methodologies used by attackers change frequently or may not be recognized until launched, and because attackers are increasingly using techniques designed to circumvent controls and avoid detection. We and our third-party service providers may therefore be vulnerable to security events that are beyond our control, and we may be the target of cyber-attacks, as well as physical attacks, which could result in information security breaches and significant disruption to our business. Our information systems and related infrastructure have experienced attempted and actual minor breaches of our cybersecurity in the past, but we have not suffered any losses or breaches which had a material effect on our business, operations or reputation relating to such attacks; however, there is no assurance that we will not suffer such losses or breaches in the future. 
As cyber-attackscyberattacks continue to evolve, we may be required to expend significant additional resources to respond to cyberattacks, to continue to modify or enhance our protective measures, or to investigate and remediate any information systems and related infrastructure security vulnerabilities. We may also be subject to regulatory investigations or litigation relating from cybersecurity issues.
Our operations may be adversely affected by pipeline, rail and other transportation capacity constraints.
The marketability of our production depends in part on the availability, proximity, and capacity of pipeline facilities, rail cars, trucks and vessels. If any pipelines, rail cars, trucks or vessels become unavailable, we would, to the extent possible, be required to find a suitable alternative to transport our crude oil and condensate, NGLs and natural gas, and synthetic crude oil, which could increase the costs and/or reduce the revenues we might obtain from the sale of our production. Both the cost and availability of pipelines, rail cars, trucks, or vessels to transport our crude oil could be adversely impacted by new and expected state or federal regulations relating to transportation of crude oil.
If we acquire crude oil and natural gas properties, our failure to fully identify existing and potential problems, to accurately estimate reserves, production rates or costs, or to effectively integrate the acquired properties into our operations could materially and adversely affect our business, financial condition and results of operations.
We typically seek the acquisition of crude oil and condensate, NGLs, natural gas properties and synthetic crude oil properties.leases.  Although we perform reviews of properties to be acquired in a manner that we believe is diligent and consistent with industry practices, reviews of records and properties may not necessarily reveal existing or potential problems, nor may they permit us to become sufficiently familiar with the properties in order to fully assess possible deficiencies and potential problems.  Even when problems with a property are identified, we often assume environmental and other risks and liabilities in connection with acquired properties pursuant to the acquisition agreements.  Moreover, there are numerous uncertainties inherent in estimating quantities of crude oil and condensate, NGLs, natural gas and synthetic crude oil reserves (as previously discussed), actual future production rates and associated costs with respect to acquired properties.  Actual reserves, production rates and costs may vary substantially from those assumed in our estimates.  In addition, an acquisition may have a material and adverse effect on our business and results of operations, particularly during the periods in which the operations of the acquired

properties are being integrated into our ongoing operations or if we are unable to effectively integrate the acquired properties into our ongoing operations.

We operate in a highly competitive industry, and many of our competitors are larger and have available resources in excess of our own.
The oil and gas industry is highly competitive, and many competitors, including major integrated and independent oil and gas companies, as well as national oil companies, are larger and have substantially greater resources at their disposal than we do. We compete with these companies for the acquisition of oil and natural gas leases and other properties. We also compete with these companies for equipment and personnel, including petroleum engineers, geologists, geophysicists and other specialists, required to develop and operate those properties and in the marketing of crude oil and condensate, NGLs and natural gas and synthetic crude oil to end-users. Such competition can significantly increase costs and affect the availability of resources, which could provide our larger competitors a competitive advantage when acquiring equipment, leases and other properties. They may also be able to use their greater resources to attract and retain experienced personnel.
Many of our major projects and operations are conducted with partners, which may decrease our ability to manage risk.
We often enter into arrangements to conduct certain business operations, such as oil and gas exploration and production or oil sands mining, with partners in order to share risks associated with those operations. However, these arrangements also may decrease our ability to manage risks and costs, particularly where we are not the operator. We could have limited influence over and control of the behaviors and performance of these operations. In addition, misconduct, fraud, noncompliance with applicable laws and regulations or improper activities by or on behalf of one or more of our partners could have a significant negative impact on our business and reputation.
Our operations are subject to business interruptions and casualty losses. We do not insure against all potential losses and therefore we could be seriously harmed by unexpected liabilities and increased costs.
Our North AmericaUnited States E&P and International E&P operations are subject to unplanned occurrences, including blowouts, explosions, fires, loss of well control, spills, tornadoes, hurricanes and other adverse weather, tsunamis, earthquakes, volcanic eruptions or nuclear or other disasters, labor disputes and accidents. Our OSM operations are subject to business interruptions due to breakdown or failure of equipment or processes and unplanned events such as fires, earthquakes, explosions or other interruptions. These same risks can be applied to the third-parties which transport our products from our facilities. A prolonged disruption in the ability of any pipelines, rail cars, trucks, or vessels to transport our production could contribute to a business interruption or increase costs.
Our operations are also subject to the additional hazards of pollution, releases of toxic gas and other environmental hazards and risks. These hazards could result in serious personal injury or loss of human life, significant damage to property and equipment, environmental pollution, impairment of operations and substantial losses to us. Various hazards have adversely affected us in the past, and damages resulting from a catastrophic occurrence in the future involving us or any of our assets or operations may result in our being named as a defendant in one or more lawsuits asserting potentially large claims or in our being assessed potentially substantial fines by governmental authorities. We maintain insurance against many, but not all, potential losses or liabilities arising from operating hazards in amounts that we believe to be prudent. Uninsured losses and liabilities arising from operating hazards could reduce the funds available to us for capital, exploration and investment spending and could have a material adverse effect on our business, financial condition, results of operations and cash flows. Historically, we have maintained insurance coverage for physical damage andincluding at times resulting business interruption to our major onshore and offshore facilities, with significant self-insured retentions. In the future, we may not be able to maintain or obtain insurance of the type and amount we desire at reasonable rates. As a result of market conditions, premiums and deductibles for our insurance policies will change over time and could escalate. In some instances, certain insurance could become unavailable or available only for reduced amounts of coverage. For example, due to historical hurricane activity, the availability of insurance coverage for windstorms has changed and, in some instances, it is uneconomical. As a result, our exposure to losses from future windstorm activity has increased.
Litigation by private plaintiffs or government officials or entities could adversely affect our performance.
We currently are defending litigation and anticipate that we will be required to defend new litigation in the future. The subject matter of such litigation may include releases of hazardous substances from our facilities, privacy laws, contract disputes, royalty disputes or any other laws or regulations that apply to our operations. In some cases the plaintiff or plaintiffs seek alleged damages involving large classes of potential litigants, and may allege damages relating to extended periods of time or other alleged facts and circumstances. If we are not able to successfully defend such claims, they may result in substantial liability. We do not have insurance covering all of these potential liabilities. In addition to substantial liability, litigation may also seek injunctive relief which could have an adverse effect on our future operations.
For instance, government entities have filed lawsuits in California and New York seeking to hold a wide variety of companies that produce fossil fuels liable for the alleged impacts of the greenhouse gas emissions attributable to those fuels. The lawsuits allege damages as a result of global warming and the plaintiffs are seeking unspecified damages and abatement under various tort theories. Marathon Oil has been named as a defendant in six of these lawsuits in California, along with numerous other companies. Similar lawsuits may be filed in other jurisdictions. The ultimate outcome and impact to us cannot

be predicted with certainty, and we could incur substantial legal costs associated with defending these and similar lawsuits in the future.
In connection with our separation from MPC, MPC agreed to indemnify us for certain liabilities. However, there can be no assurance that the indemnity will be sufficient to protect us against the full amount of such liabilities, or that MPC’s ability to satisfy its indemnification obligations will not be impaired in the future.
Pursuant to the Separation and Distribution Agreement and the Tax Sharing Agreement we entered into with MPC in connection with the spin-off, MPC agreed to indemnify us for certain liabilities. However, third parties could seek to hold us responsible for any of the liabilities that MPC agreed to retain or assume, and there can be no assurance that the indemnification from MPC will be sufficient to protect us against the full amount of such liabilities, or that MPC will be able to fully satisfy its indemnification obligations. In addition, even if we ultimately succeed in recovering from MPC any amounts for which we are held liable, we may be temporarily required to bear these losses ourselves.
The spin-off could result in substantial tax liability.
We obtained a private letter ruling from the IRS substantially to the effect that the distribution of shares of MPC common stock in the spin-off qualified as tax free to MPC, us and our stockholders for U.S. federal income tax purposes under Sections 355 and 368 and related provisions of the U.S. Internal Revenue Code of 1986, as amended (the "Code"). If the factual assumptions or representations made in the request for the private letter ruling prove to have been inaccurate or incomplete in any material respect, then we will not be able to rely on the ruling. Furthermore, the IRS does not rule on whether a distribution such as the spin-off satisfies certain requirements necessary to obtain tax-free treatment under Section 355 of the Code. Rather, the private letter ruling was based on representations by us that those requirements were satisfied, and any inaccuracy in those representations could invalidate the ruling. In connection with the spin-off, we also obtained an opinion of outside counsel, substantially to the effect that, the distribution of shares of MPC common stock in the spin-off qualified as tax free to MPC, us and our stockholders for U.S. federal income tax purposes under Sections 355 and 368 and related provisions of the Code. The opinion relied on, among other things, the continuing validity of the private letter ruling and various assumptions and representations as to factual matters made by MPC and us which, if inaccurate or incomplete in any material respect, would jeopardize the conclusions reached by such counsel in its opinion. The opinion is not binding on the IRS or the courts, and there can be no assurance that the IRS or the courts would not challenge the conclusions stated in the opinion or that any such challenge would not prevail.
If, notwithstanding receipt of the private letter ruling and opinion of counsel, the spin-off were determined not to qualify under Section 355 of the Code, each U.S. holder of our common stock who received shares of MPC common stock in the spin-off would generally be treated as receiving a taxable distribution of property in an amount equal to the fair market value of the shares of MPC common stock received. That distribution would be taxable to each such stockholder as a dividend to the extent of our accumulated earnings and profits as of the effective date of the spin-off. For each such stockholder, any amount that exceeded those earnings and profits would be treated first as a non-taxable return of capital to the extent of such stockholder’s tax basis in its shares of our common stock with any remaining amount being taxed as a capital gain. We would be subject to tax as if we had sold all the outstanding shares of MPC common stock in a taxable sale for their fair market value and would recognize taxable gain in an amount equal to the excess of the fair market value of such shares over our tax basis in such shares.
Under the terms of the Tax Sharing Agreement we entered into with MPC in connection with the spin-off, MPC is generally responsible for any taxes imposed on MPC or us and our subsidiaries in the event that the spin-off and/or certain related transactions were to fail to qualify for tax-free treatment as a result of actions taken, or breaches of representations and warranties made in the Tax Sharing Agreement, by MPC or any of its affiliates. However, if the spin-off and/or certain related transactions were to fail to qualify for tax-free treatment because of actions or failures to act by us or any of our affiliates, we would be responsible for all such taxes.
We may issue preferred stock whose terms could dilute the voting power or reduce the value of Marathon Oil common stock.
Our restated certificate of incorporation authorizes us to issue, without the approval of our stockholders, one or more classes or series of preferred stock having such preferences, powers and relative, participating, optional and other rights, including preferences over Marathon Oil common stock respecting dividends and distributions, as our Board of Directors generally may determine. The terms of one or more classes or series of preferred stock could dilute the voting power or reduce the value of Marathon Oil common stock. For example, we could grant holders of preferred stock the right to elect some number of our directors in all events or on the happening of specified events or the right to veto specified transactions. Similarly, the repurchase or redemption rights or liquidation preferences we could assign to holders of preferred stock could affect the residual value of the common stock.

Item 1B. Unresolved Staff Comments
None.

Item 2. Properties
The location and general character of our principal crude oil and condensate, NGLs and natural gas properties, oil sands mining properties and facilities, and other important physical properties have been described by segment under Item 1. Business.
Estimated net proved crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves are set forth in Item 8. Financial Statements and Supplementary Data – Supplementary Information on Oil and Gas Producing Activities – Estimated Quantities of Proved Oil and Gas Reserves. The basis for estimating these reserves is discussed in Item 1. Business – Reserves.
Item 3. Legal Proceedings
We are a defendant in a number of legal and administrative proceedings arising in the ordinary course of business, including, but not limited to, royalty claims, contract claims, tax disputes and environmental claims. While the ultimate outcome and impact to us cannot be predicted with certainty, we believe the resolution of these proceedings will not have a material adverse effect on our consolidated financial position, results of operations or cash flows.
See Item 8. Financial Statements and Supplementary Data – Note 24 to the consolidated financial statements for a description of such legal and administrative proceedings.
Environmental Proceedings
The following is a summary of certain proceedings involving us that were pending or contemplated as of December 31, 20162017, under federal state and internationalstate environmental laws. Except
Government entities have filed lawsuits in California and New York seeking to hold a wide variety of companies that produce fossil fuels liable for the alleged impacts of the greenhouse gas emissions attributable to those fuels. The lawsuits allege damages as described herein, it is not possible to predict accuratelya result of global warming and the plaintiffs are seeking unspecified damages and abatement under various tort theories. Marathon Oil has been named as a defendant in six of these lawsuits in California, along with numerous other companies. Similar lawsuits may be filed in other jurisdictions. While the ultimate outcome of these matters; however, management’s belief set forth in the first paragraph under Legal Proceedings above takes such matters into account.
In July 2015,and impact to us cannot be predicted with certainty, we received a request for information from the EPA under Section 114 of the Clean Air Act regarding several tank batteries used in our Bakken operations.  We executed a settlement agreement with the North Dakota Department of Health relating to this matter in the fourth quarter of 2016 that includes a base penalty of $294,000 that will be reduced under the terms by mitigating corrective actions.  We do not believe that any penalties or corrective action expenditures that may result from this matterthe claims made against us are without merit and will not have a material adverse effect on our consolidated financial position, results of operationoperations or cash flows. 
In December 2016, we received a letter from the U.K. Department for Business, Energy and Industrial Strategy (“BEIS”) notifying us that they intend to impose a fine of €630,906 for a self-disclosed underreporting of generated carbon dioxide ("CO2") emissions.  We made representations requesting a reduction in this proposed penalty on January 10, 2017. We do not believe that any penalties that may result from this matter will have a material adverse effect on our financial position, results of operation or cash flows. flow.
As of December 31, 2016,2017, we have sites across the country where remediation is being sought under environmental statutes, both federal and state, or where private parties are seeking remediation through discussions or litigation.  Based on currently available information the accrued amount to address the clean-up and remediation costs connected with these sites is not material.
If our assumptions relating to these costs prove to be inaccurate, future expenditures may exceed our accrued amounts. 
Item 4. Mine Safety Disclosures
Not applicable.

PART II
Item 5.   Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities
The principal market on which Marathon Oil common stock is traded is the New York Stock Exchange ("NYSE"). As of January 31, 2017,2018, there were 35,29431,472 registered holders of Marathon Oil common stock.
The following table reflects high and low sales prices for Marathon Oil common stock and the related dividend per share by quarter for the past two years:
2016 20152017 2016
(Dollars per share)High Price   Low Price Dividends   High Price   Low Price Dividends  High Price   Low Price Dividends   High Price   Low Price Dividends  
First Quarter$12.82 $6.73 $0.05 $29.63 $25.47 $0.21$18.18 $14.61 $0.05 $12.82 $6.73 $0.05
Second Quarter$15.27 $10.53 $0.05 $31.19 $25.92 $0.21$16.60 $11.35 $0.05 $15.27 $10.53 $0.05
Third Quarter$16.80 $12.90 $0.05 $25.79 $14.04 $0.21$13.73 $10.77 $0.05 $16.80 $12.90 $0.05
Fourth Quarter$18.80 $12.78 $0.05 $20.18 $12.38 $0.05$17.26 $13.48 $0.05 $18.80 $12.78 $0.05
Full Year$18.80 $6.73 $0.20 $31.19 $12.38 $0.68$18.18 $10.77 $0.20 $18.80 $6.73 $0.20
Dividends – Our Board of Directors intends to declare and pay dividends on Marathon Oil common stock based on our financial condition and results of operations, although it has no obligation under Delaware law or the Restated Certificate of Incorporation to do so. In determining our dividend policy, the Board will rely on our consolidated financial statements. Dividends on Marathon Oil common stock are limited to our legally available funds.
The following table provides information about purchases by Marathon Oil and its affiliated purchaser, during the quarter ended December 31, 2016,2017, of equity securities that are registered by Marathon Oil pursuant to Section 12 of the Securities Exchange Act of 1934:
Period
Total Number of
Shares
Purchased(a)
 
Average
Price Paid
per Share
 
Total Number of
Shares Purchased
as Part of Publicly
Announced Plans
or Programs(b)
 
Approximate
Dollar Value of
Shares that May
Yet Be Purchased
Under the Plans
or Programs(b)
10/01/16 – 10/31/1651,396
 $15.96 
 $1,500,285,529
11/01/16 – 11/30/16919
 $13.20 
 $1,500,285,529
12/01/16 – 12/31/16
 
 
 $1,500,285,529
Total52,315
 $15.91 
  
Period
Total Number of
Shares
Purchased(a)
 
Average
Price Paid
per Share
 
Total Number of
Shares Purchased
as Part of Publicly
Announced Plans
or Programs(b)
 
Approximate
Dollar Value of
Shares that May
Yet Be Purchased
Under the Plans
or Programs(b)
10/01/17 – 10/31/1749,046
 $13.38 
 $1,500,285,529
11/01/17 – 11/30/172,813
 $14.62 
 $1,500,285,529
12/01/17 – 12/31/17
 
 
 $1,500,285,529
Total51,859
 $13.45 
  
(a) 
52,31551,859 shares of restricted stock were delivered by employees to Marathon Oil, upon vesting, to satisfy tax withholding requirements.
(b) 
In January 2006, we announced a $2.0 billion share repurchase program. Our Board of directors subsequently increased the authorization for repurchases under the program by $500 million in January 2007, by $500 million in May 2007, by $2.0 billion in July 2007, and by $1.2 billion in December 2013, for a total authorized amount of $6.2 billion. The remaining share repurchase authorization as of December 31, 20162017 is $1.5 billion. No repurchases were made under the program in 2016.2017.

Item 6.   Selected Financial Data
Year Ended December 31,Year Ended December 31,
(In millions, except per share data)2016 2015 2014 2013 20122017 2016 2015 2014 2013
Statement of Income Data(a)(b)(c)
  
        
      
Revenues$4,031
 $5,522
 $10,846
 $11,325
 $11,966
$4,373
 $3,170
 $4,635
 $9,238
 $9,731
Income (loss) from continuing operations(2,140) (2,204) 969
 931
 856
(830) (2,087) (1,701) 710
 710
Discontinued operations(4,893) (53) (503) 2,336
 1,043
Net income (loss)(2,140) (2,204) 3,046
 1,753
 1,582
(5,723) (2,140) (2,204) 3,046
 1,753
Per Share Data(a)(b)(c)
                  
Basic:                  
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
 $1.32
 $1.21
$(0.97) $(2.55) $(2.51) $1.04
 $1.01
Discontinued operations$(5.76) $(0.06) $(0.75) $3.44
 $1.48
Net income (loss)$(2.61) $(3.26) $4.48
 $2.49
 $2.24
$(6.73) $(2.61) $(3.26) $4.48
 $2.49
Diluted:                  
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
 $1.31
 $1.21
$(0.97) $(2.55) $(2.51) $1.04
 $1.00
Discontinued operations$(5.76) $(0.06) $(0.75) $3.42
 $1.47
Net income (loss)$(2.61) $(3.26) $4.46
 $2.47
 $2.23
$(6.73) $(2.61) $(3.26) $4.46
 $2.47
Statement of Cash Flows Data(b)
                  
Additions to property, plant and equipment related to continuing operations$1,245
 $3,476
 $5,160
 $4,443
 $4,361
$(1,974) $(1,204) $(3,485) $(4,937) $(4,170)
Dividends paid162
 460
 543
 508
 480
170
 162
 460
 543
 508
Dividends per share$0.20 $0.68 $0.80 $0.72 $0.68$0.20
 $0.20
 $0.68
 $0.80 $0.72
Balance Sheet Data at December 31                  
Total assets$31,094
 $32,311
 $35,983
 $35,588
 $35,269
$22,012
 $31,094
 $32,311
 $35,983
 $35,588
Total long-term debt, including capitalized leases6,589
 7,276
 5,295
 6,362
 6,475
5,494
 6,581
 7,268
 5,285
 6,352
(a) 
Includes impairments to producing properties of $229 million, $67 million, $412$381 million, $132 million and $96 million and $371 million in 2017, 2016, 2015, 2014 2013 and 20122013 and impairments to unproved properties of $246 million, $195 million, $964$655 million, $306 million and $572 million and $227 million in 2017, 2016, 2015, 2014 2013 and 20122013 (see Item 8. Financial Statements and Supplementary Data – Note 1310 to the consolidated financial statements). Includes a goodwill impairment of $340 million in 2015 related to the N.A.U.S. E&P reporting unit.unit (see Item 8. Financial Statements and Supplementary Data – Note 1412 to the consolidated financial statements).
(b) 
We closed on the sale of our Canada business in 2017 which resulted in an after-tax non-cash impairment charge of $4.96 billion and our Angola assets and our Norway business in 2014 (see Item 8. Financial Statements and Supplementary Data – Note 65 to the consolidated financial statements). The applicable periods have been recast to reflect as discontinued operations.
(c) 
December 31, 2016 includes the increase of a valuation allowance on certain of our deferred tax assets for $1,346 million (see Item 8. Financial Statements and Supplementary Data – Note 9 to the consolidated financial statements).




Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations
The following discussion and analysis of our financial condition and results of operations should be read in conjunction with the information under Item 8. Financial Statements and Supplementary Data and the other financial information found elsewhere in this Form 10-K. The following discussion includes forward-looking statements that involve certain risks and uncertainties. See "Disclosures Regarding Forward-Looking Statements" (immediately prior to Part I) and Item 1A. Risk Factors.
Each of our segments is organized and managed based upon both geographic location and the nature of the products and services it offers:offers.
North AmericaUnited States E&P – explores for, produces and markets crude oil and condensate, NGLs and natural gas in North America;the United States
International E&P – explores for, produces and markets crude oil and condensate, NGLs and natural gas outside of North Americathe United States and produces and markets products manufactured from natural gas, such as LNG and methanol, in E.G.; and
Oil Sands Mining – mines, extracts and transports bitumen from oil sands deposits in Alberta, Canada, and upgrades the bitumen to produce and market synthetic crude oil and vacuum gas oil.
Executive Summary
During 20162017, we continued to strengthen our efforts onbalance sheet, transform our portfolio and manage our capital and operating cost management, simplifyingcosts. Through multiple financing transactions in 2017, we have reduced total debt by approximately $1.75 billion which will result in a reduction to our future annual interest expense of approximately $115 million. Additionally, we closed on the sale of our Canadian business for approximately $2.5 billion and concentratingacquired acreage in the Permian basin, including over 70,000 net acres in Northern Delaware for approximately $1.9 billion.
As discussed in Item 8. Financial Statements and Supplementary Data – Note 5 to the consolidated financial statements, we closed on the sale of our portfolio,Canadian business, which has been reflected as discontinued operations and maintaining balance sheet strengthis excluded from operations in all periods presented.
Key highlights include the following:
Liquidity and flexibility. In 2016, we achieved $1.3corporate financing
Ended 2017 with liquidity of $4.0 billion, comprised of non-core asset sales$563 million in cash and cash equivalents and an undrawn $3.4 billion revolving credit facility, which allowed uswas increased from $3.3 billion in July 2017. Remaining proceeds of $750 million from the sale of our Canadian business are scheduled to be opportunistic with a high quality acquisition in Oklahoma's STACK play. As a result, we further simplified and concentrated our portfolio to the lower cost, higher margin assets in the U.S. resource plays. Looking ahead, our goal is to return to annual production growth for both the company and U.S. resource plays, within cash flows.
Our 2016 accomplishments are summarized below:
Relentless focus on costs
Reduced 2016 Capital Program spend to $1.1 billion, below $1.4 billion original budget
Reduced production expenses per boe in 2016
North America E&P - 19% reduction to $5.96 per boe
International E&P - 16% reduction to $5.05 per boe
Oil Sands Mining - 24% reduction to $27.89 per boe
Reduced average completed well costs in 2016 by 22% in the Oklahoma Resource Basins and 26% in Eagle Ford compared to 2015
Decreased total general and administrative costs by 18% in 2016 compared to last year
Simplifying and concentrating portfolio
Closed on the Oklahoma STACK acquisition of 61,000 net acres
Concentrated asset base to lower cost, higher margin resource plays by closing on $1.3 billion in non-core asset sales
Strengthened balance sheet
Increased our liquidity to $5.8 billion at December 31, 2016 compared to $4.2 billion at December 31, 2015
Raised net $1.2 billion from an equity offeringreceived in the first quarter of 20162018.
ExpandedIn third quarter 2017, we issued $1 billion of 4.4% senior unsecured notes due in 2027 and redeemed approximately $1.75 billion of debt due in 2017, 2018 and 2019. This offering and redemption reduced our future annual interest expense by approximately $64 million.
In December 2017, we redeemed $1 billion of 5.125% municipal revenue bonds due in 2037 in a refunding transaction that preserved our ability to remarket up to $1 billion of tax-exempt municipal bonds prior to 2037. This redemption reduced our future annual interest expense by approximately $51 million.
Simplifying our portfolio
We closed on the capacitysale of the revolving credit facility from $3.0our Canadian business for approximately $2.5 billion to $3.3with over $1.8 billion in theproceeds received to date and $750 million to be received in first quarter 2018.
We closed on multiple Permian basin acquisitions for approximately $1.9 billion of 2016cash on hand.
Improved our cash-adjusted debt-to-capital ratio to 21% at December 31, 2016 compared to 25% at December 31, 2015
Profitable growth within cash flows
Increased U.S. resource play rig count by 50 percent in fourth quarter of 2016, while remaining under budget,Financial and positioning to resume sequential production growth in the resource plays in the first half of 2017
Our 2016 significant operational updates and financialOperational results included the following:
Operational Updates
Total company2017 net sales volumes from continuing operations are 379 mboed, including Libya, which is 10% higher compared to 2016. This includes a 12% increase in sales volumes from the U.S resource plays to 217 mboed within our United States E&P segment.
Due to improved cost structure and higher sales volumes, our production expense rate in our United States E&P segment decreased 7% to $5.57 per boe in 2017 compared to last year. In our International E&P segment, our production expense rate decreased 14% to $4.33 per boe in 2017 primarily due to an increase in sales volumes in E.G. and Libya.
Added proved reserves of 404 mboed193 mmboe for a reserve replacement ratio from continuing operations of 140%.
Net cash provided by operating activities in 2017 was $2.0 billion, compared to $901 million in 2016
We ended 2016 with 2,096 mmboe primarily as a result of proved reserves, with extension, discoveryimproved price realizations, increased sales volumes and other additions of 304 mmboelower unit production expenses.

Increased

Our net sales volumes by 40%loss per share from continuing operations was $0.97 in 2017 as compared to a net loss per share of $2.55 last year. Included in the Oklahoma Resource Basins as we increased activity on our STACK and SCOOP acreage
Delivered basin-leading well results in the Bakken supported by enhanced completions and advantaged geology, while reducing production expense by approximately 30% year-over-year
Achieved record drilling efficiency in the Eagle Ford and record low completed costs during 2016 while continuing to execute high intensity completions
Completed the Alba B3 Compression project in E.G., extending plateau production and field life
Resumed liftings in Libya in December 2016; Force Majeure lifted in September 2016
Ended the year with 12 rigs operating in the U.S. resource plays
Financial results
20162017 net loss of $2.1 billion versus 2015 net loss of $2.2 billion; included in the loss for 2016:are:
Non-cash charge relatedAn increase in sales and other operating revenues of over 40% to a valuation allowance on our deferred tax assets of $1.3$4.2 billion (see Item 8. Financial Statementsprimarily due to improved price realizations and Supplementary Data – Note 9 to the consolidated financial statements)increased sales volumes.
Reduction in segmentOur sales revenuesvolumes from continuing operations increased 10% while production expense remained flat during 2017 as a result of $1.2 billion with a nearly even split between lower price realizations and decreased sales volumesimproved cost structure.
Non-cash charge of $262Depreciation, depletion and amortization expense increased 10% to $2.4 billion due to our increase in sales volumes from continuing operations.
Exploration and impairment expenses increased by $248 million forto $638 million, year over year, primarily due to non-cash impairment charges on proved and unproved property impairments (Seeproperties primarily as a result of the anticipated sales of certain non-core international assets and due to lower forecasted long-term commodity prices.
Our provision for income taxes was $376 million in 2017 primarily as a result of our full valuation allowance on our net federal deferred tax assets throughout 2017 and the effects of our foreign operations. See Item 8. Financial Statements and Supplementary Data - Note 137 to the consolidated financial statementstatements for additional detail)a discussion of the effects of U.S. Tax Reform Legislation.
Net cash provided by operating activities in 2016 was $1.1 billion, compared to $1.6 billion in 2015, reflecting the lower segment revenues

Outlook
Capital Development Program
Our $2.2$2.3 billion 20172018 Capital Development Program will havebe over 90% allocated to the higher return, lower costour U.S. resource plays. We intendAlmost 60% of this development budget will be allocated to ramp up activity in Oklahoma as we progress our STACK and SCOOP acreage toward full field development, and in the Bakken where our enhanced completions recently achieved record results. Additionally, ourhigh-return Eagle Ford assetand Bakken assets, which have demonstrated step-change performance improvements while operating at scale. Approximately one-third of the development budget will continuebe allocated to focus on driving capital efficiencies.our Northern Delaware and Oklahoma assets, where the majority of drilling activity will be transitioning to multi-well pads, while continuing strategic delineation and appraisal.
Our 20172018 Capital Development Program is broken down by reportable operating segment in the table below:
(In millions)Capital Program
North America E&P$2,107
International E&P64
Oil Sands Mining29
Segment total2,200
Corporate and other25
Total Capital Program$2,225
(In millions)Capital Development Program
United States E&P 
   Eagle Ford$710
   Bakken590
   Oklahoma410
   Northern Delaware380
Total United States E&P$2,090
International E&P and corporate other (a)
210
Total Capital Development Program$2,300
North America E&P(a) – Approximately $2 billion of our 2017 Capital Program is allocated about one-third to each of our three core U.S. resource plays as follows:
Oklahoma Resource Basins - we expect to focus on STACK leasehold retention, STACK delineation and infill pilots in preparation for full field development. We plan to increase our Oklahoma rig count to average approximately 10 rigs in 2017, while bringing 90 to 100 gross operated wells to sales during the year. This includes four to five STACK infill pilots and two SCOOP infill pilots to sales, as well as testing additional secondary horizons.
Eagle Ford - we expect to maintain a six-rig drilling program and bring 155 to 170 gross operated wells to sales during 2017. With about two-thirds of the program focused in the high margin oil window, we plan to continue optimizing completion techniques with increased proppant and fluid loading, and average lateral lengths.
Bakken - we plan to focus on our highest return West and East Myrmidon areas where we completed several basin-leading wells in 2016. We will progress multiple enhanced completion trials as well as continue our focus on optimizing base production, while bringing 70 to 75 gross operated wells to sales during 2017. We expect to average approximately six drilling rigs in the Bakken in 2017.
International E&P Oil Sands Mining, Corporateand corporate other includes our International E&P segment and other corporate items ��� Less than 10% of our Capital Program will be allocated to these segments for sustaining capital projects.

Operations
Our net sales volumes from continuing operations, including Libya, averaged 404379 mboed, 438345 mboed and 415385 mboed for 2017, 2016 and 2015, respectively. This 10% increase in 2017 was primarily due to new wells to sales in our U.S. resource plays, our acquisitions in Northern Delaware and 2014. Netthe resumption of sales in Libya.
The following table presents a summary of our sales volumes from continuing operations decreased by 8%for each of our segments. Refer to 404 mboed in 2016 relating to dispositionsthe Results of certain non-core assets (23 mboed from Wyoming, West Texas, East Texas, North Louisiana and GulfOperations section for a price-volume analysis for each of Mexico) during the comparison period as well as lower completion activity in the U.S resource plays. As liftings from Libya were sporadic during this 3-year period, a more representative comparison is net sales volumes from continuing operations excluding Libya, which was 401 mboed, 438 mboed and 408 mboed for 2016, 2015 and 2014. The table below provides additional detail regarding net sales volumes by segment:segments.
Net Sales Volumes2016 Increase
(Decrease)
 2015 Increase
(Decrease)
 2014
North America E&P (mboed)
223 (17)% 269 13 % 238
International E&P (mboed)
122 5 % 116 (9)% 127
Oil Sands Mining (mbbld) (a)
59 11 % 53 6 % 50
Total Continuing Operations (mboed)
404 (8)% 438 6 % 415
Net Sales Volumes2017 Increase
(Decrease)
 2016 Increase
(Decrease)
 2015
United States E&P (mboed)
234 5% 223 (17)% 269
International E&P (a) (mboed)
145 19% 122 5 % 116
Total Continuing Operations (mboed)
379 10% 345 (10)% 385
(a)     Includes blendstocks.Years ended December 31, 2017, 2016 and 2015 include net sales volumes relating to Libya of 20 mboed, 3 mboed and none, respectively.






North AmericaUnited States E&P
The following tables provide additional detail regarding net sales volumes, sales mix and operational drilling activity:activity for our significant operations within this segment:
Net Sales Volumes2016 Increase
(Decrease)
 2015 Increase
(Decrease)
 20142017 Increase
(Decrease)
 2016 Increase
(Decrease)
 2015
Oklahoma Resource Basins35 40% 25 39% 18
Equivalent Barrels (mboed)
 
Oklahoma54 54% 35 40% 25
Eagle Ford105 (22)% 134 20% 112101 (4)% 105 (22)% 134
Bakken54 (8)% 59 16% 5156 4% 54 (8)% 59
Other North America(a)
29 (43)% 51 (11)% 57
Total North America E&P (mboed)
223 (17)% 269 13% 238
Northern Delaware6 100%  —% 
Other United States(a)
17 (41)% 29 (43)% 51
Total United States E&P (mboed)234 5% 223 (17)% 269
(a)
(a) Year ended December 31, 2017 includes decreases of 14 mboed, consisting of the disposition of Wyoming and certain non-operated CO2 and waterflood assets in West Texas and New Mexico in 2016. Year ended December 31, 2016 decreases relating to assets sold were 23 mboed, primarily consisting of Wyoming, West Texas, East Texas, North Louisiana and certain Gulf of Mexico assets.
Sales Mix - U.S. Resource Plays - 2016 Oklahoma Resource Basins Eagle Ford Bakken Total
Crude oil and condensate 25% 57% 81% 58%
Natural gas liquids 26% 21% 11% 19%
Natural gas 49% 22% 8% 23%
Drilling Activity - U.S. Resource Plays2016 2015 2014
Gross Operated     
Oklahoma Resource Basins:     
Wells drilled to total depth33 20 19
Wells brought to sales28 21 18
Eagle Ford:     
Wells drilled to total depth168 251 360
Wells brought to sales168 276 310
Bakken:     
Wells drilled to total depth3 35 83
Wells brought to sales13 56 69
In 2016, we continued to focus on our U.S. unconventional resource plays. We acquired 61,000 net surface acres in the STACK play in Oklahoma, delivered basin-leading well results in the Bakken and further improved returns in the Eagle Ford with cost reductions, efficiency gains and enhanced completions. North America E&P segment average net sales volumes in 2016 decreased 17% when compared to 2015 largely as a result of the aforementioned dispositions in Wyoming, East Texas, North Louisiana and certain Gulf of Mexico as well as base declines due to reduced completion activity. This decrease was partially offset by increases dueassets. See Item 8. Financial Statements and Supplementary Data - Note 5 to the Oklahoma STACK acquisition in the second-half of 2016.
Oklahoma Resource Basins – During 2016 we brought 28 gross wells to sales, of which 20 were in the STACK Meramec, 6 were in the SCOOP Woodford and 2 were in the SCOOP Springer. We increased activity during the year from two to five rigs, and focused on protecting our valuable acreage through leasehold drilling, delineation activity, and enhancing well performance through enhanced completion designs.  We also pursued technical advancement through data collection, analysis and participation in several infill spacing pilots.  consolidated financial statements for information about these dispositions.
In 2016, we drilled our first operated spacing pilot in the STACK Meramec and we expect those wells to come to sales in the first quarter of 2017. At year-end 2016, approximately 70% of our STACK leasehold was held by production and approximately 90% of our SCOOP acreage was held by production.
Sales Mix - U.S. Resource Plays - 2017 Oklahoma Eagle Ford Bakken Northern Delaware Total
Crude oil and condensate 28% 58% 83% 66% 57%
Natural gas liquids 26% 21% 10% 8% 19%
Natural gas 46% 21% 7% 26% 24%
Drilling Activity - U.S. Resource Plays2017 2016 2015
Gross Operated     
Oklahoma:     
Wells drilled to total depth86 33 20
Wells brought to sales73 28 21
Eagle Ford:     
Wells drilled to total depth182 168 251
Wells brought to sales157 168 276
Bakken:     
Wells drilled to total depth90 3 35
Wells brought to sales39 13 56
Northern Delaware     
Wells drilled to total depth27  
Wells brought to sales18  
Eagle Ford - In 2016 we– Our net sales volumes were 101 mboed in 2017, 4% lower compared to 2016. We brought 168 grossfewer wells to sales of which 90 were in the Lower Eagle Ford, 53 were in the Upper Eagle Ford,2017, while we increased well productivity through completion optimization and 25 were in the Austin Chalk.  We continued efforts to utilize technology and drive efficiencies into the drilling process resulting in an average spud-to-TD of 7.9 days in 2016, compared to 10.6 days in 2015.  Record low average completed well costs of $3.9 million per well were achieved the fourth quarter of 2016 (down 20 percent from year-ago quarter), despite increasing proppant loading per lateral foot by more than 70 percent compared to fourth quarter 2015.efficiency gains.
BakkenOur net sales volumes were 56 mboed in 2017 compared to 54 mboed in 2016. In 20162017, we brought 13 wells to sales,improved well performance with continued application of which 7 werehigh intensity completions. During the year, we set a new record in the Middle Bakken formation and 6 were inWilliston Basin for the Three Forks formation. We realized well performance improvements through high intensity completions and targeted application ofhighest 30-day initial production oil rate.

diversion techniques.  In 2016, Myrmidon wells were pumped with 6 to 18 million pounds of proppant with 40 to 50 stages per well. Since December, we have mobilized four rigs to Myrmidon to support the development program.
North America E&P segment averageOklahoma – Our net sales volumes in 20152017 increased 13% whenby 54% to 54 mboed compared to 2014. Net liquid hydrocarbonyear ended 2016. Our activity during 2017 was concentrated in the STACK and was focused on leasehold capture, delineation drilling and infill spacing pilots.
Northern Delaware – Our net sales volumes increased 24 mbbldwere 6 mboed in 2017 which reflected a partial year of production following the second quarter 2017 closing of the BC Operating and net natural gas sales volumes increased 41 mmcfdBlack Mountain assets. During 2017 we focused our activity on delineation and leasehold capture across our position in 2015 primarily reflecting continued growth from our three core U.S. resource plays.Eddy and Lea Counties, New Mexico.

International E&P
The following table provides net sales volumes from continuing operations:operations within this segment:
Net Sales Volumes2016 Increase
(Decrease)
 2015 Increase
(Decrease)
 20142017 Increase
(Decrease)
 2016 Increase
(Decrease)
 2015
Equivalent Barrels (mboed)
          
Equatorial Guinea102 5% 97 (7)% 104109 7% 102 5% 97
United Kingdom(a)
17 (11)% 19 19% 1614 (18)% 17 (11)% 19
Libya3 100%  (100)% 720 567% 3 100% 
Other International2 100%  —% 
Total International E&P (mboed)
122 5% 116 (9)% 127145 19% 122 5% 116
Net Sales Volumes of Equity Method Investees 
  
 
Equity Method Investees 
  
 
LNG (mtd)
5,874 —% 5,884 (10)% 6,5356,423 9% 5,874 —% 5,884
Methanol (mtd)
1,358 45% 937 (14)% 1,0921,374 1% 1,358 45% 937
Condensate & LPG (boed)
13,430 10% 12,208 (40)% 20,50614,501 8% 13,430 10% 12,208
(a)     Includes natural gas acquired for injection and subsequent resale of 5 mmcfd, 8 mmcfd and 6 mmcfd for 2016, 2015, and 2014.resale.
International E&P segment average netEquatorial Guinea – Net sales volumes in 2016 increased 5% when compared to 2015. Sales volumes in E.G.2017 were higher due tothan 2016 as a result of the completion and start-up of theour Alba field compression project which extendsin mid-2016 and lower volumes in first quarter 2016 due to a planned turnaround. Additionally, in April 2017 we received host government approval to develop Block D offshore E.G. through unitization with the production plateau and field life.Alba field.
In the U.K., theUnited Kingdom – Net sales volumes slightlyin 2017 decreased compared to 2016 primarily as a result of downtimeplanned turn-around activity at the Brae and Foinaven complexes and the temporary shut-down of the outside-operated Forties Pipeline System during fourth quarter 2017.
Libya – While civil and political unrest has interrupted operations in recent years, our production resumed in October 2016. During December 2016, liftings resumed from the first quarter of 2016.
International E&P segment average netEs Sider crude oil terminal. During 2017, sales volumes and production continued, except for a brief interruption in 2015 decreased 9% when comparedMarch 2017 due to 2014. There were no liftings in Libya during 2015 as a result of ongoing civil unrest. Sales volumes in E.G. were lower due to a series of turnarounds and other maintenance activities performed at the Alba field, E.G. LNG and AMPCO facilities during the year. In the U.K., sales volumes increased as we completed the five-well Brae infill drilling program that began in 2014.
Oil Sands Mining
 Our OSM operations consist of a 20% non-operated working interest in the AOSP.  Our net synthetic crude oil sales volumes were 59 mbbld in 2016 compared to 53 mbbld in 2015 and 50 mbbld in 2014. The 2016 increase was a result of strong mine and upgrader performance coupled with less planned maintenance.
We've continued our alignment with the operator and other partners to focus on reducing the mine's cost and increasing reliability. As a result, there has been noticeable impact on the mine's cost structure with a 24% reduction in production expense to $27.89 per bbl for 2016 compared to 2015. See Item 7 Management's Discussion and Analysis of Financial Condition and Results of Operations for the 2016 compared to 2015 for additional detail on production expenses.


Market Conditions
OilCrude oil, natural gas and gasNGL benchmarks declined during 2016 andincreased in 2017 as compared to the same period in 2016. As a result, we experienced declines in ourincreased price realizations associated with those benchmarks. Although weWe continue to expect crude oil, natural gas and NGLs benchmark prices to remain volatile based on global supply and demand, prices have improved subsequent to December 31, 2016.which will result in increases or decreases in our price realizations. See Item 1A. Risk Factors and Item 7. Management’s Discussion and Analysis of Financial Condition – Critical Accounting Estimates for further discussion of how a further declinedeclines in commodity prices could impact us. Additional detail on market conditions, including our average price realizations and benchmarks for crude oil, NGLs and natural gas relative to our operating segments, follows.
North America
United States E&P
 The following table presents our average price realizations and the related benchmarks for crude oil, NGLs and natural gas for 2017, 2016 2015 and 2014:2015:
 2016 Increase (Decrease) 2015Decrease 2014 2017 Increase (Decrease) 2016 Increase (Decrease) 2015
Average Price Realizations (a)
                   
Crude Oil and Condensate (per bbl) (b)
 
$38.57
 (11)% 
$43.50
(49)% 85.25
 
$49.35
 28% 
$38.57
 (11)% 43.50
Natural Gas Liquids (per bbl)
 13.15
 (2)% 13.37
(60)% 33.42
 20.55
 56% 13.15
 (2)% 13.37
Total Liquid Hydrocarbons (per bbl)
 32.71
 (14)% 37.85
(51)% 77.02
 42.31
 29% 32.71
 (14)% 37.85
Natural Gas (per mcf) (c)
 2.38
 (11)% 2.66
(42)% 4.57
 2.84
 19% 2.38
 (11)% 2.66
Benchmarks   

  

     

   

  
WTI crude oil average of daily prices (per bbl)
 
$43.47
 (11)% 
$48.76
(48)% 92.91
 
$50.85
 17% 
$43.47
 (11)% 48.76
LLS crude oil average of daily prices (per bbl)
 45.02
 (14)% 52.33
(46)% 96.64
 54.04
 20% 45.02
 (14)% 52.33
Mont Belvieu NGLs (per bbl) (d)
 17.40
 3 % 16.94
(48)% 32.52
 23.76
 37% 17.40
 3 % 16.94
Henry Hub natural gas settlement date average (per mmbtu)
 2.46
 (8)% 2.66
(40)% 4.42
 3.11
 26% 2.46
 (8)% 2.66
(a) 
Excludes gains or losses on commodity derivative instruments.
(b) 
Inclusion of realized gains on crude oil derivative instruments would have increased average liquid hydrocarbon price realizations per barrel by $0.75, $0.92, and $1.24 for 2017, 2016, and 2015. There were no crude oil derivative instruments for 2014.
(c) 
Inclusion of realized gains (losses) on natural gas derivative instruments would have a de minimusminimal impact on average price realizations for the periods presented.
(d) 
Bloomberg Finance LLP: Y-grade Mix NGL of 50% ethane, 25% propane, 10% butane, 5% isobutane and 10% natural gasoline.
Crude oil and condensate – Our crude oil and condensate price realizations may differ from the benchmark due to the quality and location of the product.
Natural gas liquids – The majority of our NGLs volumes are sold at reference to Mont Belvieu prices.
Natural gas A significant portion of our natural gas production in the U.S. is sold at bid-week prices, or first-of-month indices relative to our specific producing areas.  
International E&P
The following table presents our average price realizations and the related benchmark for crude oil for 2017, 2016 2015 and 2014:2015:
 2016 Decrease 2015 Increase (Decrease) 2014 2017 Increase (Decrease) 2016 (Decrease) 2015
Average Price Realizations                    
Crude Oil and Condensate (per bbl)
 
$41.70
 (12)% 
$47.50
 (46)% 
$87.23
 
$53.05
 27% 
$41.70
 (12)% 
$47.50
Natural Gas Liquids (per bbl)
 2.11
 (25)% 2.81
 14 % 2.46
 3.15
 49% 2.11
 (25)% 2.81
Total Liquid Hydrocarbons (per bbl)
 32.10
 (12)% 36.67
 (47)% 68.98
 43.36
 35% 32.10
 (12)% 36.67
Natural Gas (per mcf)
 0.52
 (24)% 0.68
 (6)% 0.72
 0.55
 6% 0.52
 (24)% 0.68
Benchmark   

   

     

   

  
Brent (Europe) crude oil (per bbl)(a)
 
$43.55
 (17)% 
$52.35
 (47)% 
$99.02
 
$54.25
 25% 
$43.55
 (17)% 
$52.35
(a) 
Average of monthly prices obtained from EIAthe United States Energy Information Agency website.

Our U.K. liquid hydrocarbon production is generally sold in relation to the Brent crude benchmark. Our production from the Alba field in E.G. is condensate and gas. Condensate is sold at market prices.prices and the gas is shipped to the onshore Alba Plant. The Alba Plant extracts NGLs and secondary condensate, from gas,which have been supplied under a long-term contract at a fixed price, leaving dry natural gas. The processedextracted NGLs and secondary condensate are sold by Alba Plant at market prices, with our share of its income/loss reflected in Incomeincome from equity method investments. Theinvestments, and the dry natural gas from Alba Plant is supplied to AMPCO and EGHoldings under long-term contracts at fixed prices; therefore,prices. Therefore, our reported average realized prices for condensate, NGLs and natural gas will not fully track market price movements. Because of the location and limited local demand for natural gas in E.G., we consider the prices under the contracts with Alba Plant LLC, EGHoldings and AMPCO to be comparable to the price that could

be realized from transactions with unrelated parties in this market under the same or similar circumstances. EGHoldings and AMPCO process the gas into LNG and methanol, which are sold at market prices, with our share of their income/loss reflected in the Incomeincome from equity method investments line item on the Consolidated Statements of Income. Although uncommon, any dry gas not sold is returned offshore and re-injected into the Alba field for later production.
Oil Sands Mining
 The Oil Sands Mining segment produces and sells various qualities of synthetic crude oil. Output mix can be impacted by operational reliability or planned unit outages at the mines or upgrader. Sales prices for synthetic crude oil historically tracked movements in the WTI crude oil and the WCS Canadian heavy crude oil benchmarks. The influence of each benchmark can change from period to period based on market dynamics.
The following table presents our average price realizations and the related benchmarks that impacted both our revenues and variable costs for 2016, 2015 and 2014:
  2016 Decrease 2015 
Decrease
 2014
Average Price Realizations          
Synthetic Crude Oil (per bbl)
 
$37.57
 (6%) 
$40.13
 (52%) 
$83.35
Benchmark   

   

  
WTI crude oil average of daily prices (per bbl)
 
$43.47
 (11%) 
$48.76
 (48%) 
$92.91
WCS crude oil (per bbl)(a)
 29.48
 (16%) 35.28
 (52%) 73.60
(a)
Average of monthly prices based upon average WTI adjusted for differentials unique to western Canada.


Consolidated Results of Operations: 20162017 compared to 20152016
Sales and other operating revenues, including related party are summarized by segment in the following table:
Year Ended December 31,Year Ended December 31,
(In millions)2016201520172016
Sales and other operating revenues, including related party  
North America E&P$2,375
$3,358
United States E&P$3,138
$2,375
International E&P665
728
1,154
665
Oil Sands Mining823
815
Segment sales and other operating revenues, including related party3,863
4,901
4,292
3,040
Unrealized gain (loss) on commodity derivative instruments(110)50
(81)(110)
Sales and other operating revenues, including related party$3,753
$4,951
$4,211
$2,930

Below is a price/volume analysis for each segment. Refer to the preceding Operations and Market Conditions sections for additional detail related to our net sales volumes and average price realizations.
 Year Ended December 31, Increase (Decrease) Related to Year Ended December 31, Year Ended December 31, Increase (Decrease) Related to Year Ended December 31,
(In millions) 2015 Price Realizations Net Sales Volumes 2016 2016 Price Realizations Net Sales Volumes 2017
North America E&P Price-Volume Analysis (a)
United States E&P Price-Volume Analysis (a)United States E&P Price-Volume Analysis (a)
Liquid hydrocarbons $2,905
 $(321) $(543) $2,041
 $2,041
 $619
 $66
 $2,726
Natural gas 341
 (32) (35) 274
 274
 58
 29
 361
Realized gain on commodity                
derivative instruments 78
 

   44
 44
 

   45
Other sales 34
     16
 16
     6
Total $3,358
     $2,375
 $2,375
     $3,138
International E&P Price-Volume Analysis
Liquid hydrocarbons $578
 $(78) $46
 $546
 $546
 $264
 $205
 $1,015
Natural gas 108
 (25) 4
 87
 87
 4
 6
 97
Other sales 42
     32
 32
     42
Total $728
     $665
 $665
     $1,154
Oil Sands Mining Price-Volume Analysis
Synthetic crude oil $781
 $(61) $95
 $815
Other sales 34
     8
Total $815
     $823
(a) Year ended December 31, 20152016 includes 23sales volumes of 14 mboed on an annualized basis relating to assets sold that are not contributing sales volumes in all or a portion of 2016,when compared to 2017, primarily consisting of the disposition of Wyoming East Texas, North Louisiana and certain Gulf ofnon-operated CO2 and waterflood assets in West Texas and New Mexico assets.in 2016.
Marketing revenues decreased $293$78 million in 2017 from 2016, primarily as a result of lower marketed volumes in the United States E&P segment due to non-core asset dispositions. Marketing activities include the purchase of commodities from third parties for resale and serve to aggregate volumes in order to satisfy transportation commitments as well as to achieve flexibility within product types and delivery points. Since the volume of marketing activity is based on market dynamics, it can fluctuate from period to period.
Income from equity method investments increased $81 million primarily due to higher price realizations from LPG at our Alba plant and methanol at our AMPCO methanol facility. Also contributing to the increase was improvement in net sales volumes primarily driven by the completion of the Alba field compression project in E.G. during the second half of 2016.
Net gain on disposal of assetsdecreased $331 million in 2017 from 2016. This decrease was primarily related to the sale of non-core assets in the first half of 2016 in Wyoming, West Texas and New Mexico, and the Gulf of Mexico. See Item 8. Financial Statements and Supplementary Data - Note 5 to the consolidated financial statements for information about these dispositions.
Other income increased $25 million in 2017 from 2016. This increase was primarily a result of a downward revision in U.K. estimated asset retirement costs as well as timing of abandonment activities in the U.K. See Item 8. Financial Statements and Supplementary Data - Note 11 to the consolidated financial statements for detail about our asset retirement obligation.
Production expensesremained nearly flat during 2017 while our sales volumes from continuing operations increased. During 2017, our production expense rate (expense per boe) for United States E&P was lower primarily due to the disposition of higher cost non-core assets in Wyoming. The International E&P expense rate decreased in the year of 2017 primarily due to

an increase in sales volumes in E.G. and Libya, combined with lower maintenance costs in E.G.
($ per boe)20172016
Production Expense Rate  
United States E&P
$5.57

$5.96
International E&P
$4.33

$5.05
Marketing expenses decreased $77 million in 2017 from the prior year, consistent with the decrease in marketing revenues discussed above.
Other operating expenses decreased $53 million compared to 2016 which included the termination payment of our Gulf of Mexico deepwater drilling commitment in 2016.
Exploration expenses increased $86 million during 2017 versus the comparable 2016 period, due primarily to charges taken as a result of lower forecasted long-term commodity prices and the anticipated sales of certain non-core properties in our International E&P segment. In 2017, we recorded non-cash charges of $159 million comprised of $95 million in unproved property impairments in our International E&P segment and $64 million in dry well costs related to our Diaba License G4-223 in the Republic of Gabon. Additionally, our decision not to develop the Tchicuate offshore Block in the Republic of Gabon resulted in an increase to exploration expenses of $43 million during 2017. Unproved property impairments during 2016 primarily consist of non-cash charges related to our decision to not drill our remaining Gulf of Mexico leases.
The following table summarizes the components of exploration expenses:
 Year Ended December 31,
(In millions)20172016
Exploration Expenses  
Unproved property impairments$246
$195
Dry well costs77
25
Geological and geophysical25
5
Other61
98
Total exploration expenses$409
$323
Exploration expenses are also discussed in Item 8. Financial Statements and Supplementary Data - Note 10 to the consolidated financial statements.
Depreciation, depletion and amortizationincreased $216 million in 2017 from the prior year primarily as a result of an increase of $176 million in the United States E&P due to a 5% increase in net sales volumes, and an increase in the DD&A rates within our U.S. resource plays. Also contributing to this higher expense was an increase of $52 million in our International E&P segment resulting from increased sales volumes due to the completion and start-up of our E.G. Alba field compression project in mid-2016, and the resumption of sales volumes and production in Libya. Our segments apply the units-of-production method to the majority of their assets, including capitalized asset retirement costs; therefore, volumes have an impact on DD&A expense.
The DD&A rate (expense per boe), which is impacted by field-level changes in sales volumes, reserves and capitalized costs, can also cause changes to our DD&A. The DD&A rate for United States E&P increased primarily due to the sales volume mix between our U.S. resource plays, and the outside-operated Gunflint field achieving first production in mid-2016. Also contributing to the increase was a reduction to the Eagle Ford proved developed reserve base in the fourth quarter of 2016. The DD&A rate for International E&P remained relatively consistent with the 2016 rate. The following table provides DD&A rates for each segment.
($ per boe)20172016
DD&A rate  
United States E&P
$23.51

$22.49
International E&P
$6.19

$6.21
Impairments increased $162 million in 2017 from the comparable 2016 period. This increase was primarily consisting of $136 million of proved property impairments in certain non-core properties in our International E&P segment as a result of our anticipated sales and lower forecasted long-term commodity prices. Additionally, included in proved property impairments was $89 million in 2017 and $67 million in 2016, both relating to lower forecasted commodity prices in conventional properties in Oklahoma and the Gulf of Mexico.

See Item 8. Financial Statements and Supplementary Data - Note 10 to the consolidated financial statement for additional detail.
Taxes other than incomeincludes production, severance and ad valorem taxes, primarily in the U.S., which tend to increase or decrease in relation to revenue and sales volumes. Taxes other than income increased $32 million in the current year as a result of increased revenue and sales volumes, and due to a reserve being established for non-income tax examinations relating to open tax years. The following table summarizes the components of taxes other than income:
 Year Ended December 31,
(In millions)20172016
Taxes other than income  
Production and severance$121
$91
Ad valorem13
23
Other49
37
Total$183
$151
General and administrative expenses decreased$81 million in 2017 primarily due to reduced pension settlement charges of $32 million in 2017 compared to $103 million in 2016.
Net interest and otherdecreased $62 million during 2017 primarily as a result of the termination of our forward starting interest rate swaps, which resulted in a gain of $47 million. Additionally, during 2017 we reduced total long term debt by approximately $1.75 billion which resulted in a reduction to our net interest and other. The components of net interest and other are detailed in Item 8. Financial Statements and Supplementary Data - Note 15 to the consolidated financial statements.
Loss on early extinguishment of debt increased $51 million in 2017 primarily due to make-whole call provisions of $46 million paid upon the redemption of approximately $1.75 billion in senior unsecured notes. See Item 8. Financial Statements and Supplementary Data - Note 15 to the consolidated financial statements for further detail.
Provision (benefit) for income taxesreflects an effective tax rate from continuing operations of 83% and 79% for 2017 and 2016. In 2017, our tax expense was primarily a result of our full valuation allowance on our net federal deferred tax assets throughout 2017 and the effects of our foreign operations.
See Item 8. Financial Statements and Supplementary Data - Note 7 to the consolidated financial statements for a discussion of the effective income tax rate.
Discontinued operations are presented net of tax. See Item 8. Financial Statements and Supplementary Data - Note 5 to the consolidated financial statements for financial information concerning our discontinued operations.

Segment Results: 2017 compared to 2016
Segment income(loss)
Segment income (loss) represents income (loss) from operations excluding certain items not allocated to segments, net of income taxes, attributable to the operating segments. A portion of our corporate and operations support general and administrative costs are not allocated to the operating segments. Gains or losses on dispositions, certain impairments, unrealized gains or losses on commodity derivative instruments, pension settlement losses, or other items that affect comparability also are not allocated to operating segments.
The following table reconciles segment income (loss) to net income (loss):
 Year Ended December 31,
(In millions)2017 2016
United States E&P$(148) $(415)
International E&P374
 228
Segment income (loss)226
 (187)
Items not allocated to segments, net of income taxes (a)
(1,056) (1,900)
    Income (loss) from continuing operations(830) (2,087)
    Income (loss) from discontinued operations (b)
(4,893) (53)
         Net income (loss)$(5,723) $(2,140)
(a) See Item 8. Financial Statements and Supplementary Data - Note 6 to the consolidated financial statements for further detail about items not allocated to segments.
(b) We sold our Canadian business in the second quarter of 2017. The Canadian business is reflected as discontinued operations in all periods presented.
 United States E&P segment loss decreased $267 million in 2017 compared to 2016 primarily due to higher price realizations and higher sales volumes. Partially offsetting this revenue increase was an increase in DD&A and a decrease in the income tax benefit, as we did not realize a tax benefit on any net federal deferred tax assets generated in 2017 due to the full valuation allowance on net federal deferred tax assets in the prior year.
International E&P segment incomeincreased $146 million in 2017 compared to 2016 primarily due to higher price realizations, and an increase in sales volumes in E.G. and Libya. This was partially offset by an increase in DD&A and income tax expense as a result of the increase in sales volumes.

Consolidated Results of Operations: 2016 compared to 2015
Sales and other operating revenues, including related partyare summarized by segment in the following table:
 Year Ended December 31,
(In millions)20162015
Sales and other operating revenues, including related party  
United States E&P$2,375
$3,358
International E&P665
728
Segment sales and other operating revenues, including related party3,040
4,086
Unrealized gain on crude oil derivative instruments(110)50
Sales and other operating revenues, including related party$2,930
$4,136
Below is a price/volume analysis for each segment. Refer to the preceding Operations and Market Conditions sections for additional detail related to our net sales volumes and average price realizations.
  Year Ended December 31, Increase (Decrease) Related to Year Ended December 31,
(In millions) 2015 Price Realizations Net Sales Volumes 2016
United States E&P Price-Volume Analysis
Liquid hydrocarbons $2,905
 $(321) $(543) $2,041
Natural gas 341
 (32) (35) 274
Realized gain on crude oil        
    derivative instruments 78
 

   44
Other sales 34
     16
Total $3,358
     $2,375
International E&P Price-Volume Analysis
Liquid hydrocarbons $578
 $(78) $46
 $546
Natural gas 108
 (25) 4
 87
Other sales 42
     32
Total $728
     $665
Marketing revenues decreased $259 million in 2016 from 2015. Marketing activities include the purchase of commodities from third parties for resale and serve to aggregate volumes in order to satisfy transportation commitments as well as to achieve flexibility within product types and delivery points. Since the volume of marketing activity is based on market dynamics, it can fluctuate from period to period. The decreases are primarily related to lower marketed volumes in North America,the United States, which were further compounded by a lower commodity price environment.
Income from equity method investmentsincreased $30 million primarily due to higher net sales volumes in the second half of 2016 atin E.G. as a result of the completion of the Alba field compression project. Additionally, a partial impairment of our investment in an equity method investee in 2015 of $12 million contributed to the increase in the current year.
Net gain on disposal of assetsincreased $269 million in 2016 from 2015. See Item 8. Financial Statements and Supplementary Data - Note 65 to the consolidated financial statements for information about these dispositions.
Production expenses decreased $381$267 million in 2016 from 2015. North AmericaUnited States E&P declined $238 million primarily due to lower operational, maintenance and labor costs, coupled with lower net sales volumes resulting from the impact of our non-core asset dispositions and lower activity levels. International E&P declined $29 million largely due to lower operational and maintenance costs as well as a more favorable exchange rate on expenses. OSM decreased $114 million primarily due to continued lower turnaround costs, cost management, specifically staffing and contract labor, and a favorable exchange rate on expenses denominated in foreign currencies.

The 2016 production expense rate (expense rate per boe) for North AmericaUnited States E&P declined primarily due to cost reductions that occurred at a rate faster than our production decline. The International E&P expense rate decreased in 2016 primarily due to reduced maintenance and project costs in the U.K. and benefited from the favorable exchange rate. The OSM expense rate decreased in 2016 primarily due to lower operational costs and the favorable exchange rate. The following table provides production expense rates for each segment:

($ per boe)20162015
North America E&P
$5.96

$7.38
International E&P
$5.05

$5.99
Oil Sands Mining (a)

$27.89

$36.48
(a) Production expense per synthetic crude oil barrel (before royalties) includes production costs, shipping and handling, taxes other than income and insurance costs and excludes pre-development costs.
($ per boe)20162015
Production Expense Rate  
United States E&P
$5.96

$7.38
International E&P
$5.05

$5.99
Marketing expenses decreased $287$255 million in 2016 from the prior year, consistent with the decrease in marketing revenues discussed above.
Other operating expenses increased $73$74 million primarily as a result of the termination payment of our Gulf of Mexico deepwater drilling rig.commitment.
 Exploration expenses decreased $988648 million in 2016 compared to 2015, reflecting our strategic decision to transition out of conventional exploration. In 2016, unproved property impairments primarily consisted of non-cash charges related to our decision to not drill our remaining Gulf of Mexico leases and also included certain other unproved properties in North America.the United States. In 2015, unproved property impairments are due to changes in our conventional exploration strategy (Gulf of Mexico Canadian in-situ assets and the Harir block in the Kurdistan Region of Iraq), and the sale of certain properties in the Gulf of Mexico, as well as our unproved property in Colorado.
Dry well costs in 2015 included the operated Solomon exploration well in the Gulf of Mexico and our operated Sodalita West #1 exploratory well in E.G., and suspended well costs related to our Canadian in-situ assets at Birchwood.
The following table summarizes the components of exploration expenses:
Year Ended December 31,Year Ended December 31,
(In millions)2016201520162015
Exploration Expenses 
Unproved property impairments$195
$964
$195
$655
Dry well costs32
250
25
212
Geological and geophysical5
31
5
31
Other98
73
98
73
Total exploration expenses$330
$1,318
$323
$971
Exploration expensesexpense are also discussed in Item 8. Financial Statements and Supplementary Data - Note 1310 to the consolidated financial statements.
Depreciation, depletion and amortizationdecreased $562$565 million in 2016 from the prior year primarily as a result of net sales volume decreases in the North AmericaUnited States E&P segment, including the impact of non-core asset dispositions, and volume declines due to base declines and lower completion activity. Our segments apply the units-of-production method to the majority of their assets, including capitalized asset retirement costs; therefore, volumes have an impact on DD&A expense.
The DD&A rate (expense per boe), which is impacted by field-level changes in sales volumes, reserves and capitalized costs, can also cause changes to our DD&A. The following table provides DD&A rates for each segment. The DD&A rate for North AmericaUnited States E&P decreased primarily due to a higher proved reserve base. The DD&A rate for International E&P declined primarily due to sales volume mix changes in E.G. and the U.K. for 2016.
($ per boe)2016201520162015
North America E&P
$22.49

$24.24
DD&A rate 
United States E&P
$22.49

$24.24
International E&P
$6.21

$6.95

$6.21

$6.95
Oil Sands Mining
$11.32

$12.48
 Impairments decreased $685$654 million in 2016 versus 2015. Impairments in 2016 were primarily the result of lower forecasted commodity prices in conventional properties in Oklahoma and the Gulf of Mexico, and were also the result of revisions to estimated abandonment costs. Impairments in 2015 included $340 million for the goodwill impairment of the North AmericaUnited States E&P reporting unit, and $335 million related to proved properties (primarily in Colorado and the Gulf of Mexico) as a result of lower forecasted commodity prices, and $44 million associated with our disposition of natural gas assets in East Texas, North Louisiana and Wilburton, Oklahoma.

See Item 8. Financial Statements and Supplementary Data - Note 1310 and Note 1412 to the consolidated financial statement for additional detail. 

Taxes other than income includes production, severance and ad valorem taxes, primarily in the U.S., which tend to increase or decrease in relation to revenue and sales volumes. The decline in revenue and sales volumes during 2016 resulted in a decline of $66$65 million compared to 2015. The following table summarizes the components of taxes other than income:
Year Ended December 31,Year Ended December 31,
(In millions)2016201520162015
Taxes other than income 
Production and severance$91
$131
$91
$131
Ad valorem23
39
23
39
Other54
64
37
46
Total$168
$234
Total taxes other than income$151
$216
General and administrative expensesdecreased $106107 million primarily due to cost savings realized from the 2015 workforce reductions including corresponding severance expenses.
Net interest and otherincreased $68$46 million primarily due to an increase in interest expense as a result of the increase in long-term debt in the second quarter of 2015. The components of net interest and other are detailed in Item 8. Financial Statements and Supplementary Data - Note 820 to the consolidated financial statements.
Provision (benefit) for income taxes reflects an effective tax rate of 73%79% and (25)%a benefit of 30% for 2016 and 2015. The increase ofin the 2016 effective tax rate was primarily due to the valuation allowance increase of $1,346 million related to our U.S. benefits on foreign taxes and other federal deferred tax assets.taxes.
See Item 8. Financial Statements and Supplementary Data - Note 97 to the consolidated financial statements for a discussion of the effective income tax rate.
Discontinued operations are presented net of tax. See Item 8. Financial Statements and Supplementary Data - Note 5 to the consolidated financial statements for financial information concerning our discontinued operations.
Segment Results: 2016 compared to 2015
Segment income(loss) for 2016
Segment income (loss) represents income (loss) from operations excluding certain items not allocated to segments, net of income taxes, attributable to the operating segments. A portion of our corporate and 2015 is summarizedoperations support general and reconciledadministrative costs are not allocated to the operating segments. Gains or losses on dispositions, certain impairments, unrealized gains or losses on commodity derivative instruments, pension settlement losses, or other items that affect comparability also are not allocated to operating segments
The following table reconciles segment income (loss) to net income (loss):
 Year Ended December 31,
(In millions)2016 2015
United States E&P$(415) $(452)
International E&P228
 112
Segment income (loss)(187) (340)
Items not allocated to segments, net of income taxes (a) 
(1,900) (1,361)
    Income (loss) from continuing operations(2,087) (1,701)
    Income (loss) from discontinued operations (b)
(53) (503)
         Net income (loss)$(2,140) $(2,204)
(a) See Item 8. Financial Statements and Supplementary Data - Note 6 to the consolidated financial statements for further detail about items not allocated to segments.
(b) We sold our Canadian business in the following table.second quarter of 2017. The Canadian business is reflected as discontinued operations in all periods presented.
 Year Ended December 31,
(In millions)2016 2015
North America E&P$(415) $(486)
International E&P228
 112
Oil Sands Mining(55) (113)
Segment income (loss)(242) (487)
Items not allocated to segments, net of income taxes(1,898) (1,717)
Net income (loss)$(2,140) $(2,204)
North America United States E&P segment lossdecreased $71$37 million in 2016 compared to 2015 as a result of lower net sales volumes and their impact to DD&A expense, production costs, and taxes other than income, which was nearly offset byand exploration expense, with these expense reductions more than offsetting the lower revenues as a result of decreases in both price realizations and net sales volumes. The remainder of the decrease was due to lower exploration expenses in 2016 relative to 2015.
 International E&P segment incomeincreased $116$116 million in 2016 compared to 2015. The increase was largely due to lower exploration expenses in 2016, as our 2015 expense included costs relating to our transition out of our conventional exploration program. The remainder of the increase was due to lower production costs and DD&A as a result of lower asset retirement costs and sales mix, and an increase in income from equity method investments, partially offset by lower price realizations.
 Oil Sands Mining segment loss decreased $58 million in 2016 compared to 2015 primarily due to higher sales volumes and lower production expenses, which were partially offset by lower price realizations.

Consolidated Results of Operations: 2015 compared to 2014
Sales and other operating revenues, including related partyare summarized by segment in the following table:
 Year Ended December 31,
(In millions)20152014
Sales and other operating revenues, including related party  
North America E&P$3,358
$5,770
International E&P728
1,410
Oil Sands Mining815
1,556
Segment sales and other operating revenues, including related party4,901
8,736
Unrealized gain on crude oil derivative instruments50

Sales and other operating revenues, including related party$4,951
$8,736
Below is a price/volume analysis for each segment. Refer to the preceding Operations and Market Conditions sections for additional detail related to our net sales volumes and average price realizations.
  Year Ended December 31, Increase (Decrease) Related to Year Ended December 31,
(In millions) 2014 Price Realizations Net Sales Volumes 2015
North America E&P Price-Volume Analysis
Liquid hydrocarbons $5,240
 $(3,006) $671
 $2,905
Natural gas 516
 (243) 68
 341
Realized gain on crude oil        
    derivative instruments 
 78
   78
Other sales 14
     34
Total $5,770
     $3,358
International E&P Price-Volume Analysis
Liquid hydrocarbons $1,240
 $(509) $(153) $578
Natural gas 124
 (8) (8) 108
Other sales 46
     42
Total $1,410
     $728
Oil Sands Mining Price-Volume Analysis
Synthetic crude oil $1,525
 $(842) $98
 $781
Other sales 31
     34
Total $1,556
     $815
Marketing revenues decreased $1,539 million in 2015 from 2014. Marketing activities include the purchase of commodities from third parties for resale and serve to aggregate volumes in order to satisfy transportation commitments as well as to achieve flexibility within product types and delivery points. Since the volume of marketing activity is based on market dynamics, it can fluctuate from period to period. The decreases are primarily related to the lower commodity price environment as well as lower marketed volumes in North America.
Income from equity method investments decreased $279 million primarily due to lower price realizations for LPG at our Alba Plant, LNG at our LNG facility and lower methanol prices at our AMPCO methanol facility, all of which are located in E.G. Also contributing to the decrease were lower sales volumes due to planned turnaround and maintenance activities at the AMPCO methanol plant, the Alba field and the LNG facility.
Net gain on disposal of assets in 2015 was related to the sale of our operated producing properties in the greater Ewing Bank area and non-operated producing interests in the Petronius field in the Gulf of Mexico. The gain associated with those assets was partially offset by the loss on sale of East Africa exploration acreage in Ethiopia and Kenya. The net loss on disposal of assets in 2014 was primarily related to the sale of non-core acreage located in the far northwest portion of the Williston Basin. See Item 8. Financial Statements and Supplementary Data - Note 6 to the consolidated financial statements for information about these dispositions.
Production expensesdecreased $552 million in 2015 from 2014. Our focus on cost discipline and efficiencies yielded sustainable savings in production costs. North America E&P declined $167 million due to lower operational, maintenance and labor costs. International E&P declined $131 million due to lower project work, repair, maintenance and turnaround costs, as

well as lower production volumes. OSM declined $254 million primarily due to cost management, especially staffing and contract labor, lower fuel and utility costs, and lower feedstock purchases given the increased mine and upgrader reliability, combined with a more favorable exchange rate on expenses denominated in the Canadian dollar.
The production expense rate (expense rate per boe) decreased for each of our segments as total production costs declined due to reasons described in the preceding paragraph. The North America E&P and OSM segments also experienced volume increases, which further contributed to the expense rate decline. The following table provides production expense rates for each segment:
($ per boe)20152014
North America E&P
$7.38

$10.25
International E&P
$5.99

$8.31
Oil Sands Mining (a)

$36.48

$44.53
(a)Production expense per synthetic crude oil barrel (before royalties) includes production costs, shipping and handling, taxes other than income and insurance costs and excludes pre-development costs.
Marketing expenses decreased $1,536 million in 2015 from the prior year, consistent with the decreases in marketing revenues discussed above.
Exploration expenses increased $525 million in 2015, primarily due to higher unproved property impairments in North America. During 2015, we made a strategic decision to reduce the overall level of our conventional exploration program; as a result, we impaired our Canadian in-situ assets, certain of our leases in the Gulf of Mexico and the Harir block in the Kurdistan Region of Iraq. We also impaired unproved property in Colorado in 2015, which we deemed uneconomic given our forecasted natural gas prices.
Unproved property impairments in 2014 primarily were a result of Eagle Ford and Bakken leases that either expired or we decided not to drill or extend.
Dry well costs for 2015 include the operated Solomon well in the Gulf of Mexico, our operated Sodalita West #1 exploratory well in E.G., and suspended well costs related to our Canadian in-situ assets at Birchwood. Dry well costs in 2014 also included our operated Sodalita West #1 exploratory well in E.G. which was drilling over year-end 2014, the operated Key Largo well, outside-operated Perseus well and the outside operated second Shenandoah appraisal well, all of which are located in the Gulf of Mexico. In addition, 2014 also includes our exploration programs in the Kurdistan Region of Iraq, Ethiopia and Kenya.
The following table summarizes the components of exploration expenses:
 Year Ended December 31,
(In millions)20152014
Unproved property impairments$964
$306
Dry well costs250
317
Geological and geophysical31
85
Other73
85
Total exploration expenses$1,318
$793
Exploration expense are also discussed in Item 8. Financial Statements and Supplementary Data - Note 13 to the consolidated financial statements.
Depreciation, depletion and amortization increased $96 million in 2015 from the prior year primarily as a result of higher North America E&P net sales volumes from our three U.S. resource plays. Our segments apply the units-of-production method to the majority of their assets, including capitalized asset retirement costs; therefore, proved reserve and production volumes have an impact on DD&A expense.
The DD&A rate (expense rate per boe), which is impacted by changes in proved reserves, capitalized costs and sales volume mix by field, can also cause changes to our DD&A. The following table provides DD&A rates for each segment. The DD&A rate for North America E&P decreased primarily as a result of a higher proved reserve base in the Eagle Ford. The International E&P rate increased primarily due to higher sales volumes from the Brae infill drilling program.
($ per boe)20152014
North America E&P
$24.24

$26.95
International E&P
$6.95

$5.79
Oil Sands Mining
$12.48

$12.07

Impairments for 2015 included $340 million for the goodwill impairment of the North America E&P reporting unit, $335 million related to proved properties (primarily in Colorado and the Gulf of Mexico) as a result of lower forecasted commodity prices and $44 million associated with our disposition of natural gas assets in East Texas, North Louisiana and Wilburton, Oklahoma. Impairments for 2014 consisted primarily of proved properties in the Gulf of Mexico, Texas and North Dakota as a result of revisions to estimated abandonment costs and lower forecasted commodity prices. See Item 8. Financial Statements and Supplementary Data - Note 13 and Note 14 to the consolidated financial statement for additional detail. 
Taxes other than incomeinclude production, severance and ad valorem taxes, primarily in the U.S., which tend to increase or decrease in relation to revenues and sales volumes. With the decrease in North America E&P revenues due to lower price realizations, taxes other than income decreased $172 million in 2015. This decrease was partially offset by an increase in sales volumes in North America E&P. The following table summarizes the components of taxes other than income:
 Year Ended December 31,
(In millions)20152014
Production and severance$131
$240
Ad valorem39
74
Other64
92
Total$234
$406
General and administrative expenses decreased $64 million primarily due to cost savings realized from the workforce reductions that occurred during 2015. This decrease was partially offset by severance expenses of $55 million associated with the workforce reductions and an increase in pension settlement expense. Pension settlement expenses in 2015 totaled $119 million as compared to $99 million in 2014.
Net interest and other increased $29 million primarily due to increased interest expense associated with an increase in long-term debt. The components of net interest and other are detailed in Item 8. Financial Statements and Supplementary Data - Note 8 to the consolidated financial statements.
Provision (benefit) for income taxesreflects an effective tax rate of (25)% and 29% for each of 2015 and 2014. See Item 8. Financial Statements and Supplementary Data - Note 9 to the consolidated financial statements for a discussion of the effective income tax rate.
Discontinued operations is presented net of tax. We closed the sale of our Angola assets and Norway business in 2014, and both are reflected as discontinued operations for 2014. Included in the discontinued operations for 2014 are after-tax gains of $532 million and $976 million related to the dispositions of Angola and Norway respectively. See Item 8. Financial Statements and Supplementary Data – Note 6 to the consolidated financial statements.
Segment Results: 2015 compared to 2014
Segment income (loss) for 2015 and 2014 is summarized and reconciled to net income (loss) in the following table.
 Year Ended December 31,
(In millions)2015 2014
North America E&P$(486) $693
International E&P112
 568
Oil Sands Mining(113) 235
Segment income (loss)(487) 1,496
Items not allocated to segments, net of income taxes$(1,717) (527)
    Income (loss) from continuing operations(2,204) 969
    Discontinued operations
 2,077
         Net income (loss)$(2,204) $3,046
 North America E&P segment income (loss) decreased $1,179 million in 2015 compared to 2014. The decrease was primarily due to lower price realizations, which was partially offset by the impacts from the increased net sales volumes from the three U.S resource plays and lower production costs (even though net sales volumes increased).
International E&P segment income decreased $456 million in 2015 compared to 2014. The decrease was largely due to lower liquid hydrocarbon price realizations as well as reduced income from equity investments. These declines were partially offset by lower production, operating and exploration expenses.
Oil Sands Mining segment income (loss) decreased $348 million in 2015 compared to 2014 primarily as result of lower price realizations, partially offset by higher sales volumes and reduced production expenses.

Management’s Discussion and Analysis of Financial Condition, Cash Flows and Liquidity
Commodity prices are the most significant factor impacting our operating cash flows and the amount of capital available to reinvest into the business. In 2016,2017, we experienced an increase in operating cash flows primarily due to improvements in the commodity price environment which resulted in an increase to consolidated average liquid hydrocarbons price realizations by over 30% to $42.59. Additionally, we closed on the sale of certainour Canadian business and other non-core assets resulting in net proceeds of $1.2$1.79 billion, including closing adjustments, which allowed us to be opportunistic with aour high quality acquisitionacquisitions in Oklahoma's STACK play. Our successful portfolio management allowed us to realize our goal of living within cash flows in 2016.the Permian basin. Beyond the proceeds the non-core asset sales generated, the portfolio changes enhanceenhanced our profitability by driving outdisposing of higher unit cost operations and allowing for thea more efficient allocation of our Capital Development Program to the highhigher return opportunities in the U.S. resource plays. We plan to continue the progress we made in 2016 towards achieving profitable growth within cash flows as the price environment improves.
Steps taken in 2017 to respond to the sustained low commodity prices during 2016 includedcontinue our operating cash flow growth include the following strategic actions:
Improved cost structure by reducing production expense per boe in 2017.
United States E&P - 7% reduction to $5.57 per boe
International E&P - 14% reduction to $4.33 per boe
Total 2017 net sales volumes from continuing operations increased 10% compared to 2016.
Other 2017 cash flow highlights include:
Divested of certain non-core assets resulting in net proceeds of $1.2$1.79 billion.
We closed on multiple Permian basin acquisitions for $1.89 billion
with cash on hand.
RaisedThrough multiple financing transactions we have reduced total debt by approximately $1.75 billion which will result in a reduction to our future annual interest expense of approximately $115 million.
Expect to receive $750 million in remaining proceeds from the sale of $1.2 billion from an equity offering in the first quarter of 2016
Reduced cash additions to property, plant and equipment to $1.2 billion, a 64% decrease compared to 2015our Canadian business by March 1, 2018.
Expanded the capacity of the revolving credit facility from $3.0$3.3 billion to $3.3 billion in the first quarter of 2016
Improved cost structure by reducing total company production expenses by 23% and production expense per boe in 2016 by:
North America E&P - 19% reduction to $5.96 per boe
International E&P - 16% reduction to $5.05 per boe
Oil Sands Mining - 24% reduction to $27.89 per boe
Increased cash and cash equivalents by $1.3 billion from year-end 2015
Progressed our 2017 commodity hedging program which covers approximately 40% of our expected U.S. crude oil and natural gas production. Pricing for these hedges is discussed in further detail in Item 8. Financial Statements and Supplementary Data – Note 16 to the consolidated financial statements$3.4 billion.
At December 31, 2016,2017, we had approximately $5.8$4.0 billion of liquidity consisting of $2.5 billion$563 million in cash and cash equivalents and $3.3$3.4 billion available under our revolving credit facility. As previously discussed in our Outlook section, we are targeting a $2.2$2.3 billion Capital Development Program for 2017.2018. We believe our current liquidity level and balance sheet, along with our non-core asset disposition program and ability to access the capital markets provides us with the flexibility to fund our business throughout the sustained lowerdifferent commodity price cycle.cycles. We will continue to evaluate the commodity price environment and our spending throughout 2017.2018.

Cash Flows
The following table presents sources and uses of cash and cash equivalents from continuing operations for 2017, 2016 2015 and 2014:2015:
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Sources of cash and cash equivalents 
  
   
  
  
Continuing operations$1,073
 $1,565
 $4,736
Discontinued operations
 
 751
Disposals of assets1,219
 225
 3,760
Issuance of common stock1,236
 
 
Maturities of short-term investment
 925
 
Borrowings, net
 1,996
 
Operating activities - continuing operations$1,988
 $901
 $1,537
Disposals of assets, net of cash transferred to the buyer1,787
 1,219
 225
Common stock issuance
 1,236
 
Borrowings988
 
 1,996
Other56
 91
 214
68
 56
 101
Total sources of cash and cash equivalents$3,584
 $4,802
 $9,461
$4,831
 $3,412
 $3,859
Uses of cash and cash equivalents          
Cash additions to property, plant and equipment$(1,245) $(3,476) $(5,160)$(1,974) $(1,204) $(3,485)
Purchases of short-term investments
 (925) 
Investing activities of discontinued operations
 
 (376)
Acquisitions(902) 
 (21)
Acquisitions, net of cash acquired(1,891) (902) 
Purchases of common stock
 
 (1,000)(11) (6) (11)
Commercial paper, net
 
 (135)
Debt repayments(1) (1,069) (68)(2,764) (1) (1,069)
Debt issuance costs
 (19) 
Debt extinguishment costs(46) 
 
Dividends paid(162) (460) (543)(170) (162) (460)
Other(5) (30) (24)(30) (4) (8)
Total uses of cash and cash equivalents$(2,315) $(5,979) $(7,327)$(6,886) $(2,279) $(5,033)
Cash flows generated from continuing operationsoperating activities in 20162017 were lower than 2015higher as the downturn in commodity prices continued to impactand price realizations improved compared to 2016. This increase in price realization coupled with lower netour increased sales volumes which negatively impact ourand continued focus on cost reductions resulted in an increase to cash flows generated from operating activities. In 2016,
Proceeds from the disposals of assets for 2017 are primarily a result of the disposal of our weighted average crude oilCanadian business, and natural gas price realizations were down 11% and 16% as compared to the prior year.
Proceedsproceeds from disposals of assets in 2016 are primarily from the sale of our Wyoming upstream and midstream assets, as well as the sale of certain other non-operated CO2 and waterflood assets in West Texas and New Mexico. Disposals of assets in 2015 pertain to the sale of certain of our operated and non-operated producing properties in the Gulf of Mexico as well as natural gas assets in East Texas, North Louisiana and Wilburton, Oklahoma. Disposals in 2014 primarily reflect the proceeds from the sales of our Angola assets and our Norway business. Disposition transactions are discussed in further detail in Item 8. Financial Statements and Supplementary Data – Note 65 to the consolidated financial statements.
Issuance of common stock reflects net proceeds received in March 2016.2016 from our public sale of common stock. See Item 8. Financial Statements and Supplementary Data - Note 2322 to the consolidated financial statements for additional information.
Cash flows from discontinued operations primarily related to our Norway business, which we disposedBorrowings in 2017 are a result of the issuance of $1 billion of 4.4% senior unsecured notes due in fourth quarter 2014.
Borrowings2027. Our 2015 borrowings reflect net proceeds received from the issuance of senior notes in June 2015. In November 2015, we repaid our $1 billion 0.90% senior notes upon maturity.
We announced an adjustment to our quarterly dividend startingFinancing transactions are discussed in third quarter 2015, with the full-year impact resultingfurther detail in a decrease of dividends paid in the current year.
During the third quarter of 2016, we closed the Oklahoma STACK acquisition for a purchase price of $902 million, net of cash acquired; see Item 8. Financial Statements and Supplementary Data – Note 515 to the consolidated financial statements for further information concerning acquisitions.

additional information.
Additions to property, plant and equipment are our mostreflect a significant use of cash and cash equivalents. The following table shows capital expenditures related to continuing operations by segment and reconciles to additions to property, plant and equipment as presented in the consolidated statements of cash flows for 2017, 2016 2015 and 2014:2015:
 Year Ended December 31,
(In millions)2016 2015 2014
North America E&P$936
 $2,553
 $4,698
International E&P82
 368
 534
Oil Sands Mining (a)
33
 (10) 212
Corporate18
 25
 51
Total capital expenditures1,069
 2,936
 5,495
Change in capital expenditure accrual176
 540
 (335)
Additions to property, plant and equipment$1,245
 $3,476
 $5,160
(a) Reflects reimbursements earned from
 Year Ended December 31,
(In millions)2017 2016 2015
United States E&P$2,081
 $936
 $2,553
International E&P42
 82
 368
Corporate27
 18
 25
Total capital expenditures2,150
 1,036
 2,946
Change in capital expenditure accrual(176) 168
 539
Additions to property, plant and equipment$1,974
 $1,204
 $3,485
During 2017, we closed on multiple Permian basin acquisitions for approximately $1.9 billion with cash on hand. Additionally, during 2016, we closed the governmentsOklahoma STACK acquisition for a purchase price of Canada and Alberta related to funds previously expended for Quest CCS capital equipment. Quest CCS was successfully completed and commissioned in the fourth quarter$902 million, net of 2015.cash
There were no share repurchases in 2016 or 2015. During 2014, we acquired 29 million shares at a cost of $1 billion. See
acquired; see Item 8. Financial Statements and Supplementary Data – Note 234 to the consolidated financial statements for discussionfurther information concerning acquisitions.
In December 2017, we redeemed $1 billion of purchases5.125% municipal revenue bonds due in 2037 in a refunding transaction. Additionally, during the third quarter of common stock.2017, we used the net proceeds of the borrowing disclosed above plus existing cash on hand to redeem $1.76 billion in senior unsecured notes resulting in a recognized loss on early extinguishment of debt of $46 million, primarily due to make-whole call provisions. In November 2015, we repaid our $1 billion 0.90% senior notes upon maturity. Financing transactions are discussed in further detail in Item 8. Financial Statements and Supplementary Data – Note 15 to the consolidated financial statements for additional information.
During 2017, the Board of Directors approved a $0.05 per share quarterly dividend. See Capital Requirements below for additional information about the fourth quarter dividend. During 2015 we announced an adjustment to our quarterly dividend starting in third quarter 2015, with the full-year impact resulting in a decrease of dividends paid in 2017 and 2016.
Liquidity and Capital Resources
In March 2016,June 2017, we issued 166,750,000 sharesextended the maturity date of our common stock, par value $1 per share, at a price of $7.65 per share, excluding underwriting discounts and commissions, for net proceeds of $1,236 million. The proceeds were usedCredit Facility from May 28, 2020, to strengthen our balance sheet and for general corporate purposes, including funding a portion of our Capital Program.
Also in March 2016,May 28, 2021. In July 2017, we increased our $3$3.3 billion unsecured revolving credit facilityCredit Facility by $300$93 million to a total of $3.3$3.4 billion. Fees on the unused commitment of each lender, as well as the borrowing options under the revolving credit facility,Credit Facility, remain unaffected by the increase.increase and term extension. We have the ability to request two additional one-year extensions and an option to increase the commitment amount by up to an additional $107 million, subject to the consent of any increasing lenders.  The sub-facilities for swing-line loans and letters of credit remain unchanged allowing up to an aggregate amount of $100 million and $500 million, respectively.
Our main sources of liquidity are cash and cash equivalents, internally generated cash flow from operations, sales of non-core assets, capital market transactions, and our $3.3 billion revolving credit facility. At December 31, 2016,2017, we had approximately $5.8$4.0 billion of liquidity consisting of $2.5 billion$563 million in cash and cash equivalents and $3.3$3.4 billion available under our revolving credit facility. During the first quarter of 2018, we expect to receive $750 million in remaining proceeds from the sale of our Canadian business. Our working capital requirements are supported by these sources and we may draw on our $3.3 billion revolving credit facility to meet short-term cash requirements, or issue debt or equity securities through the shelf registration statement discussed below as part of our longer-term liquidity and capital management.management program. Because of the alternatives available to us as discussed above, we believe that our short-term and long-term liquidity are adequate to fund not only our current operations, but also our near-term and long-term funding requirements including our capital spending programs, dividend payments, defined benefit plan contributions, repayment of debt maturities, and other amounts that may ultimately be paid in connection with contingencies.
DueGeneral economic conditions, commodity prices, and financial, business and other factors could affect our operations and our ability to decreases in crude oil and U.S. natural gas prices, credit rating agencies reviewed companies inaccess the industry earlier this year. During the first quarter of 2016, ourcapital markets. Our corporate credit rating was downgraded by:ratings as of December 31, 2017 are: Standard & Poor's Ratings Services to BBB- (stable) from; Fitch Ratings BBB (stable); by Fitch Ratings to BBB (negative) from BBB+ (stable); and by Moody's Investor Services, Inc. to Ba1 (negative) from Baa1 (stable). On October 11, 2016, Moody’s Investor Services, Inc. subsequently revised their outlook ofA downgrade in our corporate credit rating to stable from negative. Any further rating downgradesratings could increase our future cost of financing or limit our ability to access capital, and result in additional collateral requirements. See Item 1A. Risk Factors for a discussion of how a further downgrade in our credit ratings could affect us.
In December of 2017, we redeemed $1 billion of 5.125% municipal revenue bonds due in 2037 in a refunding transaction that preserved our ability to remarket up to $1 billion of tax-exempt municipal bonds prior to 2037. We may incur additional debt in order to fund our capital expenditures, acquisitions or development activities, or for general corporate or other purposes. A higher level of indebtedness could increase the risk that our liquidity and financial flexibility deteriorates. See Item 1A. Risk Factors for a further discussion of how our level of indebtedness could affect us.
The June 23, 2016 referendum by British voters to exit the European Union (“Brexit”) provided volatility around European currencies and resulted in a decline in the value of the British pound, as compared to the U.S. dollar and other currencies. For our U.K. operations, a majority of our revenues are tied to global crude oil prices which are denominated in U.S. dollars while a significant portion of our operating and capital costs are denominated in British pounds. In addition, our U.K. operations have an asset retirement obligation, which represents a future cash commitment. In the longer term, any impact from Brexit on our U.K. operations will depend, in part, on the outcome of tariff, trade, regulatory, and other negotiations.



Capital Resources
Credit Arrangements and Borrowings
At December 31, 2016,2017, we had no borrowings against our revolving credit facility.
At December 31, 2016,2017, we had $7.3$5.5 billion in long-term debt outstanding, with our next debt maturity in the amount of $682$600 million due in the fourth quarter of 2017.2020.
We do not have any triggers on any of our corporate debt that would cause an event of default in the case of a downgrade of our credit ratings.
Shelf Registration
We have a universal shelf registration statement filed with the SEC under which we, as a "well-known seasoned issuer" for purposes of SEC rules, have the ability to issue and sell an indeterminate amount of various types of debt and equity securities.

Asset Disposals
We have closed or announced $1.3on $1.8 billion of non-core asset sales during 2016. In2017, with the largest transaction we announcedbeing the saledisposal of our Wyoming upstream and midstream assets and received proceedsCanadian business. During the third quarter of approximately $845 million. We also entered into multiple agreements to sell certain non-operated assets, and CO2 and waterflood assets in West Texas and New Mexico for combined proceeds of approximately $302 million. Additionally,2017, we entered into separate agreements to sell certain non-core properties in our 10% working interest in the outside-operated Shenandoah discovery in the GulfInternational E&P segment for combined proceeds of Mexico, operated natural gas assets in the Piceance basin in Colorado and certain undeveloped acreage in West Texas for a combined total of approximately $80$53 million, in proceeds.before closing adjustments. We have closed on certainone of these asset salesagreements in 2016, with2017, and we expect the remaining asset sales expectedremainder of the agreements to close in the second quarter of 2017.during 2018.
See Item 8. Financial Statements and Supplementary Data – Note 65 to the consolidated financial statements for additional discussion of these dispositions.    
Cash-Adjusted Debt-To-Capital Ratio
The Credit Facility includes a covenant requiring that our ratio of total debt to total capitalization not exceed 65% as of the last day of each fiscal quarter. Our cash-adjusted debt-to-capital ratio (total debt-minus-cash to total debt-plus-equity-minus-cash) was 21%32% at December 31, 20162017 and 25%29% at December 31, 2015.2016.
(Dollars in millions)2016 20152017 2016
Long-term debt due within one year$686
 $1
$
 $686
Long-term debt6,589
 7,276
5,494
 6,581
Total debt$7,275
 $7,277
$5,494
 $7,267
Cash and cash equivalents$2,490
 $1,221
Equity$17,541
 $18,553
$11,708
 $17,541
Calculation      
Total debt$7,275
 $7,277
$5,494
 $7,267
Minus cash and cash equivalents2,490
 1,221
Total debt minus cash and cash equivalents4,785

6,056
Total debt$7,275
 $7,277
Plus equity17,541
 18,553
Minus cash and cash equivalents2,490
 1,221
Total debt plus equity minus cash, cash equivalents$22,326

$24,609
Cash-adjusted debt-to-capital ratio21% 25%
Total debt plus equity (total capitalization)$17,202

$24,808
Debt-to-capital ratio32% 29%
Capital Requirements
Capital Spending
Our approved Capital Development Program for 20172018 is $2.2$2.3 billion. Additional details were previously discussed in Outlook.
Share Repurchase Program
The remaining share repurchase authorization as of December 31, 20162017 is $1.5 billion.




Other Expected Cash Outflows
On January 25, 2017,30, 2018, our Board of Directors approved a dividend of $0.05 per share for the fourth quarter of 2016.2017. The dividend is payable on March 10, 201712, 2018 to shareholders on record on February 15, 2017.21, 2018.
We plan to make contributions of up to $60$65 million to our funded pension plans during 2017.2018. Cash contributions to be paid from our general assets for the unfunded pension and postretirement plans are expected to be approximately $5$6 million and $21 million in 2017.2018.

Contractual Cash Obligations
The table below provides aggregated information on our consolidated obligations to make future payments under existing contracts as of December 31, 2016.2017.
(In millions)Total 2017 
2018-
2019
 
2020-
2021
 
Later
Years
Total 2018 
2019-
2020
 
2021-
2022
 
Later
Years
Short and long-term debt (includes interest)(a)
$11,318
 $1,042
 $1,654
 $1,102
 $7,520
$8,776
 $256
 $1,103
 $1,512
 $5,905
Lease obligations183
 36
 58
 55
 34
119
 29
 55
 31
 4
Purchase obligations:                  
Oil and gas activities(b)
151
 128
 14
 7
 2
108
 94
 8
 4
 2
Service and materials contracts(c)
764
 78
 93
 28
 565
115
 65
 48
 2
 
Transportation and related contracts1,606
 256
 483
 261
 606
1,581
 313
 483
 241
 544
Drilling rigs and fracturing crews(d)
44
 44
 
 
 
21
 21
 
 
 
Other126
 20
 32
 22
 52
42
 13
 24
 5
 
Total purchase obligations2,691
 526
 622
 318
 1,225
1,867
 506
 563
 252
 546
Other long-term liabilities reported in the consolidated balance sheet(e)
370
 51
 69
 69
 181
486
 141
 77
 63
 205
Total contractual cash obligations(f)
$14,562
 $1,655
 $2,403
 $1,544
 $8,960
$11,248
 $932
 $1,798
 $1,858
 $6,660
(a) 
Includes anticipated cash payments for interest of $359$256 million for 2017, $5722018, $503 million for 2018-2019, $5022019-2020, $477 million for 2020-20212021-2022 and $2,585$2,003 million for the remaining years for a total of $4,018$3,239 million.
(b) 
Oil and gas activities include contracts to acquire property, plant and equipment and commitments for oil and gas exploration such as costs related to contractually obligated exploratory work programs that are expensed immediately.
(c) 
Service and materials contracts include contracts to purchase services such as utilities, supplies and various other maintenance and operating services.
(d) 
Some contracts may be canceled at an amount less than the contract amount. Were we to elect that option where possible at December 31, 20162017 our minimum commitment would be $42$14 million.
(e) 
Primarily includes obligations for pension and other postretirement benefits including medical and life insurance. We have estimated projected funding requirements through 2026.2027. Although unrecognized tax benefits are not a contractual obligation, they are presented in this table because they represent potential demands on our liquidity.
(f) 
This table does not include the estimated discounted liability for dismantlement, abandonment and restoration costs of oil and gas properties of $1,748$1,483 million. See Item 8. Financial Statements and Supplementary Data – Note 1811 to the consolidated financial statements.

Transactions with Related Parties
We own a 63% working interest in the Alba field offshore E.G. Onshore E.G., we own a 52% interest in an LPG processing plant, a 60% interest in an LNG production facility and a 45% interest in a methanol production plant, each through equity method investees. We sell our natural gas from the Alba field to these equity method investees as the feedstock for their production processes.
Off-Balance Sheet Arrangements
Off-balance sheet arrangements comprise those arrangements that may potentially impact our liquidity, capital resources and results of operations, even though such arrangements are not recorded as liabilities under accounting principles generally accepted in the U.S. Although off-balance sheet arrangements serve a variety of our business purposes, we are not dependent on these arrangements to maintain our liquidity and capital resources, and we are not aware of any circumstances that are reasonably likely to cause the off-balance sheet arrangements to have a material adverse effect on liquidity and capital resources.
We will issue stand-alone letters of credit when required by a business partner. Such letters of credit outstanding at December 31, 2017, 2016 and 2015 and 2014 aggregated $89 million, $166 million $53 million and $101$53 million. Most of the letters of credit are in support of obligations recorded in the consolidated balance sheet. For example, they are issued to counterparties to insure our payments for outstanding company debtsupport firm transportation agreements and future abandonment liabilities.

Management’s Discussion and Analysis of Environmental Matters, Litigation and Contingencies
We have incurred and may continue to incur substantial capital, operating and maintenance and remediation expenditures as a result of environmental laws and regulations. If these expenditures, as with all costs, are not ultimately reflected in the prices of our products and services, our operating results will be adversely affected. We believe that substantially all of our competitors must comply with similar environmental laws and regulations. However, the specific impact on each competitor may vary depending on a number of factors, including the age and location of its operating facilities, marketing areas and production processes.
Legislation and regulations pertaining to climate change and greenhouse gas emissions have the potential to materially adversely impact our business, financial condition, results of operations and cash flows, including costs of compliance and permitting delays. The extent and magnitude of these adverse impacts cannot be reliably or accurately estimated at this time because specific regulatory and legislative requirements have not been finalized and uncertainty exists with respect to the measures being considered, the costs and the time frames for compliance, and our ability to pass compliance costs on to our customers. For additional information see Item 1A. Risk Factors.
We accrue for environmental remediation activities when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. As environmental remediation matters proceed toward ultimate resolution or as additional remediation obligations arise, charges in excess of those previously accrued may be required.
New or expanded environmental requirements, which could increase our environmental costs, may arise in the future. We strive to comply with all legal requirements regarding the environment, but as not all costs are fixed or presently determinable (even under existing legislation) and may be affected by future legislation or regulations, it is not possible to predict all of the ultimate costs of compliance, including remediation costs that may be incurred and penalties that may be imposed.
For more information on environmental regulations that impact us, or could impact us, see Item 1. Business – Environmental, Health and Safety Matters, Item 1A. Risk Factors and Item 3. Legal Proceedings.
Critical Accounting Estimates
The preparation of financial statements in accordance with accounting principles generally accepted in the U.S. requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods. Accounting estimates are considered to be critical if (1) the nature of the estimates and assumptions is material due to the levels of subjectivity and judgment necessary to account for highly uncertain matters or the susceptibility of such matters to change, and (2) the impact of the estimates and assumptions on financial condition or operating performance is material. Actual results could differ from the estimates and assumptions used.
Estimated Quantities of Net Reserves
We use the successful efforts method of accounting for our oil and gas producing activities. The successful efforts method inherently relies on the estimation of proved crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves. The amount of estimated proved reserve volumes affect, among other things, whether certain costs are capitalized or expensed, the amount and timing of costs depreciated, depleted or amortized into net income and the presentation of supplemental information on oil and gas producing activities. In addition, the expected future cash flows to be generated by producing properties are used for testing impairment and the expected future taxable income available to realize deferred tax assets, also in part, rely on estimates of quantities of net reserves. Refer to the applicable sections below for further discussion of these accounting estimates.

The estimation of quantities of net reserves is a highly technical process performed by our engineers and geoscientists for crude oil and condensate, NGLs and natural gas, and synthetic crude oil, which is based upon several underlying assumptions. The reserve estimates may change as additional information becomes available and as contractual, operational, economic and political conditions change. We evaluate our reserves using drilling results, reservoir performance, seismic interpretation and future plans to develop acreage. Technologies used in proved reserves estimation includes statistical analysis of production performance, decline curve analysis, pressure and rate transient analysis, pressure gradient analysis, reservoir simulation and volumetric analysis. The observed statistical nature of production performance coupled with highly certain reservoir continuity or quality within the reliable technology areas and sufficient proved developed locations establish the reasonable certainty criteria required for booking proved reserves. The data for a given reservoir may also change over time as a result of numerous factors including, but not limited to, additional development activity, production history and continual reassessment of the viability of production under varying economic conditions.


Reserve estimates are based on an unweighted arithmetic average of commodity prices during the 12-month period, using the closing prices on the first day of each month, as defined by the SEC. The table below provides the 20162017 SEC pricing for certain benchmark prices:
SEC Pricing 2016SEC Pricing 2017
WTI Crude oil (per bbl)
$42.75
$51.34
Henry Hub natural gas (per mmbtu)
$2.49
$2.98
Brent crude oil (per bbl)
$43.53
$54.39
Mont Belvieu NGLs (per bbl)
$15.89
$22.03
When determining the December 31, 20162017 proved reserves for each property, the benchmark prices listed above were adjusted using price differentials that account for property-specific quality and location differences.
Estimates of future cash flows associated with proved reserves are based on actual costs of developing and producing proved reserves at the end of the year. If commodity prices were to significantly dropdecrease by approximately 10%, below average prices used to estimate 20162017 proved reserves (see table above), we would not expect price related reserve revisions that couldto have a material impact on proved reserve volumes and the present value of our proved reserves. In this scenario, our OSM proved reserves represent the largest risk to be reclassified to non-proved reserves or resource category.volumes. For further discussion of risks associated with our estimation of proved reserves, see Part I. Item 1A Risk Factors.
Depreciation and depletion of crude oil and condensate, NGLs and natural gas and synthetic crude oil producing properties is determined by the units-of-production method and could change with revisions to estimated proved reserves. While revisions of previous reserve estimates have not historically been significant to the depreciation and depletion rates of our segments, any reduction in proved reserves, could result in an acceleration of future DD&A expense. The following table illustrates, on average, the sensitivity of each segment's units-of-production DD&A per boe and pretax income to a hypothetical 10% change in 20162017 proved reserves based on 20162017 production.
Impact of a 10% Increase in Proved Reserves Impact of a 10% Decrease in Proved ReservesImpact of a 10% Increase in Proved Reserves Impact of a 10% Decrease in Proved Reserves
(In millions, except per boe)DD&A per boe Pretax Income DD&A per boe Pretax IncomeDD&A per boe Pretax Income DD&A per boe Pretax Income
North America E&P$(2.04) $167
 $2.50
 $(204)
United States E&P$(2.14) $183
 $2.61
 $(224)
International E&P$(0.56) $25
 $0.69
 $(31)$(0.56) $30
 $0.69
 $(36)
Oil Sands Mining$(0.99) $18
 $1.26
 $(22)
Asset Retirement Obligations
We have material legal, regulatory and contractual obligations to remove and dismantle long-lived assets and to restore land or seabed at the end of oil and gas production operations, including bitumen mining operations. A liability equal to the fair value of such obligations and a corresponding capitalized asset retirement cost are recognized on the balance sheet in the period in which the legal obligation is incurred and a reasonable estimate of fair value can be made. The capitalized asset retirement cost is depreciated using the units-of-production method or the straight line method (dependent on the underlying asset) and the discounted liability is accreted over the period until the obligation is satisfied, the impacts of which are recognized as DD&A in the consolidated statements of income. In many cases, the satisfaction and subsequent discharge of these liabilities is projected to occur many years, or even decades, into the future. Furthermore, the legal, regulatory and contractual requirements often do not provide specific guidance regarding removal practices and the criteria that must be fulfilled when the removal and/or restoration event actually occurs.
Estimates of retirement costs are developed for each property based on numerous factors, such as the scope of the dismantlement, timing of settlement, interpretation of legal, regulatory and contractual requirements, type of production and processing structures, depth of water (if applicable), reservoir characteristics, depth of the reservoir, market demand for equipment, currently available dismantlement and restoration procedures and consultations with construction and engineering professionals. Inflation rates and credit-adjusted-risk-free interest rates are then applied to estimate the fair values of the obligations. To the extent these or other assumptions change after initial recognition of the liability, the fair value estimate is revised and the recognized liability adjusted, with a corresponding adjustment made to the related asset balance or income statement, as appropriate. Changes in estimated asset retirement obligations for late life assets could result in future impairment charges.charges or in the recognition of income. See Item 8. Financial Statements and Supplementary Data – Note 1811 to the consolidated financial statements for disclosures regarding our asset retirement obligation estimates.
An estimate of the sensitivity to net income if other assumptions had been used in recording these liabilities is not practical because of the number of obligations that must be assessed, the number of underlying assumptions and the wide range of possible assumptions.

Fair Value Estimates
Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There are three approaches for measuring the fair value of assets and liabilities: the market approach, the income approach and the cost approach, each of which includes multiple valuation techniques. The market approach uses prices and other relevant information generated by market transactions involving identical or comparable assets or liabilities. The income approach uses valuation techniques to measure fair value by converting future amounts, such as cash flows or earnings, into a single present value, or range of present values, using current market expectations about those future amounts. The cost approach is based on the amount that would currently be required to replace the service capacity of an asset. This is often referred to as current replacement cost. The cost approach assumes that the fair value would not exceed what it would cost a market participant to acquire or construct a substitute asset of comparable utility, adjusted for obsolescence.
The fair value accounting standards do not prescribe which valuation technique should be used when measuring fair value and do not prioritize among the techniques. These standards establish a fair value hierarchy that prioritizes the inputs used in applying the various valuation techniques. Inputs broadly refer to the assumptions that market participants use to make pricing decisions, including assumptions about risk. Level 1 inputs are given the highest priority in the fair value hierarchy while Level 3 inputs are given the lowest priority. The three levels of the fair value hierarchy are as follows:
Level 1 – Observable inputs that reflect unadjusted quoted prices for identical assets or liabilities in active markets as of the measurement date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.
Level 2 – Observable market-based inputs or unobservable inputs that are corroborated by market data. These are inputs other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the measurement date.
Level 3 – Unobservable inputs that are not corroborated by market data and may be used with internally developed methodologies that result in management’s best estimate of fair value.
Valuation techniques that maximize the use of observable inputs are favored. Assets and liabilities are classified in their entirety based on the lowest priority level of input that is significant to the fair value measurement. The assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the placement of assets and liabilities within the levels of the fair value hierarchy. See Item 8. Financial Statements and Supplementary Data – Note 1514 to the consolidated financial statements for disclosures regarding our fair value measurements.
Significant uses of fair value measurements include:
impairment assessments of long-lived assets;
impairment assessments of goodwill; and
recorded value of derivative instruments.
The need to test long-lived assets and goodwill for impairment can be based on several indicators, including a significant reduction in prices of crude oil and condensate, NGLs and natural gas, or synthetic crude oil, sustained declines in our common stock, reductions to our Capital Development Program, unfavorable adjustments to reserves, significant changes in the expected timing of production, other changes to contracts or changes in the regulatory environment in which the property is located.
Impairment Assessments of Long-Lived Assets
Long-lived assets in use are assessed for impairment whenever changes in facts and circumstances indicate that the carrying value of the assets may not be recoverable. For purposes of an impairment evaluation, long-lived assets must be grouped at the lowest level for which independent cash flows can be identified, which generally is field-by-field or, in certain instances, by logical grouping of assets if there is significant shared infrastructure or contractual terms that cause economic interdependency amongst separate, discrete fields. If the sum of the undiscounted estimated cash flows from the use of the asset group and its eventual disposition is less than the carrying value of an asset group, the carrying value is written down to the estimated fair value. During 2016 the sustained decline of2017 lower forecasted long-term commodity prices resultedand the anticipated sales of certain non-core proved properties in a downward revisions of our long-term commodity price assumptions whichInternational E&P segment triggered an assessment of certain of our long-lived assets related to oil and gas producing properties for impairment. We estimated the fair values using an income and market approach and recognized impairments. As of the date of our last impairment assessment,December 31, 2017 our estimated undiscounted cash flows relating to our remaining long-lived assets significantly exceeded their carrying values. Long-lived assets most at risk for future impairment (defined as those assets with estimated undiscounted cash flows that exceeded their carrying values by less than approximately 50%) had estimated undiscounted cash flows that exceeded their $269$66 million carrying value by $139$22 million. See Item 8. Financial Statements and Supplementary Data Note 1310 and Note 1514 to the consolidated financial statements for discussion of impairments recorded in 2017, 2016 2015 and 20142015 and the related fair value measurements.

Fair value calculated for the purpose of testing our long-lived assets for impairment is estimated using the present value of expected future cash flows method and comparative market prices when appropriate. Significant judgment is involved in performing these fair value estimates since the results are based on forecasted assumptions. Significant assumptions include:
Future crude oil and condensate, NGLs and natural gas and synthetic crude oil prices. Our estimates of future prices are based on our analysis of market supply and demand and consideration of market price indicators. Although these commodity prices may experience extreme volatility in any given year, we believe long-term industry prices are driven by global market supply and demand. To estimate supply, we consider numerous factors, including the worldwide resource base, depletion rates and OPEC production policies. We believe demand is largely driven by global economic factors, such as population and income growth, governmental policies and vehicle stocks. The prices we use in our fair value estimates are consistent with those used in our planning and capital investment reviews. There has been significant volatility in crude oil and condensate, NGLs and natural gas and synthetic crude oil prices and estimates of such future prices are inherently imprecise. See Item 1A. Risk Factors for further discussion on commodity prices.
Estimated quantities of crude oil and condensate, NGLs and natural gas and synthetic crude oil.gas. Such quantities are based on a combination of proved reserves and risk-weighted probable reserves and resources such that the combined volumes represent the most likely expectation of recovery. See Item 1A. Risk Factors for further discussion on reserves.
Expected timing of production. Production forecasts are the outcome of engineerengineering studies which estimate reserves, as well as expected capital development programs. The actual timing of the production could be different than the projection. Cash flows realized later in the projection period are less valuable than those realized earlier due to the time value of money. The expected timing of production that we use in our fair value estimates is consistent with that used in our planning and capital investment reviews.
Discount rate commensurate with the risks involved. We apply a discount rate to our expected cash flows based on a variety of factors, including market and economic conditions, operational risk, regulatory risk and political risk. A higher discount rate decreases the net present value of cash flows.
Future capital requirements. Our estimates of future capital requirements are based upon a combination of authorized spending and internal forecasts.
We base our fair value estimates on projected financial information which we believe to be reasonably likely to occur. An estimate of the sensitivity to changes in assumptions in our undiscounted cash flow calculations is not practicable, given the numerous assumptions (e.g. reserves, pace and timing of development plans, commodity prices, capital expenditures, operating costs, drilling and development costs, inflation and discount rates) that can materially affect our estimates. Unfavorable adjustments to some of the above listed assumptions would likely be offset by favorable adjustments in other assumptions. For example, the impact of sustained reduced commodity prices on future undiscounted cash flows would likely be partially offset by lower costs.
Impairment Assessments of Goodwill
Goodwill must beis tested for impairment at least annually,on an annual basis, or between annual tests if an event occurswhen events or changes in circumstances change that would more likely than not reduceindicate the fair value of a reporting unit with goodwill may have been reduced below its carrying amount.value. Goodwill is tested for impairment at the reporting unit level. Our reporting units are the same as our reporting segments, of which only International E&P includes goodwill. We performed our annual impairment test in April 2016the second quarter of 2017 for the International E&P reporting unit and no impairment was required. Based on the results of these assessments, we fully impaired the goodwill associated with our North America E&P reporting unit. As of the date of our last goodwill impairment assessment, our International E&P reporting unit fair value exceeded its book value of $115 million by 26%over 40%.
We estimate the fair values of theour International E&P reporting unit using a combination of market and income approaches. Determining the fair value of a reporting unit requires judgment and the use of significant estimates and assumptions. The market approach referenced observable inputs specific to us and our industry.industry, such as the price of our common equity, our enterprise value, and valuation multiples of us and our peers from the investor analyst community. The income approach calculated the present value of expected futureutilizes discounted cash flows, which wereare based on forecasted assumptions. Key assumptions to the income approach are the same as those described above regarding our impairment assessment of long-lived assets.long lived assets and are consistent with those that management uses to make business decisions. We believe the estimates and assumptions used in our impairment assessments are reasonable and based on available market information, but variations in such assumptions could result in materially different calculations of fair value and determinations of whether or not an impairment is indicated. See Item 8. Financial Statements and Supplementary Data Note 1412 to the consolidated financial statements for additional discussion of goodwill.
Derivatives
We record all derivative instruments at fair value. Fair value measurements for all our derivative instruments are based on observable market-based inputs that are corroborated by market data and are discussed in Item 8. Financial Statements and Supplementary Data – Note 1513 to the consolidated financial statements. Additional information about derivatives and their valuation may be found in Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Income Taxes
We are subject to income taxes in numerous taxing jurisdictions worldwide. Estimates of income taxes to be recorded involve interpretation of complex tax laws and assessment of the effects of foreign taxes on our U.S. federal income taxes.
Uncertainty exists regarding tax positions taken in previously filed tax returns which remain subject to examination, along with positions expected to be taken in future returns. We provide for unrecognized tax benefits, based on the technical merits, when it is more likely than not that an uncertain tax position will not be sustained upon examination. Adjustments are made to the uncertain tax positions when facts and circumstances change, such as the closing of a tax audit; court proceedings; changes in applicable tax laws, including tax case rulings and legislative guidance; or expiration of the applicable statute of limitations.
On December 22, 2017, the United States enacted the Tax Cuts and Jobs Act ("Tax Reform Legislation"), which made significant changes to U.S. federal income tax law. We expect that certain aspects of the Tax Reform Legislation will positively impact our future after-tax earnings in the U.S., primarily due to the lower federal statutory tax rate. The Tax Reform Legislation is a comprehensive bill containing several other provisions, such as limitations on the deductibility of interest expense and certain executive compensation, that are not expected to have a material effect on our results. The ultimate impact of the Tax Reform Legislation may differ from our estimates due to changes in interpretations and assumptions made by us, as well as additional regulatory guidance that may be issued. Item 8. Financial Statements and Supplementary Data – Note 7 to the consolidated financial statements for further disclosure regarding Tax Reform Legislation.
We have recorded deferred tax assets and liabilities, measured at enacted tax rates, for temporary differences between book basis and tax basis, tax credit carryforwards and operating loss carryforwards. WeIn accordance with U.S. GAAP accounting standards, we routinely assess the realizability of our deferred tax assets and reduce such assets, to the expected realizable amount, by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. In assessing the need for additional or adjustments to existing valuation allowances, we consider the preponderance of evidence concerning the realization of the deferred tax asset. We must consider any prudent and feasible tax planning strategies that might minimize the amount of deferred tax liabilities recognized or the amount of any valuation allowance recognized against deferred tax assets, if we can implement the strategies and if we expect to implement them in the event the forecasted conditions actually occur. This assessment requires analysis of all available positive and negative evidence. Positive evidence includes reversals of temporary differences, forecasts of future taxable income, assessment of future business assumptions and applicable tax planning strategies.strategies that are prudent and feasible. Negative evidence includes losses in recent years as well as the forecasts of future income (loss) in the realizable period.
We expect to be in a cumulative loss position in early 2017, which constitutes significant objective negative evidence as to the future realizability of the value of our deferred tax assets. As a result, we are limited in our ability to consider forecasts for taxable income in future years in connection with In making our assessment ofregarding valuation allowances, we weight the realizability of our foreign tax credits and other federal deferred tax assets. Additionally, we considered the reversals of existing deferred tax assets and liabilities related to temporary differences between the book and tax basis of our assets and liabilities and concluded that it is more likely than not that a portion of our deferred tax assets would not be realized. Therefore, we increased our valuation allowanceevidence based on our federal deferred tax assets by $1,346 million in 2016. Our remaining U.S. operating loss carryforwards of $1.8 billion, which expire in 2035 and 2036, represent the federal deferred tax asset most at risk for an additional valuation allowance at December 31, 2016. See further detail in Item 8. Financial Statements and Supplementary Data - Note 9 to the consolidated financial statements.objectivity.
We base our future taxable income estimates on projected financial information which we believe to be reasonably likely to occur. Numerous judgments and assumptions are inherent in the estimation of future taxable income, including factors such as future operating conditions and the assessment of the effects of foreign taxes on our U.S. federal income taxes. Future operating conditions can be affected by numerous factors, including (i) future crude oil and condensate, NGLs and natural gas and synthetic crude oil prices, (ii) estimated quantities of crude oil and condensate, NGLs and natural gas, and synthetic crude oil, (iii) expected timing of production, and (iv) future capital requirements. These assumptions are described in further detail above regarding our impairment assessment of long-lived assets, see above for further detail describing these assumptions.assets. An estimate of the sensitivity to changes in assumptions resulting in future taxable income calculations is not practicable, given the numerous assumptions that can materially affect our estimates. Unfavorable adjustments to some of the above listed assumptions would likely be offset by favorable adjustments in other assumptions. For example, the impact of sustained reduced commodity prices on future taxable income would likely be partially offset by lower costs.capital expenditures.
Based on the assumptions and judgments described above, as of December 31, 2017, we reflect a valuation allowance in our Consolidated Balance Sheet of $926 million against our gross deferred tax assets of $2.0 billion in various jurisdictions in which we operate. Our gross deferred tax assets consist primarily of federal U.S. operating loss carryforwards of $898 million, which will expire in 2035, 2036 and 2037. Since December 31, 2016, we have maintained a full valuation allowance on our net federal deferred tax assets. If objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as forecasted projections of taxable income in future years, we would adjust the amount of the federal deferred tax assets considered realizable and reduce the provision for income taxes in the period of adjustment.
Pension and Other Postretirement Benefit Obligations
Accounting for pension and other postretirement benefit obligations involves numerous assumptions, the most significant of which relate to the following:
the discount rate for measuring the present value of future plan obligations;
the expected long-term return on plan assets;
the rate of future increases in compensation levels; and
health care cost projections.
We develop our demographics and utilize the work of third-party actuaries to assist in the measurement of these obligations. We have selected different discount rates for our U.S. pension plans and our other U.S. postretirement benefit plans due to the different projected benefit payment patterns. In determining the assumed discount rates, our methods include a

review of market yields on high-quality corporate debt and use of our third-party actuary's discount rate model. This model calculates an equivalent single discount rate for the projected benefit plan cash flows using a yield curve derived from bond yields. The yield curve represents a series of annualized individual spot discount rates from 0.5 to 99 years. The bonds used are rated AA or higher by a recognized rating agency, only non-callable bonds are included and outlier bonds (bonds that have a yield to maturity that significantly deviates from the average yield within each maturity grouping) are removed. Each issue is required to have at least $250 million par value outstanding. The constructed yield curve is based on those bonds representing the 50% highest yielding issuances within each defined maturity group.
Of the assumptions used to measure obligations and estimated annual net periodic benefit cost as of December 31, the discount rate has the most significant effect on the periodic benefit cost reported for the plans. The hypothetical impacts of a

0.25% change in the discount rates of 4.02%3.55% for our U.S. pension plans and 3.98%3.54% for our other U.S. postretirement benefit plans is summarized in the table below:
Impact of a 0.25% Increase in Discount Rate Impact of a 0.25% Decrease in Discount RateImpact of a 0.25% Increase in Discount Rate Impact of a 0.25% Decrease in Discount Rate
(In millions)Obligation Expense Obligation ExpenseObligation Expense Obligation Expense
U.S. pension plans$(5) $
 $6
 $
$(4) $
 $4
 $
Other U.S. postretirement benefit plans$(5) $
 $5
 $
$(5) $
 $5
 $
The asset rate of return assumption for the funded U.S. plan considers the plan's asset mix (currently targeted at approximately 55% equity and 45% other fixed income securities), past performance and other factors. Certain components of the asset mix are modeled with various assumptions regarding inflation, debt returns and stock yields. Decreasing the 6.75%6.50% asset rate of return assumption by 0.25% would not have a significant impact on our defined benefit pension expense.
Compensation change assumptions are based on historical experience, anticipated future management actions and demographics of the benefit plans. Health care cost trend assumptions are developed based on historical cost data, the near-term outlook and an assessment of likely long-term trends.
Item 8. Financial Statements and Supplementary Data – Note 2017 to the consolidated financial statements includes detailed information about the assumptions used to calculate the components of our annual defined benefit pension and other postretirement plan expense, as well as the obligations and accumulated other comprehensive income reported on the consolidated balance sheets.
Contingent Liabilities
We accrue contingent liabilities for environmental remediation, tax deficiencies related to operating taxes, as well as tax disputes and litigation claims when such contingencies are probable and estimable. Actual costs can differ from estimates for many reasons. For instance, settlement costs for claims and litigation can vary from estimates based on differing interpretations of laws, opinions on responsibility and assessments of the amount of damages. Similarly, liabilities for environmental remediation may vary from estimates because of changes in laws, regulations and their interpretation, additional information on the extent and nature of site contamination and improvements in technology. Our in-house legal counsel regularly assesses these contingent liabilities. In certain circumstances outside legal counsel is utilized.
We generally record losses related to these types of contingencies as other operating expense or general and administrative expense in the consolidated statements of income, except for tax contingencies unrelated to income taxes, which are recorded as taxes other than income. For additional information on contingent liabilities, see Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations – Management’s Discussion and Analysis of Environmental Matters, Litigation and Contingencies.
An estimate of the sensitivity to net income if other assumptions had been used in recording these liabilities is not practical because of the number of contingencies that must be assessed, the number of underlying assumptions and the wide range of reasonably possible outcomes, in terms of both the probability of loss and the estimates of such loss.
Accounting Standards Not Yet Adopted
See Item 8. Financial Statements and Supplementary Data – Note 2 to the consolidated financial statements.


Item 7A. Quantitative and Qualitative Disclosures About Market Risk
We are exposed to market risks related to the volatility of crude oil and condensate, NGLs, and natural gas and synthetic crude oil prices as the volatility of these prices continues to impact our industry. We expect commodity prices to remain volatile and unpredictable in the future. We are also exposed to market risks related to changes in interest rates and foreign currency exchange rates. We employ various strategies, including the use of financial derivative instruments, to manage the risks related to these fluctuations. We are at risk for changes in the fair value of all of our derivative instruments; however, such risk should be mitigated by price or rate changes related to the underlying commodity or financial transaction. While the use of derivative instruments could materially affect our results of operations in particular quarterly or annual periods, we believe that the use of these instruments will not have a material adverse effect on our financial position or liquidity.
See Item 8. Financial Statements and Supplementary Data – Notes 1513 and 1614 to the consolidated financial statements for more information about the fair value measurement of our derivatives, the amounts recorded in our consolidated balance sheets and statements of income and the related notional amounts.
Commodity Price Risk
Our strategy is to obtain competitive prices for our products and allow operating results to reflect market price movements dictated by supply and demand. However, management will periodically protect prices on forecasted sales to support cash flow and liquidity, as deemed appropriate. We may use a variety of commodity derivative instruments, including futures, forwards, swaps and combinations of options, as part of an overall program to manage commodity price risk in our business. Our consolidated results for 20162017 and 20152016 were impacted by crude oil and natural gas derivatives related to a portion of our forecasted North AmericaUnited States E&P sales. The table below provides a summary of open positions as of December 31, 20162017 and the weighted average price for those contracts:
Crude Oil (a)
20172018 2019
First Quarter Second Quarter Third Quarter Fourth QuarterFirst Quarter Second Quarter Third Quarter Fourth Quarter First Quarter Second Quarter
Three-Way Collars (b)(a)
     
Volume (Bbls/day)50,000 50,000 30,000 30,00085,000 85,000 85,000 85,000 10,000 10,000
Price per Bbl: 
Weighted average price per Bbl:   
Ceiling$58.42 $58.42 $59.60 $59.60$56.38 $56.38 $56.96 $56.96 $60.00 $60.00
Floor$50.30 $50.30 $54.00 $54.00$51.65 $51.65 $51.53 $51.53 $55.00 $55.00
Sold put$43.50 $43.50 $47.00 $47.00$45.00 $45.00 $44.65 $44.65 $47.00 $47.00
Sold Call Options (c)
 
Swaps   
Volume (Bbls/day)35,000 35,000 35,000 35,00020,000 20,000    
Price per Bbl$61.91 $61.91 $61.91 $61.91
Weighted average price per Bbl$55.12 $55.12 $— $— $— $—
Basis Swaps (b)
   
Volume (Bbls/day)5,000 5,000 10,000 10,000  
Weighted average price per Bbl$(0.60) $(0.60) $(0.67) $(0.67) $— $—
(a) 
Subsequent to December 31, 2016,Between January 1, 2018 and February 12, 2018, we entered into 10,000 Bbls/day of fixed-price swapsthree-way collars for July - December 2018 with a weightedan average price of $54.00 indexed to WTI for February - March of 2017.ceiling
price of $63.51, a floor price of $57.00, and a sold put price of $50.00 and 20,000 Bbls/day of three-way collars for January - June 2019 with an average ceiling price of $67.92, a floor price of $53.50, and a sold put price of $46.50.
(b) 
Subsequent to December 31, 2016, we entered into 20,000 Bbls/day of three-way collars for July - December of 2017 with a ceilingThe basis differential price of $61.52, a floor price of $56.00,is between WTI Midland and a sold put price of $49.00.WTI Cushing.
(c)
Call options settle monthly.


Natural Gas
201720182018
First QuarterSecond QuarterThird QuarterFourth Quarter First QuarterSecond QuarterThird QuarterFourth Quarter
Three-Way Collars (a)
 
Three-Way Collars 
Volume (MMBtu/day)60,00090,00020,000200,000160,000
Price per MMBtu 
Weighted average price per MMBtu 
Ceiling$3.46$3.54$3.61$3.56$3.79$3.61
Floor$2.84$3.01$3.04$3.00$3.08$3.00
Sold put$2.35$2.48$2.52$2.50$2.55$2.50
Swap 
Volume (MMBtu/day)20,000
Price per MMBtu2.93
(a)
Subsequent to December 31, 2016, we entered into three-way collars of 30,000 MMBtus/day for April - September of 2017 with a ceiling price of $3.70, a floor price of $3.35, and a sold put price of $2.75; 30,000 MMBtus/day for October - December of 2017 with a ceiling price of $4.00, a floor price of $3.45, and a sold put price of $2.85; and 70,000 MMBtus/day for January - December of 2018 with a ceiling price of $3.62, a floor price of $3.00, and a sold put price of $2.50.
The following table provides a sensitivity analysis of the projected incremental effect on income (loss) from operations of a hypothetical 10% change in NYMEX WTI and Henry Hub prices on our open commodity derivative instruments as of December 31, 2016:2017:
(In millions)Hypothetical Price Increase of 10%Hypothetical Price Decrease of 10%Hypothetical Price Increase of 10%Hypothetical Price Decrease of 10%
Crude oil derivatives(79)56
$(180)$149
Natural gas derivatives(11)13
(8)7
Total(90)69
$(188)$156
Interest Rate Risk
At December 31, 2016,2017, our portfolio of long-term debt was substantially comprised of fixed rate instruments. We currently manage our exposure to interest rate movements by utilizing interest rate swap agreements that effectively convert a portion of our fixed rate debt to floating interest rate debt. As of December 31, 2016, we had multiple interest rate swap agreements with a total notional of $900 million designated as fair value hedges. We additionally use forward starting interest rate swaps to manage our risk of interest rate changes during the period prior to anticipated borrowings. As of December 31, 2016, we had multiple forward starting interest rate swap agreements with a total notional of $750 million designated as cash flow hedges.
Our sensitivity to interest rate movements and corresponding changes in the fair value of our fixed rate debt portfolio affects our results of operations and cash flows only when we elect to repurchase or otherwise retire fixed-rate debt at prices different than carrying value. Sensitivity analysis of the incremental effect of a hypothetical 10% decreasechange in interest rates on our financial assets and liabilities as of December 31, 2016,2017, is provided in the following table.
  Incremental
  Change in
(In millions) Fair Value Fair ValueFair Value Hypothetical Price Increase of 10%Hypothetical Price Decrease of 10%
Financial assets (liabilities): (a)
       
Interest rate cash flow hedges64
(b) 
(16)
Interest rate fair value hedges$4
(b) 
$1
Long-term debt, including amounts due within one year$(7,449)
(b)(c) 
$(265)$(5,976)
(b)(c) 
$190
$(202)
(a) 
Fair values of cash and cash equivalents, receivables, accounts payable and accrued interest approximate carrying value and are relatively insensitive to changes in interest rates due to the short-term maturity of the instruments. Accordingly, these instruments are excluded from the table.
(b) 
Fair value was based on market prices where available, or current borrowing rates for financings with similar terms and maturities.
(c) 
Excludes capital leases.
Counterparty Risk
We are also exposed to financial risk in the event of nonperformance by counterparties. If commodity prices continue to remain low,fall below current levels, some of our counterparties may experience liquidity problems and may not be able to meet their financial obligations to us. We review the creditworthiness of counterparties and use master netting agreements when appropriate.

Item 8. Financial Statements and Supplementary Data
Index
 Page
  
  
  
  
 
  
  
  
  
  
  
  
  
  
  


Management’s Responsibilities for Financial Statements
To the Stockholders of Marathon Oil Corporation:
The accompanying consolidated financial statements of Marathon Oil Corporation and its consolidated subsidiaries ("Marathon Oil") are the responsibility of management and have been prepared in conformity with accounting principles generally accepted in the United States. They necessarily include some amounts that are based on best judgments and estimates. The financial information displayed in other sections of this Annual Report on Form 10-K is consistent with these consolidated financial statements.
Marathon Oil seeks to assure the objectivity and integrity of its financial records by careful selection of its managers, by organization arrangements that provide an appropriate division of responsibility and by communications programs aimed at assuring that its policies and methods are understood throughout the organization.
The Board of Directors pursues its oversight role in the area of financial reporting and internal control over financial reporting through its Audit and Finance Committee. This Committee, composed solely of independent directors, regularly meets (jointly and separately) with the independent registered public accounting firm, management and internal auditors to monitor the proper discharge by each of their responsibilities relative to internal accounting controls and the consolidated financial statements.
 
/s/ Lee M. Tillman  /s/ Patrick J. WagnerDane E. Whitehead   
President and Chief Executive Officer  InterimExecutive Vice President and Chief Financial Officer and Vice President-Corporate Development and Strategy   


Management’s Report on Internal Control over Financial Reporting
To the Stockholders of Marathon Oil Corporation:
Marathon Oil’s management is responsible for establishing and maintaining adequate internal control over financial reporting (as defined in Rules 13(a) – 15(f) under the Securities Exchange Act of 1934). Our internal control over financial reporting is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of the consolidated financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements and even when determined to be effective, can only provide reasonable assurance with respect to financial statement preparation and presentation. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions or that the degree of compliance with the policies or procedures may deteriorate.
An evaluation of the design and effectiveness of our internal control over financial reporting, based on the 2013 framework in Internal Control – Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission, was conducted under the supervision and with the participation of management, including our Chief Executive Officer and Chief Financial Officer. Based on the results of this evaluation, Marathon Oil’s management concluded that its internal control over financial reporting was effective as of December 31, 2016.2017.
The effectiveness of Marathon Oil’s internal control over financial reporting as of December 31, 20162017 has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their report which is included herein.
/s/ Lee M. Tillman  /s/ Patrick J. WagnerDane E. Whitehead  
President and Chief Executive Officer  InterimExecutive Vice President and Chief Financial Officer and Vice President-Corporate Development and Strategy  

Report of Independent Registered Public Accounting Firm


To the Board of Directors and Stockholders of Marathon Oil Corporation:
Opinions on the Financial Statements and Internal Control over Financial Reporting
We have audited the accompanying consolidated balance sheets of Marathon Oil Corporation and its subsidiaries as of December 31, 2017 and 2016, and the related consolidated statements of income, comprehensive income, cash flows and stockholders’ equity for each of the three years in the period ended December 31, 2017, including the related notes (collectively referred to as the “consolidated financial statements”). We also have audited the Company's internal control over financial reporting as of December 31, 2017, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).
In our opinion, the consolidated financial statements listed in the accompanying indexreferred to above present fairly, in all material respects, the financial position of Marathon Oil Corporation and its subsidiaries (the “Company”) atthe Company as of December 31, 20162017 and 2015,2016, and the results of their operations and their cash flows for each of the three years in the period ended December 31, 2016,2017 in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2016,2017, based on criteria established in Internal Control - Integrated Framework - 2013(2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). COSO.
Basis for Opinions
The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control over Financial Reporting. Our responsibility is to express opinions on thesethe Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our integrated audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States).PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.
Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence supportingregarding the amounts and disclosures in the consolidated financial statements, assessingstatements. Our audits also included evaluating the accounting principles used and significant estimates made by management, andas well as evaluating the overall presentation of the consolidated financial statement presentation.statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

Definition and Limitations of Internal Control over Financial Reporting
A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.
Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.


/s/ PricewaterhouseCoopers LLP
Houston, Texas
February 24, 201722, 2018

We have served as the Company’s auditor since 1982.


MARATHON OIL CORPORATION
Consolidated Statements of Income
Year Ended December 31,Year Ended December 31,
(In millions, except per share data)2016 2015 20142017 2016 2015
Revenues and other income:          
Sales and other operating revenues, including related party$3,753
 $4,951
 $8,736
$4,211
 $2,930
 $4,136
Marketing revenues278
 571
 2,110
162
 240
 499
Income from equity method investments175
 145
 424
256
 175
 145
Net gain (loss) on disposal of assets389
 120
 (90)58
 389
 120
Other income55
 74
 78
78
 53
 53
Total revenues and other income4,650
 5,861
 11,258
4,765
 3,787
 4,953
Costs and expenses:          
Production1,313
 1,694
 2,246
706
 712
 979
Marketing, including purchases from related parties282
 569
 2,105
168
 245
 500
Other operating511
 438
 462
431
 484
 410
Exploration330
 1,318
 793
409
 323
 971
Depreciation, depletion and amortization2,395
 2,957
 2,861
2,372
 2,156
 2,721
Impairments67
 752
 132
229
 67
 721
Taxes other than income168
 234
 406
183
 151
 216
General and administrative484
 590
 654
400
 481
 588
Total costs and expenses5,550
 8,552
 9,659
4,898
 4,619
 7,106
Income (loss) from operations(900) (2,691) 1,599
(133) (832) (2,153)
Net interest and other(335) (267) (238)(270) (332) (286)
Loss on early extinguishment of debt(51) 
 
Income (loss) from continuing operations before income taxes(1,235) (2,958) 1,361
(454) (1,164) (2,439)
Provision (benefit) for income taxes905
 (754) 392
376
 923
 (738)
Income (loss) from continuing operations(2,140) (2,204) 969
(830) (2,087) (1,701)
Discontinued operations
 
 2,077
Income (loss) from discontinued operations(4,893) (53) (503)
Net income (loss)$(2,140) $(2,204) $3,046
$(5,723) $(2,140) $(2,204)
Per Share Data          
Basic:          
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
$(0.97) $(2.55) $(2.51)
Discontinued operations$
 $
 $3.06
Income (loss) from discontinued operations$(5.76) $(0.06) $(0.75)
Net income (loss)$(2.61) $(3.26) $4.48
$(6.73) $(2.61) $(3.26)
Diluted:          
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
$(0.97) $(2.55) $(2.51)
Discontinued operations$
 $
 $3.04
Income (loss) from discontinued operations$(5.76) $(0.06) $(0.75)
Net income (loss)$(2.61) $(3.26) $4.46
$(6.73) $(2.61) $(3.26)
Dividends$0.20
 $0.68
 $0.80
$0.20
 $0.20
 $0.68
Weighted average shares:          
Basic819
 677
 680
850
 819
 677
Diluted819
 677
 683
850
 819
 677
The accompanying notes are an integral part of these consolidated financial statements.

MARATHON OIL CORPORATION
Consolidated Statements of Comprehensive Income
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Net income (loss)$(2,140) $(2,204) $3,046
$(5,723) $(2,140) $(2,204)
Other comprehensive income (loss)          
Postretirement and postemployment plans          
Change in actuarial loss and other16
 228
 (52)21
 16
 228
Income tax benefit (provision)(4) (86) 25
Income tax provision (benefit)7
 (4) (86)
Postretirement and postemployment plans, net of tax12
 142
 (27)28
 12
 142
Derivative hedges          
Net unrecognized gain61
 
 1
Income tax provision(22) 
 
Net unrecognized gain (loss)(13) 61
 
Reclassification of gains on terminated derivative hedges(47) 
 
Income tax provision (benefit)21
 (22) 
Derivative hedges, net of tax39
 
 1
(39) 39
 
Foreign currency hedges     
Net recognized loss reclassified to discontinued operations34
 
 
Income tax provision (benefit)(4) 
 
Foreign currency hedges, net of tax30
 
 
Other, net of tax1
 
 (1)2
 1
 
Other comprehensive income (loss)52
 142
 (27)21
 52
 142
Comprehensive income (loss)$(2,088) $(2,062) $3,019
$(5,702) $(2,088) $(2,062)
The accompanying notes are an integral part of these consolidated financial statements.


MARATHON OIL CORPORATION
Consolidated Balance Sheets
December 31,December 31,
(In millions, except par values and share amounts)2016 20152017 2016
Assets      
Current assets:      
Cash and cash equivalents$2,490
 $1,221
$563
 $2,488
Receivables, less reserve of $6 and $4877
 912
Receivables, less reserve of $12 and $61,082
 748
Notes receivable748
 
Inventories227
 313
126
 136
Other current assets71
 144
36
 66
Current assets held for sale11
 227
Total current assets3,665
 2,590
2,566
 3,665
Equity method investments931
 1,003
847
 931
Property, plant and equipment, less accumulated depreciation, 
  
 
  
depletion and amortization of $22,214 and $23,26025,718
 27,061
depletion and amortization of $21,564 and $20,25517,665
 16,727
Goodwill115
 115
115
 115
Other noncurrent assets665
 1,542
764
 558
Noncurrent assets held for sale55
 9,098
Total assets$31,094
 $32,311
$22,012
 $31,094
Liabilities      
Current liabilities:      
Accounts payable1,078
 1,313
$1,395
 $967
Payroll and benefits payable129
 133
108
 129
Accrued taxes94
 132
177
 94
Other current liabilities253
 150
288
 243
Long-term debt due within one year686
 1

 686
Current liabilities held for sale
 121
Total current liabilities2,240
 1,729
1,968
 2,240
Long-term debt6,589
 7,276
5,494
 6,581
Deferred tax liabilities2,438
 2,441
833
 769
Defined benefit postretirement plan obligations345
 403
362
 345
Asset retirement obligations1,697
 1,601
1,428
 1,602
Deferred credits and other liabilities244
 308
217
 225
Noncurrent liabilities held for sale2
 1,791
Total liabilities13,553
 13,758
10,304
 13,553
Commitments and contingencies
 


 

Stockholders’ Equity      
Preferred stock - no shares issued or outstanding (no par value,      
26 million shares authorized)
 

 
Common stock:      
Issued – 937 million and 770 million shares, respectively (par value $1 per share, 1.1 billion shares authorized)937
 770
Securities exchangeable into common stock – no shares issued 
  
or outstanding (no par value, 29 million shares authorized)
 
Held in treasury, at cost – 90 million and 93 million shares(3,431) (3,554)
Issued – 937 million and 937 million shares, respectively (par value $1 per share, 1.1 billion shares authorized)937
 937
Held in treasury, at cost – 87 million and 90 million shares(3,325) (3,431)
Additional paid-in capital7,446
 6,498
7,379
 7,446
Retained earnings12,672
 14,974
6,779
 12,672
Accumulated other comprehensive loss(83) (135)(62) (83)
Total stockholders' equity17,541
 18,553
11,708
 17,541
Total liabilities and stockholders' equity$31,094
 $32,311
$22,012
 $31,094
The accompanying notes are an integral part of these consolidated financial statements.

MARATHON OIL CORPORATION
Consolidated Statements of Cash Flows
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Increase (decrease) in cash and cash equivalents          
Operating activities: 
     
    
Net income (loss)$(2,140) $(2,204) $3,046
$(5,723) $(2,140) $(2,204)
Adjustments to reconcile net income (loss) to net cash provided by operating activities: 
     
    
Discontinued operations
 
 (2,077)4,893
 53
 503
Depreciation, depletion and amortization2,395
 2,957
 2,861
2,372
 2,156
 2,721
Impairments67
 752
 132
229
 67
 721
Exploratory dry well costs and unproved property impairments227
 1,214
 623
323
 220
 867
Net (gain) loss on disposal of assets(389) (120) 90
(58) (389) (120)
Deferred income taxes811
 (806) 88
(61) 828
 (804)
Net (gain) loss on derivative instruments63
 (126) (4)(11) 63
 (126)
Net cash received (paid) in settlement of derivative instruments61
 55
 (5)98
 61
 55
Pension and other postretirement benefits, net(3) 1
 (34)
Stock based compensation48
 44
 52
50
 48
 45
Equity method investments, net17
 33
 27
20
 17
 33
Changes in:          
Current receivables50
 817
 119
(334) 67
 790
Inventories75
 36
 (11)10
 64
 25
Current accounts payable and accrued liabilities(133) (965) (33)297
 (137) (906)
All other operating, net(76) (123) (138)(117) (77) (63)
Net cash provided by continuing operations1,073
 1,565
 4,736
Net cash provided by discontinued operations
 
 751
Net cash provided by operating activities1,073
 1,565
 5,487
Net cash provided by operating activities from continuing operations1,988
 901
 1,537
Investing activities:          
Additions to property, plant and equipment(1,245) (3,476) (5,160)(1,974) (1,204) (3,485)
Acquisitions, net of cash acquired(902) 
 (21)(1,891) (902) 
Disposal of assets1,219
 225
 3,760
Disposal of assets, net of cash transferred to the buyer1,787
 1,219
 225
Equity method investments - return of capital55
 77
 61
64
 55
 77
Investing activities of discontinued operations
 
 (376)
Purchases of short term investments
 (925) 

 
 (925)
Maturities of short term investments
 925
 

 
 925
All other investing, net(1) (28) (10)(30) (1) 24
Net cash used in investing activities(874) (3,202) (1,746)
Net cash used in investing activities from continuing operations(2,044) (833) (3,159)
Financing activities:          
Borrowings
 1,996
 
988
 
 1,996
Debt repayments(1) (1,069) (68)(2,764) (1) (1,069)
Debt extinguishment costs(46) 
 
Common stock issuance
 1,236
 
Purchases of common stock
 
 (1,000)(11) (6) (11)
Issuance of common stock1,236
 
 
Dividends paid(162) (460) (543)(170) (162) (460)
All other financing, net1
 (5) 18

 1
 (5)
Net cash provided by (used in) financing activities1,074
 462
 (1,593)(2,003) 1,068
 451
Effect of exchange rate changes on cash:     
Continuing operations(4) (2) (2)
Discontinued operations
 
 (12)
Cash Flow from Discontinued Operations:     
Operating activities141
 177
 39
Investing activities(13) (41) (43)
Changes in cash included in current assets held for sale2
 100
 90
Net increase in cash and cash equivalents of discontinued operations130
 236
 86
Effect of exchange rate changes on cash and cash equivalents:4
 (3) (3)
Net increase (decrease) in cash and cash equivalents1,269
 (1,177) 2,134
(1,925) 1,369
 (1,088)
Cash and cash equivalents at beginning of period1,221
 2,398
 264
2,488
 1,119
 2,207
Cash and cash equivalents at end of period$2,490
 $1,221
 $2,398
$563
 $2,488
 $1,119
The accompanying notes are an integral part of these consolidated financial statements.

MARATHON OIL CORPORATION
Consolidated Statements of Stockholders’ Equity
Total Equity of Marathon Oil Stockholders  Total Equity of Marathon Oil Stockholders  
(In millions)
Preferred
Stock
 
Common
Stock
 
Securities
Exchangeable
into Common
Stock
 
Treasury
Stock
 
Additional
Paid-in
Capital
 
Retained
Earnings
 
Accumulated
Other
Comprehensive
Loss
 
Total
Equity
Preferred
Stock
 
Common
Stock
 
Treasury
Stock
 
Additional
Paid-in
Capital
 
Retained
Earnings
 
Accumulated
Other
Comprehensive
Loss
 
Total
Equity
December 31, 2013 Balance$
 $770
 $
 $(2,903) $6,592
 $15,135
 $(250) $19,344
Shares issued - stock-based               
compensation
 
 
 276
 (57) 
 
 219
Shares repurchased
 
 
 (1,015) 
 
 
 (1,015)
Stock-based compensation
 
 
 
 (4) 
 
 (4)
Net income
 
 
 
 
 3,046
 
 3,046
Other comprehensive loss
 
 
 
 
 
 (27) (27)
Dividends paid
 
 
 
 
 (543) 
 (543)
December 31, 2014 Balance$
 $770
 $
 $(3,642) $6,531
 $17,638
 $(277) $21,020
$
 $770
 $(3,642) $6,531
 $17,638
 $(277) $21,020
Shares issued - stock-based                            
compensation
 
 
 96
 (32) 
 
 64

 
 96
 (32) 
 
 64
Shares repurchased
 
 
 (8) 
 
 
 (8)
 
 (8) 
 
 
 (8)
Stock-based compensation
 
 
 
 (1) 
 
 (1)
 
 
 (1) 
 
 (1)
Net income
 
 
 
 
 (2,204) 
 (2,204)
Other comprehensive income
 
 
 
 
 
 142
 142
Net loss
 
 
 
 (2,204) 
 (2,204)
Other comprehensive loss
 
 
 
 
 142
 142
Dividends paid
 
 
 
 
 (460) 
 (460)
 
 
 
 (460) 
 (460)
December 31, 2015 Balance$
 $770
 $
 $(3,554) $6,498
 $14,974
 $(135) $18,553
$
 $770
 $(3,554) $6,498
 $14,974
 $(135) $18,553
Shares issued - stock-based                            
compensation
 
 
 128
 (86) 
 
 42

 
 128
 (86) 
 
 42
Shares repurchased
 
 
 (5) 
 
 
 (5)
 
 (5) 
 
 
 (5)
Stock-based compensation
 
 
 
 (35) 
 
 (35)
 
 
 (35) 
 
 (35)
Net loss
 
 
 
 
 (2,140) 
 (2,140)
 
 
 
 (2,140) 
 (2,140)
Other comprehensive income
 
 
 
 
 
 52
 52

 
 
 
 
 52
 52
Dividends paid
 
 
 
 
 (162) 
 (162)
 
 
 
 (162) 
 (162)
Common stock issuance
 167
 
 
 1,069
 
 
 1,236

 167
 
 1,069
 
 
 1,236
December 31, 2016 Balance$
 $937
 $
 $(3,431) $7,446
 $12,672
 $(83) $17,541
$
 $937
 $(3,431) $7,446
 $12,672
 $(83) $17,541
               
(Shares in millions)
Preferred
Stock
 
Common
Stock
 
Securities
Exchangeable
into Common
Stock
 
Treasury
Stock
        
December 31, 2013 Balance
 770
 
 73
        
Shares issued - stock-based                            
compensation
 
 
 (7)        
 
 117
 (50) 
 
 67
Shares repurchased
 
 
 29
        
 
 (11) 
 
 
 (11)
Stock-based compensation
 
 
 (17) 
 
 (17)
Net loss
 
 
 
 (5,723) 
 (5,723)
Other comprehensive income
 
 
 
 
 21
 21
Dividends paid
 
 
 
 (170) 
 (170)
Common stock issuance
 
 
 
 
 
 
December 31, 2017 Balance$
 $937
 $(3,325) $7,379
 $6,779
 $(62) $11,708
             
(Shares in millions)
Preferred
Stock
 
Common
Stock
 
Treasury
Stock
        
December 31, 2014 Balance
 770
 
 95
        
 770
 95
        
Shares issued - stock-based                            
compensation
 
 
 (2)        
 
 (2)        
Shares repurchased
 
 
 
        
 
 
        
December 31, 2015 Balance
 770
 
 93
        
 770
 93
        
Shares issued - stock-based                            
compensation
 
 
 (3)        
 
 (3)        
Shares repurchased
 
 
 
        
 
 
        
Common stock issuance
 167
 
 
        
 167
 
        
December 31, 2016 Balance
 937
 
 90
 
      
 937
 90
        
Shares issued - stock-based             
compensation
 
 (3)        
Shares repurchased
 
 
        
Common stock issuance
 
 
        
December 31, 2017 Balance
 937
 87
 
      
The accompanying notes are an integral part of these consolidated financial statements.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements



1. Summary of Principal Accounting Policies
We are a global energy company engaged in exploration, production and marketing of crude oil and condensate, NGLs and natural gas; as well as production and marketing of products manufactured from natural gas, such as LNG and methanol, in E.G.; and oil sands mining, bitumen transportation and upgrading, and marketing of synthetic crude oil and vacuum gas oil in Canada.
Basis of presentation and principles applied in consolidation – These consolidated financial statements include the accounts of our majority-owned, controlled subsidiaries. Investments in unincorporated joint ventures and undivided interests in certain operating assets are consolidated on a pro rata basis.
Equity method investments – Investments in entities over which we have significant influence, but not control, are accounted for using the equity method of accounting. This includes entities in which we hold majority ownership but the minority stockholders have substantive participating rights in the investee. Income from equity method investments represents our proportionate share of net income generated by the equity method investees and is reflected in revenue and other income in our consolidated statements of income. Equity method investments are included as noncurrent assets on the consolidated balance sheet.
Equity method investments are assessed for impairment whenever changes in the facts and circumstances indicate a loss in value has occurred, if themay have occurred. When a loss is deemed to be other than temporary. When the losshave occurred and is deemed to be other than temporary, the carrying value of the equity method investment is written down to fair value, and the amount of the write-down is included in income. Differences in the basis of the investments and the separate net asset value of the investees, if any, are amortized into income over the remaining useful lives of the underlying assets, except for the excess related to goodwill.
Reclassifications – We have reclassified certain prior year amounts between operating cash flow categories to present it on a basis comparable with the current year's presentation with no impact on net cash provided by operating activities.
Discontinued operationsAs a result of the sale of our Canadian business in 2017, we reflected this business as discontinued operations in all periods presented. Disclosures in this report related to results of operations and cash flows are presented on the basis of continuing operations unless otherwise stated. Assets and liabilities are presented as held for sale in the historical periods in the consolidated balance sheets. See Note 5 for discussion of the divestiture in further detail.
As a result ofdiscussed above we closed on the sale of our Angola assetsCanadian business, which includes our Oil Sands Mining segment and exploration stage in-situ leases in the second quarter 2017. The characteristics and composition of our Norway business in 2014 (seeNorth America E&P reporting segment remained unchanged and there was no effect on previously reported segment information. As all our remaining properties within the segment are located within the United States, we concluded that our North America E&P segment would be renamed United States E&P segment, effective June 30, 2017. During the year, no changes occurred to our International E&P segment. See Note 6), these businesses are reflected as discontinued operations.6 for further information on our reportable segments.
Use of estimates – The preparation of financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities as of the date of the consolidated financial statements and the reported amounts of revenues and expenses during the respective reporting periods.
Estimated quantities of crude oil and condensate, NGLs and natural gas reserves is a significant estimate that requires judgment. All of the reserve data included in this Form 10-K are estimates. Reservoir engineering is a subjective process of estimating underground accumulations of crude oil and condensate, NGLs and natural gas. There are numerous uncertainties inherent in estimating quantities of proved crude oil and condensate, NGLs and natural gas reserves. The accuracy of any reserves estimate is a function of the quality of available data and of engineering and geological interpretation and judgment. As a result, reserve estimates may be different from the quantities of crude oil and condensate, NGLs and natural gas that are ultimately recovered. See Supplementary Data - Supplementary Information on Oil and gas Producing Activities for further detail.
Other items subject to estimates and assumptions include the carrying amounts of property, plant and equipment, asset retirement obligations, goodwill, valuation of derivative instruments and valuation allowances for deferred income tax assets, among others. Although we believe these estimates are reasonable, actual results could differ from these estimates.
Foreign currency transactions – The U.S. dollar is the functional currency of our foreign operating subsidiaries. Foreign currency transaction gains and losses are included in net income.
Revenue recognition – Revenues are recognized when products are shipped or services are provided to customers, title is transferred, the sales price is fixed or determinable and collectability is reasonably assured. We follow the sales method of
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


accounting for crude oil and natural gas production imbalances and would recognize a liability if our existing proved reserves were not adequate to cover an imbalance.imbalance. Imbalances have not been significant in the periods presented.
In the lower 48 states of the U.S., production volumes of crude oil and condensate, NGLs and natural gas are generally sold immediately and transported to market. In international locations, liquid hydrocarbon production volumes may be stored as inventory and sold at a later time. In Canada, mined bitumen is first processed through an upgrader and then sold as synthetic crude oil.
Cash and cash equivalents – Cash and cash equivalents include cash on hand and on deposit and investments in highly liquid debt instruments with original maturities of three months or less.
Short-term Investments - Our short-term investments are comprised of bank time deposits with original maturities of greater than three months but less than twelve months. They are classified as held-to-maturity investments, which are recorded at amortized cost.
Accounts receivable – The majority of our receivables are from joint interest owners in properties we operate or from purchasers of commodities, both of which are recorded at invoiced amounts and do not bear interest. We often have the ability to withhold future revenue disbursements to recover any non-payment of joint interest billings. We conduct credit reviews of commodity purchasers prior to making commodity sales to new customers or increasing credit for existing customers. Based on these reviews, we may require a standby letter of credit or a financial guarantee. Uncollectible accountsWe routinely assess the collectability of receivable are
MARATHON OIL CORPORATION
Notesbalances to Consolidated Financial Statements


reserved against the allowance for uncollectible accounts when it is determined the receivable will not be collected anddetermine if the amount of anythe reserve may be reasonably estimated.in allowance for doubtful accounts is sufficient.
Notes receivable - We hold two notes receivable from the sale of our Canadian business, which closed in the second quarter of 2017. Both notes receivable were initially recorded at fair value and are reported at amortized cost. The notes receivable are evaluated for collectability on an individual basis each reporting period, based on the financial condition of the debtor. No allowances for credit losses were established for the notes receivable as of December 31, 2017. See Note 5 for additional discussion.
Inventories – Crude oil and natural gas and bitumen are recorded at weighted average cost and carried at the lower of cost or marketnet realizable value. Supplies and other items consist principally of tubular goods and equipment which are valued at weighted average cost and reviewed periodically for obsolescence or impairment when market conditions indicate.indicate.
We may enter into a contract to sell a particular quantity and quality of crude oil at a specified location and datedate to a particular counterparty, and simultaneously agree to buy a particular quantity and quality of the same commodity at a specified location on the same or another specified date from the same counterparty. We account for such matching buy/sell arrangements as exchanges of inventory.
Derivative instruments – We may use derivatives to manage a portion of our exposure to commodity price risk, interest ratecommodity locational risk, foreign currency risk and foreign currency exchangeinterest rate risk. All derivative instruments are recorded at fair value. Commodity derivatives and interest rate swaps are reflected on our consolidated balance sheet on a net basis by counterparty, as they are governed by master netting agreements. Cash flows related to derivatives used to manage commodity price risk, foreign currency risk and interest rate risk are classified in operating activities. Our derivative instruments contain no significant contingent credit features.
Fair value hedges – We may use interest rate swaps to manage our exposure to interest rate risk associated with fixed interest rate debt in our portfolio and foreign currency forwards to manage our exposure to changes in the value of foreign currency denominated liabilities.portfolio. Changes in the fair values of both the hedged item and the related derivative are recognized immediately in net income with an offsetting effect included in the basis of the hedged item. The net effect is to report in net income the extent to which the hedge is not effective in achieving offsetting changes in fair value.
Cash flow hedges – We may use interest rate derivative instruments to manage the risk of interest rate changes during the period prior to anticipated borrowings and designate them as cash flow hedges. Derivative instruments designated as cash flow hedges are linked to specific assets and liabilities or to specific firm commitments or forecasted transactions. The effective portion of changes in the fair value of a qualifying cash flow hedge are recorded in other comprehensive income until the hedged item is reclassified to net income when the underlying forecasted transaction is recognized in net income. Ineffective portions of a cash flow hedge’s change in fair value are recognized currently within net interest and other on the consolidated statements of income. However, if it is determined that the likelihood of the original forecasted transaction occurring is no longer probable, the entire accumulated gain or loss recognized in other comprehensive income is immediately reclassified into net income.
Derivatives not designated as hedges – Derivatives that are not designated as hedges may include commodity derivatives used primarily to manage price riskand locational risks on the forecasted sale of crude oil and natural gas and synthetic crude oil that we produce. Changes in the fair value of derivatives not designated as hedges are recognized immediately in net income.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Concentrations of credit risk – All of our financial instruments, including derivatives, involve elements of credit and market risk. The most significant portion of our credit risk relates to nonperformance by counterparties. The counterparties to our financial instruments consist primarily of major financial institutions and companies within the energy industry. To manage counterparty risk associated with financial instruments, we select and monitor counterparties based on our assessment of their financial strength and on credit ratings, if available. Additionally, we limit the level of exposure with any single counterparty.
Fair value transfer – We recognize transfers between levels of the fair value hierarchy as of the end of the reporting period. If significant transfers occur, they would be disclosed in Note 1514 to the consolidated financial statements.
Property, plant and equipment – We use the successful efforts method of accounting for oil and gas producing activities, which include bitumen mining and upgrading.activities.
Property acquisition costs – Costs to acquire mineral interests in oil and natural gas properties, or in oil sands mines, to drill and equip exploratory wells in progress and those that find proved reserves, and to drill and equip development wells and to construct or expand oil sands mines and upgrading facilities are capitalized. Costs to drill exploratory wells that do not find proved reserves, geological and geophysical costs and costs of carrying and retaining unproved properties are expensed. Costs incurred for exploratory wells that find reserves but cannot yet be classified as proved are capitalized if (1) the well has found a sufficient quantity of reserves to justify its completion as a producing well and (2) we are making sufficient progress assessing the reserves and the economic and operating viability of the project. The status of suspended exploratory well costs is monitored continuously and reviewed at least quarterly.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Depreciation, depletion and amortization – Capitalized costs to acquire oil and natural gas properties which include bitumen mining and upgrading facilities, are depreciated and depleted on a units-of-production basis based on estimated proved reserves. Capitalized costs of exploratory wells and development costs are depreciated and depleted on a units-of-production basis based on estimated proved developed reserves. Support equipment and other property, plant and equipment related to oil and gas producing activities, as well as property, plant and equipment unrelated to oil and gas producing activities, are recorded at cost and depreciateddepreciated on a straight-line basis over the estimated useful lives of the assets as summarized below.
Type of Asset Range of Useful Lives
Office furniture, equipment and computer hardware 34 to 15 years
Pipelines 10 to 40 years
Plants, facilities mine equipment and infrastructure 3 to 40 years

ImpairmentsWe evaluateevaluate our oil and gas producing properties, including capitalized costs of exploratory wells and development costs, and our bitumen mining and upgrading facilities, for impairment of value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If the sum of the expected undiscounted future cash flows from the use of the asset and its eventual disposition is less than the carrying amount of the asset, an impairment loss is recognized based on the fair value of the asset. Oil and gas producing properties are reviewed for impairment on a field-by-field basis or, in certain instances, by logical grouping of assets if there is significant shared infrastructure or contractual terms that cause economic interdependency amongst separate, discrete fields. Oil and gas producing properties deemed to be impaired are written down to their fair value, as determined by discounted future net cash flows or, if available, comparable market value. We evaluate our unproved property investment and record impairment based on time or geologic factors. Information such as drilling results, reservoir performance, seismic interpretation or future plans to develop acreage is also considered. When unproved property investments are deemed to be impaired, this amount is reported in exploration expenses in our consolidated statements of income.
Dispositions – When property, plant and equipment depreciated on an individual basis is sold or otherwise disposed of, any gains or losses are reflected in net gain (loss) on disposal of assets in our consolidated statements of income. Gains on the disposal of property, plant and equipment are recognized when earned, which is generally at the time of closing. If a loss on disposal is expected, such losses are recognized either when the assets are classified as held for sale, or are measured using a probability weighted income approach based on both the anticipated sales price and a held-for-use model depending on timing of the sale. Proceeds from the disposal of property, plant and equipment depreciated on a group basis are credited to accumulated depreciation, depletion and amortization with no immediate effect on net income until net book value is reduced to zero.
Goodwill – Goodwill represents the excess of the purchase price over the estimated fair value of the net assets acquired in the acquisition of a business. Such goodwill is not amortized, but rather is tested for impairment annually and when events or changes in circumstances indicate that the fair value of a reporting unit with goodwill has been reduced below carrying value. The impairment test requires allocating goodwill and other assets and liabilities to a reporting unit. The fair value of a reporting unit is determined and compared to the book value of the reporting unit. If the fair value of the reporting unit is less than the book value, including goodwill, then the recorded goodwill is impaired to its implied fair value with a charge to impairments.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Major maintenance activities – Costs for planned major maintenance are expensed in the period incurred and can include the costs of contractor repair services, materials and supplies, equipment rentals and our labor costs.
Environmental costs – We provide for remediation costs and penalties when the responsibility to remediate is probable and the amount of associated costs can be reasonably estimated. The timing of remediation accruals coincides with completion of a feasibility study or the commitment to a formal plan of action. Remediation liabilities are accrued based on estimates of known environmental exposure and are discounted when the estimated amounts are reasonably fixed or reliably determinable. Environmental expenditures are capitalized only if the costs mitigate or prevent future contamination or if the costs improve the environmental safety or efficiency of the existing assets.
Asset retirement obligations – The fair value of asset retirement obligations is recognized in the period in which the obligations are incurred if a reasonable estimate of fair value can be made. Our asset retirement obligations primarily relate to the abandonment of oil and gas producing facilities, which include our bitumen mining facilities. Asset retirement obligations for such facilities include costs to dismantle and relocate or dispose of production platforms, mine assets, gathering systems, wells and related structures and restoration costs of land and seabed, including those leased. Estimates of these costs are developed for each property based on the type of production structure,facilities and equipment, depth of water, reservoir characteristics, depth of the reservoir, market demand for equipment, currently available procedures and consultations with construction and engineering professionals.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


professionals. Asset retirement obligations have not been recognized for certain of our international oil and gas producing facilities as we currently do not have a legal obligation associated with the retirement of those facilities. Asset retirement obligations have not been recognized for the removal of materials and equipment from or the closure of certain bitumen upgrading assets because the fair value cannot be reasonably estimated since the settlement dates of the obligations are indeterminate.
Inflation rates and credit-adjusted-risk-free interest rates are used to estimate the fair value of asset retirement obligations. Depreciation of capitalized asset retirement costs and accretion of asset retirement obligations are recorded over time. Depreciation is generally determined on a units-of-production basis based on estimated proved developed reserves for oil and gas production facilities, which include our bitumen mining facilities, while accretion escalatesof the liability occurs over the useful lives of the assets.
Deferred income taxes – Deferred tax assets and liabilities, measured at enacted tax rates, are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of assets and liabilities and their tax bases as reported in our filings with the respective taxing authorities. We routinely assess the realizability of our deferred tax assets based on several interrelated factors and reduce such assets by a valuation allowance if it is more likely than not that some portion or all of the deferred tax assets will not be realized. These factors include whether we are in a cumulative loss position in recent years, our reversal of temporary differences, and our expectation to generate sufficient future taxable income. We use the liability method in determining our provision and liabilities for our income taxes, under which current and deferred tax liabilities and assets are recorded in accordance with enacted tax laws and rates.
Stock-based compensation arrangements – The fair value of stock options is estimated on the date of grant using the Black-Scholes option pricing model. The model employs various assumptions, based on management’s best estimates at the time of grant, which impact the calculation of fair value and ultimately, the amount of expense that is recognized over the life of the stock option award. Of the required assumptions, the expected volatility of our stock price and the stock price in relation to the strike price have the most significant impact on the fair value calculation. We have utilized historical data and analyzed current information which reasonably support these assumptions.
The fair value of our restricted stock awards and common stock units is determined based on the market value of our common stock on the date of grant. Unearned stock-based compensation is charged to stockholders’ equity when restricted stock awards are granted.
The fair value of our stock-based performance units is estimated using the Monte Carlo simulation method. Since these awards are settled in cash at the end of a defined performance period, they are classified as a liability and are re-measured quarterly until settlement.
Our stock-based compensation expense is recognized based on management’s best estimate of the awards that are expected to vest, using the straight-line attribution method for all service-based awards with a graded vesting feature. If actual forfeiture results are different than expected, adjustments to recognized compensation expense may be required in future periods.
During the first quarter of 2017, we adopted the accounting standards update issued by the FASB in March 2016 pertaining to share-based payment transactions. As a result of this adoption, all cash payments for withheld shares made to taxing authorities on the employees' behalf are presented within the financing activities section instead of the operating activities section of the statement of cash flows. We elected the retrospective method for adoption of this update and the change in the statement of cash flows is not material for the years ended December 31, 2016 or 2015. Excess tax benefits were classified as an operating activity within the statement of cash flows on a prospective basis beginning in 2017; as such, prior periods were not adjusted. See Note 2 for additional discussion.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


2. Accounting Standards
Not Yet Adopted
In May 2014 and August 2015, the FASB issued an update that supersedes the existing revenue recognition requirements. This standard includes a five-step revenue recognition model to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. Among other things, the standard requires enhanced disclosures about revenue, provides guidance for transactions that were not previously addressed comprehensively and improves guidance for multiple-element arrangements. This standard is effective for us in the first quarter of 2018 and shall be applied retrospectively to each prior reporting period presented (“full retrospective method”) or with the cumulative effect of initially applying the update recognized at the date of initial application (“modified retrospective method”). We will adopt this new standard in the first quarter of 2018 using the modified retrospective method. The adoption of this ASU will not have a material impact on our consolidated results of operations, financial position or cash flows. However, as a result of this standard we will change our presentation of marketing revenues and marketing expenses from the current gross presentation to a net presentation for a portion of our international contracts. For the years ended December 31, 2017 and 2016, we expect the impact of this change to be a reduction of approximately $130 million and $100 million, respectively, in marketing revenue and expenses in our consolidated results of operations. We will provide the disclosures required by this standard, such as key sources of revenues from transactions with customers, disaggregated revenue information, and significant accounting estimates and judgments, beginning in the first quarter of 2018.
In March 2017, the FASB issued a new accounting standards update that will change how employers that sponsor defined pension and/or other postretirement benefit plans present the net periodic benefit cost in the income statement. Employers will present the service cost component of net periodic benefit cost in the same income statement line item(s) as other employee compensation costs arising from services rendered during the period. Only the service cost component will be eligible for capitalization in assets. We will adopt this standard in the first quarter of 2018 on a retrospective basis, and will reclassify certain amounts from general and administrative expense to the exploration, production and our new other net periodic benefit costs expense categories on our consolidated statements of income.
In August 2016, the FASB issued a new accounting standards update which seeks to reduce the existing diversity in practice in how certain transactions are classified in the statement of cash flows. We will adopt this standard during the first quarter of 2018 on a retrospective basis with no significant impact on our consolidated results of operations, financial position or cash flows.
In November 2016, the FASB issued a new accounting standards update that requires entities to show the changes in the total of cash, cash equivalents and restricted cash in the statement of cash flows. As a result, entities will no longer present transfers between cash and cash equivalents and restricted cash in the statement of cash flows. When cash, cash equivalents, and restricted cash are presented in more than one line item on the balance sheet, the standard requires a reconciliation of the totals in the statement of cash flows to the related captions in the balance sheet. This reconciliation can be presented either on the face of the statement of cash flows or in the notes to the financial statements. We will adopt this standard in the first quarter of 2018 on a retrospective basis and do not expect the adoption of this standard to have a significant impact on our consolidated results of operations, financial position or cash flows.
In February 2017, the FASB issued a new accounting standards update that clarifies the accounting for the sale or transfer of nonfinancial assets and in substance nonfinancial assets to noncustomers, including partial sales. The standard also clarifies that the derecognition of all businesses (except those related to conveyances of oil and gas mineral rights or contracts with customers) should be accounted for in accordance with the derecognition and deconsolidation guidance in Subtopic 810-10. We will adopt this standard in the first quarter of 2018 using the modified retrospective approach with no material impact on our consolidated results of operations, financial position or cash flows.
In January 2017, the FASB issued a new accounting standards update that changes the definition of a business to assist entities with evaluating when a set of transferred assets and activities constitutes a business. The guidance requires an entity to evaluate if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or a group of similar identifiable assets; if so, the set of transferred assets and activities would not represent a business. The guidance also requires a business to include at least one substantive process and narrows the definition of outputs by more closely aligning it with how outputs are described in the new revenue guidance. We will adopt this standard in the first quarter of 2018 on a prospective basis. Since we adopted the standard on a prospective basis, adoption of this standard will not have a significant impact on our consolidated results of operations, financial position or cash flows for prior periods.
In January 2016, the FASB issued an accounting standards update that addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. We plan to adopt this standard in the first quarter of 2018
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


and do not expect the adoption of this standard to have a significant impact on our consolidated results of operations, financial position or cash flows.
In February 2016, the FASB issued a new lease accounting standard, which requires lessees to recognize most leases, including operating leases, on the balance sheet as a right of use asset and lease liability. Short-term leases can continue being accounted for off balance sheet based on a policy election. This standard does not apply to leases to explore for or use minerals, oil, natural gas and similar non-regenerative resources, including the intangible right to explore for those natural resources and rights to use the land in which those natural resources are contained. This standard is effective for us in the first quarter of 20182019 and shall be applied onusing a modified retrospective basis.approach at the beginning of the earliest period presented in the financial statements. Early adoption is permitted. We are evaluatingWhile we will have to recognize a right of use asset and lease liability on the adoption date, we continue to evaluate the provisions of this accounting standards update and assessing the impacteffects it maywill have on our consolidated statementsresults of operations, financial position or cash flows and related disclosures.flows.
In August 2016,2017, the FASB issued a new accounting standards update which seeksthat amends the hedge accounting model to reduceenable entities to hedge certain financial and nonfinancial risk attributes previously not allowed. The amendment also reduces the existing diversity in practice in how certain transactions are classified in the statementoverall complexity of cash flows.documenting, assessing and measuring hedge effectiveness. This standard is effective for us in the first quarter of 2018 and shall be applied on a retrospective basis.2019. Early adoption is permitted.permitted in any interim or annual period. The amendment mandates modified retrospective adoption when accounting for hedge relationships in effect as of the adoption date. We are evaluating the provisions of this accounting standards update, including transition requirements, and are assessing the impact if any, it may have on our results of operations, financial position, or cash flows.
In January 2017, the FASB issued a new accounting standards update that eliminates the requirement to calculate the implied fair value of the goodwill (i.e., Step 2 of goodwill impairment test under the current guidance) to measure a goodwill impairment charge. The standard will require entities to record an impairment charge based on the excess of a reporting unit’s carrying amount over its fair value (i.e., measure the charge based on Step 1 under the current guidance). This standard is effective for us in the first quarter of 2020 and shall be applied on a prospective basis. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. Since we will adopt the standard on a prospective basis, we do not expect an impact on our consolidated statementsresults of operations, financial position or cash flows and related disclosures.for prior periods.
In June 2016, the FASB issued a new accounting standards update that changes the impairment model for trade receivables, net investments in leases, debt securities, loans and certain other instruments. The standard requires the use of a forward-looking "expected loss"“expected loss” model as opposed to the current "incurred loss"“incurred loss” model. This standard is effective for us in the first quarter of 2020 and will be adopted on a modified retrospective basis through a cumulative-effect adjustment to retained earnings as of the beginning of the adoption period. Early adoption is permitted starting January 2019. We are evaluating the provisions of this accounting standards update and assessing the impact, if any, it may have on our consolidated results of operations, financial position or cash flows.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


In March 2016, the FASB issued a new accounting standards update that changes several aspects of accounting for share-based payment transactions, including a requirement to recognize all excess tax benefits and tax deficiencies as income tax expense or benefit in the income statement, classification of awards as either equity or liabilities, and classification on the statement of cash flows. This standard is effective for us in the first quarter of 2017 and varying transition methods (modified retrospective, retrospective or prospective) should be applied to different provisions of the standard. Early adoption is permitted. We will adopt this standard during the first quarter of 2017, we do not believe it will have a material effect on our consolidated results of operations, financial position or cash flows.
In February 2016, the FASB issued a new lease accounting standard, which requires lessees to recognize most leases, including operating leases, on the balance sheet as a right of use asset and lease liability. Short-term leases can continue being accounted for off balance sheet based on a policy election. This standard is effective for us in the first quarter of 2019 and should be applied using a modified retrospective approach at the beginning of the earliest period presented in the financial statements. Early adoption is permitted. We are evaluating the provisions of this accounting standards update and assessing the impact it will have on our consolidated results of operations, financial position or cash flows.
In January 2016, the FASB issued an accounting standards update that addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. This standard is effective for us in the first quarter of 2018. Early adoption is allowed for certain provisions. We do not expect the adoption of this standard to have a significant impact on our consolidated results of operations, financial position or cash flows.
In July 2015, the FASB issued an update that requires an entity to measure inventory at the lower of cost and net realizable value. This excludes inventory measured using LIFO or the retail inventory method. This standard is effective for us in the first quarter of 2017 and will be applied prospectively. Early adoption is permitted. We do not expect the adoption of this standard to have a significant impact on our consolidated results of operations, financial position or cash flows.
In May 2014 and August 2015, the FASB issued an update that supersedes the existing revenue recognition requirements. This standard includes a five-step revenue recognition model to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the company expects to be entitled in exchange for those goods or services. Among other things, the standard requires enhanced disclosures about revenue, provides guidance for transactions that were not previously addressed comprehensively and improves guidance for multiple-element arrangements. This standard is effective for us in the first quarter of 2018 and shall be applied retrospectively to each prior reporting period presented ("full retrospective method") or with the cumulative effect of initially applying the update recognized at the date of initial application ("modified retrospective method"). While early adoption is permitted, we plan to adopt this new standard in the first quarter of 2018 using the modified retrospective method. We continue to assess our contracts that will be subject to this standard and assessing the impact it will have on our consolidated results of operations, financial position or cash flows.
Recently Adopted
In May 2015,March 2016, the FASB issued ana new accounting standards update that removes thechanges several aspects of accounting for share-based payment transactions, including a requirement to categorize withinrecognize all excess tax benefits and tax deficiencies as income tax expense or benefit in the fair value hierarchy all investments for which fair value is measured usingincome statement, classification of awards as either equity or liabilities, and classification on the net asset value per share practical expedient. The amendment also removes certain disclosure requirements regarding all investments that are eligible to be measured using the net asset value per share practical expedient and only requires certain disclosures on those investments for which an entity elects to use the net asset value per share expedient.statement of cash flows. This standard was effective for us in the first quarter of 2016 and was applied2017. The new standard requires a company to make a policy election on a retrospective basis. Thishow it accounts for forfeitures; we elected to continue estimating forfeitures using the same methodology practiced prior to adoption of this standard. See Note 1 for the impact this standard only modifies disclosure requirements; as such, there was no impacthas on the presentation of our consolidated results of operations, financial position or cash flows.statements.
In FebruaryJuly 2015, the FASB issued an amendment to the guidance for determining whetherupdate that requires an entity is a variable interest entity ("VIE"). The standard does not addto measure inventory at the lower of cost or remove any ofnet realizable value. This excludes inventory measured using LIFO or the five characteristics that determine whether an entity is a VIE. However, it does change the manner in which a reporting entity assesses one of the characteristics. In particular, when decision-making over the entity’s most significant activities has been outsourced, the standard changes how a reporting entity assesses if the equity holders at risk lack decision making rights.retail inventory method. This standard was effective for us in the first quarter of 2016. The adoption of this standard did not have a significant impact on our consolidated results of operations, financial position or cash flows.
In August 2014, the FASB issued an update that requires management to assess an entity’s ability to continue as a going concern by incorporating2017, and expanding upon certain principles that are currently in U.S. auditing standards.  This standard was effective for us in the fourth quarter of 2016.applied prospectively. Adoption of this standard did not have a significant impact on our consolidated results of operations, financial position or cash flows.

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


3.
Variable Interest Entities
The owners of the AOSP, in which we hold a 20% undivided interest, contracted with a wholly owned subsidiary of a publicly traded Canadian limited partnership ("Corridor Pipeline") to provide materials transportation capabilities among the Muskeg River and Jackpine mines, the Scotford upgrader and markets in Edmonton, Alberta, Canada. The contract, originally signed in 1999 by a company we acquired, allows each holder of an undivided interest in the AOSP to ship materials in accordance with its undivided interest. Costs under this contract are accrued and recorded on a monthly basis, with a $2 million current liability recorded at December 31, 2016 and 2015. Under this agreement, the AOSP absorbs all of the operating and capital costs of the pipeline. Currently, no third-party shippers use the pipeline. Should shipments be suspended, by choice or due to force majeure, we remain responsible for the portion of the payments related to our undivided interest for all remaining periods. The contract expires in 2029; however, the shippers can extend its term perpetually. This contract qualifies as a variable interest contractual arrangement and the Corridor Pipeline qualifies as a VIE. We hold a variable interest but are not the primary beneficiary because our shipments are only 20% of the total; therefore the Corridor Pipeline is not consolidated by us. Our maximum exposure to loss as a result of our involvement with this VIE is the amount we expect to pay over the contract term, which was $474 million as of December 31, 2016. The liability on our books related to this contract at any given time will reflect amounts due for the immediately previous month’s activity, which is substantially less than the maximum exposure over the contract term. We have not provided financial assistance to Corridor Pipeline and we do not have any guarantees of such assistance in the future.
4.    Income (Loss) per Common Share
Basic income (loss) per share is based on the weighted average number of common shares outstanding. Diluted income per share assumes exercise of stock options in all years, provided the effect is not antidilutive. The per share calculations below exclude 1311 million, 13 million and 413 million stock options in 2017, 2016 2015 and 20142015 that were antidilutive.
 Year Ended December 31,
(In millions, except per share data)2016 2015 2014
Income (loss) from continuing operations$(2,140) $(2,204) $969
Discontinued operations
 
 2,077
Net income (loss)$(2,140) $(2,204) $3,046
      
Weighted average common shares outstanding819
 677
 680
Effect of dilutive securities
 
 3
Weighted average common shares, diluted819
 677
 683
Per basic share: 
  
  
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
Discontinued operations$
 $
 $3.06
Net income (loss)$(2.61) $(3.26) $4.48
Per diluted share:     
Income (loss) from continuing operations$(2.61) $(3.26) $1.42
Discontinued operations$
 $
 $3.04
Net income (loss)$(2.61) $(3.26) $4.46
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements

 Year Ended December 31,
(In millions, except per share data)2017 2016 2015
Income (loss) from continuing operations$(830) $(2,087) $(1,701)
Income (loss) from discontinued operations(4,893) (53) (503)
Net income (loss)$(5,723) $(2,140) $(2,204)
      
Weighted average common shares outstanding850
 819
 677
Per basic share: 
  
  
Income (loss) from continuing operations$(0.97) $(2.55) $(2.51)
Income (loss) from discontinued operations$(5.76) $(0.06) $(0.75)
Net income (loss)$(6.73) $(2.61) $(3.26)
Per diluted share:     
Income (loss) from continuing operations$(0.97) $(2.55) $(2.51)
Income (loss) from discontinued operations$(5.76) $(0.06) $(0.75)
Net income (loss)$(6.73) $(2.61) $(3.26)

5.
4. Acquisitions
2017 - United States E&P
In the fourth quarter of 2017, we closed on our acquisition of additional acreage in the Northern Delaware basin of New Mexico from a private seller for $63 million in cash, subject to post-closing adjustments. We accounted for this transaction as an asset acquisition, allocating the purchase price to unproved property within property, plant and equipment.
In the second quarter of 2017, we closed on our acquisitions of approximately 91,000 net acres in the Permian basin, including over 70,000 net acres in the Northern Delaware basin of New Mexico. On May 1, 2017, we closed on our acquisition with BC Operating, Inc. and other entities for $1.1 billion in cash, subject to post-closing adjustments, to acquire approximately 70,000 net surface acres and current production of approximately 5,000 net barrels of oil equivalent per day. On June 1, 2017, we closed on our acquisition with Black Mountain Oil & Gas and other private sellers for approximately $700 million in cash, subject to post-closing adjustments, to acquire approximately 21,000 net surface acres. The purchase price for these acquisitions was paid with cash on hand. We accounted for these transactions as asset acquisitions, with substantially all of the purchase price allocated to unproved property within property, plant and equipment.
2016 - North AmericaUnited States E&P
On August 1, 2016, we closed on our acquisition of PayRock Energy Holdings, LLC ("PayRock"(“PayRock”), a portfolio company of EnCap Investments, including approximately 61,000 net surface acres in the oil window of the Anadarko Basin STACK play in Oklahoma. The purchase price of $904 million, subject to closing adjustments, was paid with cash on hand. We accounted for this transaction as an asset acquisition, with a majority of the purchase price allocated to unproved property within property, plant and equipment.
2014 -
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


5. Dispositions
Oil Sands Mining Segment
On May 31, 2017 we closed on the sale of our Canadian business, which included our 20% non-operated interest in the AOSP to Shell and Canadian Natural Resources Limited (“CNRL”) for $2.5 billion, excluding closing adjustments. Under the terms of the agreement, $1.8 billion was paid to us upon closing and the remaining proceeds will be paid in the first quarter of 2018. At closing we received two notes receivable for the remaining proceeds, each with a face value of $375 million. We recorded these notes receivable at fair value, see Note 14 for fair value measurements. Our notes receivable are with 10084751 Canada Limited (“Canada Limited”), an affiliate of Shell Canada Limited, and CNRL. The Canada Limited note receivable is guaranteed by Shell Canada Limited and the CNRL note receivable is guaranteed by Toronto Dominion Bank. In the first quarter of 2017, we recorded an after-tax non-cash impairment charge of $4.96 billion primarily related to the property, plant and equipment of our Canadian business. As the effective date of the transaction was January 1, 2017, we recorded a loss on sale of $43 million during the second quarter of 2017 due to second quarter results of operations from our Canadian business that were recorded in our financial statements but transferred to the buyer upon closing.
Our Canadian business is reflected as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for all periods presented. The following table contains select amounts reported in our consolidated statements of income as discontinued operations:
  Year Ended December 31,
(In millions) 2017 2016 2015
Total sales and other revenues and other income $431
 $863
 $908
Net gain (loss) on disposal of assets (43) 
 
Total revenues and other income 388
 863
 908
Costs and expenses:      
Production expenses 254
 601
 715
Exploration expenses 
 7
 347
Depreciation, depletion and amortization 40
 239
 236
Impairments 6,636
 
 31
Other 25
 87
 98
Total costs and expenses 6,955
 934
 1,427
Pretax income (loss) from discontinued operations (6,567) (71) (519)
Provision (benefit) for income taxes (1,674) (18) (16)
Income (loss) from discontinued operations $(4,893) $(53) $(503)
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


The following table presents the carrying value of the major categories of assets and liabilities of our Canadian business reported as discontinued operations and other non-core international assets and liabilities from continuing operations, that are reflected as held for sale on our consolidated balance sheets at December 31, 2017 and December 31, 2016:
  December 31, December 31,
(In millions) 2017 2016
Assets held for sale    
Current assets:    
Cash and cash equivalents $
 $2
Accounts receivables 
 129
Inventories 
 91
Other 
 4
Total current assets held for sale—discontinued operations 
 226
Total current assets held for sale—continuing operations 11
 1
Total current assets held for sale $11
 $227
     
Noncurrent assets:    
Property, plant and equipment, net $
 $8,991
Other 
 106
Total noncurrent assets held for sale—discontinued operations 
 9,097
Total noncurrent assets held for sale—continuing operations 55
 1
Total noncurrent assets held for sale $55
 $9,098
     
Liabilities associated with assets held for sale    
Current liabilities:    
Accounts payable $
 $111
Other 
 10
Total current liabilities held for sale—discontinued operations 
 121
Total current liabilities held for sale—continuing operations 
 
Total current liabilities held for sale $
 $121
     
Noncurrent liabilities:    
Asset retirement obligations $
 $95
Deferred tax liabilities 
 1,669
Other 
 20
Total noncurrent liabilities held for sale—discontinued operations 
 1,784
Total noncurrent liabilities held for sale—continuing operations 2
 7
Total noncurrent liabilities held for sale $2
 $1,791
United States E&P Segment
As disclosed above, we closed on the sale of our Canadian business in May of 2017. This sale included interests in our exploration stage in-situ leases which were included within our historically named North America E&P Segment. See Note 6 for further detail on our segments. These interests have been reflected as discontinued operations and are included within the disclosure above.
In July 2017, we entered into an agreement to sell certain conventional assets in Oklahoma. We closed on the fourth quartersale in September 2017 for proceeds of 2014, we acquired additional acres in the SCOOP, at$25 million, and recognized a costpre-tax gain of $58 million after final settlement adjustments.
In the third quarter of 2014, we acquired acreage in the Oklahoma Resource Basins, at a cost of $68 million after final settlement adjustments.
6. Dispositions
2016 - North America E&P Segment $21 million.
In September 2016, we entered into an agreement to sell certain non-operated CO2 and waterflood assets in West Texas and New Mexico. The sale closed in late October for proceeds of $235 million, and we recognized a total pre-tax gain of $63
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


million. During the third quarter 2016, we sold certain non-operated assets primarily in West Texas and New Mexico to multiple purchasers for combined proceeds of approximately $67 million, and recognized a total pre-tax gain of $55 million.
In April 2016, we announced the sale of our Wyoming upstream and midstream assets. During the second quarter, we received proceeds of approximately $690 million and recorded a pre-tax gain of $266 million with the remaining asset sales closing in November 2016 for proceeds of $155 million, excluding closing adjustments. A pre-tax gain of $38 million was recognized in the fourth quarter 2016.
In March and April 2016, we entered into separate agreements to sell our 10% working interest in the outside-operated Shenandoah discovery in the Gulf of Mexico, operated natural gas assets in the Piceance basin in Colorado and certain undeveloped acreage in West Texas for a combined total of approximately $80 million in proceeds. We closed on certain of the asset sales and recognized a net pre-tax loss on sale of $48 million in 2016, with the remaining asset sales expected to closeclosed in the second quarter2017 with a net pre-tax gain on sale of 2017.
2015 - North America E&P Segment$32 million.
In November 2015, we entered into an agreement to sell our operated producing properties in the greater Ewing Bank area and non-operated producing interests in the Petronius and Neptune fields in the Gulf of Mexico. The transaction closed in December 2015, excluding the Neptune field, for proceeds of $111 million. A $228 million pretax gain was recorded in the fourth quarter of 2015. Assets held for sale in the December 31, 2015 consolidated balance sheet were related to the Neptune field that was pending at that date and included $31 million in total assets and $54 million of total liabilities. The Neptune field transaction closed during the first quarter of 2016 for cash proceeds of $4 million.     
In August 2015, we closed the sale of our East Texas, North Louisiana and Wilburton, Oklahoma natural gas assets for proceeds of $100 million and recorded a pretax loss of $1 million. During the second quarter of 2015, we recorded a non-cash impairment charge of $44 million related to these assets (see Note 15)14).
2015 - International E&P Segment
In the third quarter of 2017, we entered into separate agreements to sell certain non-core properties in our International E&P segment for combined proceeds of $53 million, before closing adjustments. We closed on one of the asset sales in the second half of 2017 and recognized no net pre-tax gain or loss on sale. The remaining asset sale is expected to close during 2018 and is classified as held for sale in the consolidated balance sheet as of December 31, 2017, with total assets of $66 million and total liabilities of $2 million. See Note 10 for further detail on impairment expenses recognized concurrently with these agreements.
In the third quarter of 2015, we entered into agreements to sell our East Africa exploration acreage in Ethiopia and Kenya. A pretax loss of $109 million was recorded in the third quarter of 2015. This transaction closed during the first quarter of 2016.
2014 - North America E&P Segment
In June 2014, we closed the sale of non-core acreage located in the far northwest portion of the Williston Basin for proceeds of $90 million. A pretax loss of $91 million was recorded in the second quarter of 2014.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


2014 - International E&P Segment
In June 2014, we entered into an agreement to sell our Norway business, including the operated Alvheim FPSO, 10 operated licenses and a number of non-operated licenses on the Norwegian Continental Shelf in the North Sea.  The transaction closed in the fourth quarter of 2014 for proceeds of $2.1 billion, before netting $589 million cash transferred to the buyer. A $976 million after-tax gain on the sale of Norway business was recorded in the fourth quarter of 2014. Included in this after-tax gain is a deferred tax benefit reflecting our ability to utilize foreign tax credits that otherwise would have needed a valuation allowance.
Our Norway business is reflected as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for the periods prior to and including 2014. Select amounts reported in discontinued operations were as follows:
(In millions)Year Ended December 31, 2014
Revenues applicable to discontinued operations$1,981
Pretax income from discontinued operations$1,693
Pretax gain on disposition of discontinued operations$1,406
In the first quarter of 2014, we closed the sales of our 10% non-operated working interests in the Production Sharing Contracts and Joint Operating Agreements for Angola Blocks 31 and 32 for aggregate proceeds of approximately $2 billion. A $532 million after-tax gain on the sale of our Angola assets was recorded in 2014. Included in this after-tax gain is a deferred tax benefit reflecting our ability to utilize foreign tax credits that otherwise would have needed a valuation allowance.
Our Angola operations are reflected as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for the periods prior to and including 2014. Select amounts reported in discontinued operations were as follows:
(In millions)December 31, 2014
Revenues applicable to discontinued operations$58
Pretax income from discontinued operations$51
Pretax gain on disposition of discontinued operations$426

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


7.6. Segment Information
We have threetwo reportable operating segments.  Each of these segments is organized and managed based upon both geographic location and the nature of the products and services it offers:offers.
North AmericaUnited States E&P ("N.A.U.S. E&P") – explores for, produces and markets crude oil and condensate, NGLs and natural gas in North America;the United States
International E&P ("Int'l E&P") – explores for, produces and markets crude oil and condensate, NGLs and natural gas outside of North Americathe United States and produces and markets products manufactured from natural gas, such as LNG and methanol, in E.G.; and
Oil Sands Mining (“OSM”) – mines, extracts and transports bitumen from oil sands deposits in Alberta, Canada, and upgrades the bitumen to produce and market synthetic crude oil and vacuum gas oil.
Information regarding assets by segment is not presented because it is not reviewed by the chief operating decision maker (“CODM”).  Segment income (loss) represents income (loss) which excludes certain items not allocated to segments, net of income taxes, attributable to the operating segments. A portion of our corporate and operations support general and administrative costs are not allocated to the operating segments. These unallocated costs primarily consist of employment costs (including pension effects), professional services, facilities and other costs associated with corporate and operations support activities. Additionally, items which affect comparability such as:as gains or losses on dispositions, certain impairments, change in tax expense associated with a tax rate change, changes in our valuation allowance, unrealized gains or losses on derivative instruments, pension settlement losses or other items (as determined by the CODM) are not allocated to operating segments.
As discussed in Note 6,5, we closed on the sale of our Angola assetsCanadian business, which includes our Oil Sands Mining segment and our Norwayexploration stage in-situ leases, in the second quarter of 2017. The Canadian business in 2014, and both areis reflected as discontinued operations and is excluded from the Internationalsegment information in all periods presented. Additionally, we renamed our North America E&P segment.segment to United States E&P segment effective June 30, 2017 in all periods presented. See Note 1 for further information.
Year Ended December 31, 2016  Not Allocated  
Year Ended December 31, 2017 Not Allocated  
(In millions)N.A. E&P Int'l E&P OSM to Segments TotalU.S. E&P Int'l E&P to Segments Total
Sales and other operating revenues$2,375
 $665
 $823
 $(110)
(c) 
$3,753
$3,138
 $1,154
 $(81)
(b) 
$4,211
Marketing revenues135
 105
 38
 
 278
29
 133
 
 162
Total revenues2,510
 770
 861
 (110) 4,031
3,167
 1,287
 (81) 4,373
Income from equity method investments
 175
 
 
 175

 256
 
 256
Net gain on disposal of assets and other income28
 32
 2
 382
(d) 
444
13
 6
 117
(c) 
136
Less:                
Production expenses486
 226
 601
 
 1,313
476
 229
 1
 706
Marketing costs142
 103
 37
 
 282
36
 132
 
 168
Exploration expenses127
 17
 7
 179
(e) 
330
Other operating354
 77
 
 431
Exploration154
 5
 250
(d) 
409
Depreciation, depletion and amortization1,835
 276
 239
 45
 2,395
2,011
 328
 33
 2,372
Impairments20
 
 
 47
(f) 
67
4
 
 225
(e) 
229
Other expenses (a)
422
 78
 33
 462
(g) 
995
Taxes other than income149
 
 17
 2
 168
173
 
 10
 183
General and administrative119
 32
 249
(f) 
400
Net interest and other
 
 
 335
 335

 
 270
(g) 
270
Loss on early extinguishment of debt
 
 51
(h) 
51
Income tax provision (benefit)(228) 49
 (16) 1,100
(h) 
905
1
 372
 3
 376
Segment income (loss) / Net income (loss)$(415) $228
 $(55) $(1,898) $(2,140)
Capital expenditures (b)
$936
 $82
 $33
 $18
 $1,069
Segment income (loss) / Income (loss) from continuing operations$(148) $374
 $(1,056) $(830)
Capital expenditures (a)
$2,081
 $42
 $27
 $2,150
(a)
Includes other operating expenses and general and administrative expenses.
(b) 
Includes accruals.
(c)(b) 
Unrealized loss on commodity derivative instruments.
(c)
Primarily related to sale of certain conventional assets in Oklahoma and Colorado. (See Note 5).
(d)Primarily related to unproved property impairments associated with certain non-core properties within our International E&P segment. (See Note 10).
(e)
Primarily related to proved property impairments associated with certain non-core properties within our International E&P segment. (See Note 10).
(f)
Includes pension settlement loss of $32 million (see Note 17).
(g) Includes a gain of $47 million resulting from the termination of our forward starting interest rate swaps. (See Note 13.)
(h) Primarily related to the make-whole call provisions paid upon redemption of our senior unsecured notes. (See Note 15.)



MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Year Ended December 31, 2016 Not Allocated  
(In millions)U.S. E&P Int'l E&P to Segments Total
Sales and other operating revenues$2,375
 $665
 $(110)
(b) 
$2,930
Marketing revenues135
 105
 
 240
Total revenues2,510
 770
 (110) 3,170
Income (loss) from equity method investments
 175
 
 175
Net gain on disposal of assets and other income28
 32
 382
(c) 
442
Less:       
Production expenses486
 226
 
 712
Marketing costs142
 103
 
 245
Other operating328
 43
 113
(d) 
484
Exploration127
 17
 179
(e) 
323
Depreciation, depletion and amortization1,835
 276
 45
 2,156
Impairments20
 
 47
(f) 
67
Taxes other than income149
 
 2
 151
General and administrative94
 35
 352
(g) 
481
Net interest and other
 
 332
 332
Income tax provision (benefit)(228) 49
 1,102
(h) 
923
Segment income (loss) / Income (loss) from continuing operations$(415) $228
 $(1,900) $(2,087)
Capital expenditures (a)
$936
 $82
 $18
 $1,036
(a)
Includes accruals.
(b)
Unrealized loss on commodity derivative instruments.
(c) 
Primarily related to net gain on disposal of assets (see Note 6)5).
(d)
Includes termination payment on our Gulf of Mexico deepwater drilling rig commitment of $113 million.
(e) Primarily related to impairments associated with decision to not drill remaining Gulf of Mexico undeveloped leases (See Note 13)10).
(f) 
Proved property impairments (see Note 13)10).
(g)  
Includes termination payment on our Gulf of Mexico deepwater drilling rig contract of $113 million and includes pension settlement loss of $103 million (see Note 20) and severance related expenses associated with workforce reductions of $8 million.million (see Note 17).
(h) 
Increased valuation allowance on certain of our deferred tax assets $1,346 million (see Note 9)7).
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Year Ended December 31, 2015  Not Allocated   Not Allocated  
(In millions)N.A. E&P Int'l E&P OSM to Segments TotalU.S. E&P Int'l E&P to Segments Total
Sales and other operating revenues$3,358
 $728
 $815
 $50
(c) 
$4,951
$3,358
 $728
 $50
(b) 
$4,136
Marketing revenues396
 103
 72
 
 571
396
 103
 
 499
Total revenues3,754
 831
 887
 50
 5,522
3,754
 831
 50
 4,635
Income (loss) from equity method investments
 157
 
 (12)
(d) 
145
Income from equity method investments
 157
 (12)
(c) 
145
Net gain on disposal of assets and other income24
 27
 21
 122
(e) 
194
24
 27
 122
(d) 
173
Less:                
Production expenses724
 255
 715
 
 1,694
724
 255
 
 979
Marketing costs401
 99
 69
 
 569
401
 99
 
 500
Exploration expenses362
 101
 
 855
(f) 
1,318
Other operating335
 48
 27
 410
Exploration314
 101
 556
(e) 
971
Depreciation, depletion and amortization2,377
 295
 236
 49
 2,957
2,377
 295
 49
 2,721
Impairments2
 
 5
 745
(g) 
752
2
 
 719
(f) 
721
Other expenses (a)
462
 92
 34
 440
(h) 
1,028
Taxes other than income215
 
 18
 1
 234
215
 
 1
 216
General and administrative127
 44
 417
(g) 
588
Net interest and other
 
 
 267
 267

 
 286
 286
Income tax provision (benefit)(279) 61
 (56) (480)
(i) 
(754)(265) 61
 (534) (738)
Segment income (loss) / Net Income (loss)$(486) $112
 $(113) $(1,717) $(2,204)
Capital expenditures (b)
$2,553
 $368
 $(10) $25
 $2,936
Segment income (loss) / Income (loss) from continuing operations$(452) $112
 $(1,361) $(1,701)
Capital expenditures (a)
$2,553
 $368
 $25
 $2,946
(a)
Includes other operating expenses and general and administrative expenses.
(b) 
Includes accruals.
(c)(b) 
Unrealized gain on commodity derivative instruments.
(d)(c) 
Partial impairment of investment in equity method investee (See Note 15)14).
(e)(d) 
Primarily related to gain on sale of our properties and interests in the Gulf of Mexico, partially offset by the loss on sale of East Africa exploration acreage (see Note 6)5).
(f)(e) Unproved property impairments associated with lower forecasted commodity prices and change in conventional exploration strategy (See Note 13).
(g)
Goodwill impairment (see Note 14) and proved property impairments (see Note 15).
(h)
Includes pension settlement loss of $119 million (see Note 20) and severance related expenses associated with workforce reductions of $55 million.
(i) Includes $135 million of deferred tax expense related to Alberta provincial corporate tax rate increase (see Note 9).

Year Ended December 31, 2014  Not Allocated  
(In millions)N.A. E&P Int'l E&P OSM to Segments Total
Sales and other operating revenues$5,770
 $1,410
 $1,556
 $
 $8,736
Marketing revenues1,839
 219
 52
 
 2,110
Total revenues7,609
 1,629
 1,608
 
 10,846
Income from equity method investments
 424
 
 
 424
Net gain (loss) on disposal of assets and other income23
 57
 4
 (96)
(c) 
(12)
Less:         
Production expenses891
 386
 969
 
 2,246
Marketing costs1,836
 217
 52
 
 2,105
Exploration expenses608
 185
 
 
 793
Depreciation, depletion and amortization2,342
 269
 206
 44
 2,861
Impairments23
 
 
 109
(d) 
132
Other expenses (a)
473
 197
 54
 392
(e) 
1,116
Taxes other than income385
 
 20
 1
 406
Net interest and other
 
 
 238
 238
Income tax provision (benefit)381
 288
 76
 (353) 392
Segment income (loss) / Income from continuing operations$693
 $568
 $235
 $(527) $969
Capital expenditures (b)
$4,698
 $534
 $212
 $51
 $5,495
(a)     Includes other operating expenses and general and administrative expenses.
(b)    Includes accruals.
(c)    Primarily related to the sale of non-core acreage in our North America E&P segment (See Note 6).
(d)    Proved property impairments (See Note 15).
(e)    Includes pension settlement loss of $99 million (See Note 20)10).
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


(f)
Includes goodwill impairment (see Note 12) and proved property impairments (see Note 10).
(g)
Includes pension settlement loss of $119 million (see Note 17) and severance related expenses associated with workforce reductions of $55 million.

Revenues from external customers are attributed to geographic areas based upon selling location. The following summarizes revenues from external customers by geographic area.
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
United States$2,400
 $3,804
 $7,609
$3,086
 $2,400
 $3,804
Canada861
 887
 1,608
Libya(a)
54
 
 244
Equatorial Guinea530
 444
 444
Libya431
 54
 
U.K.289
 263
 380
Other international716
 831
 1,385
37
 9
 7
Total revenues$4,031
 $5,522
 $10,846
$4,373
 $3,170
 $4,635
(a)
See Note 12 for discussion of Libya operations.
In 2016,2017, sales to Irving Oil and Valero Marketing and SupplyVitol and each of their respective affiliates accounted for approximately 17% and 10% of our total revenues. In 2015,2016, sales to Irving OilValero Marketing and Shell OilSupply, Tesoro Petroleum, and Flint Hills Resources and each of their respective affiliates accounted for approximately 13%, 11% and 11%10% of our total revenues. In 2014,2015, sales to Shell Oil and its affiliates accounted for approximately 10% of our total revenues.
The following summarizes revenues by product line were.line.
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Crude oil and condensate$2,605
 $3,963
 $8,170
$3,477
 $2,605
 $3,963
Natural gas liquids198
 203
 371
338
 198
 203
Natural gas356
 464
 693
510
 356
 464
Synthetic crude oil816
 781
 1,525
Other56
 111
 87
48
 11
 5
Total revenues$4,031
 $5,522
 $10,846
$4,373
 $3,170
 $4,635

The following summarizes property, plant and equipment and equity method investments.
December 31,December 31,
(In millions)2016 20152017 2016
United States$14,272
 $15,353
$15,971
 $14,272
Canada8,991
 9,197
Equatorial Guinea1,794
 1,917
1,582
 1,794
Other international1,592
 1,597
959
 1,592
Total long-lived assets$26,649
 $28,064
$18,512
 $17,658

8. Other Items7. Income Taxes
Net interest and otherIncome (loss) before tax expense for continuing operations was:
 Year Ended December 31,
(In millions)2016 2015 2014
Interest:     
Interest income$14
 $9
 $7
Interest expense(402) (358) (309)
Income on interest rate swaps13
 11
 12
Interest capitalized23
 26
 20
Total interest(352) (312) (270)
Other:     
Net foreign currency gain (loss)2
 23
 21
Other15
 22
 11
Total other17
 45
 32
Net interest and other$(335) $(267) $(238)
 Year Ended December 31,
(In millions) 2017 2016 2015
United States $(783) $(1,449) $(2,384)
Foreign 329
 285
 (55)
Total $(454) $(1,164) $(2,439)

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Foreign currency – Aggregate foreign currency gains were included in the consolidated statements of income as follows:
 Year Ended December 31,
(In millions)2016 2015 2014
Net interest and other$2
 $23
 $21
Provision for income taxes(32) (11) (12)
Aggregate foreign currency gains$(30) $12
 $9

9. Income Taxes
Income tax provisions (benefits) for continuing operations were:
Year Ended December 31,Year Ended December 31,
2016 2015 20142017 2016 2015
(In millions)Current Deferred Total Current Deferred Total Current Deferred TotalCurrent Deferred Total Current Deferred Total Current Deferred Total
Federal$2
 $836
 $838
 $(43) $(687) $(730) $15
 $62
 $77
$(32) $41
 $9
 $2
 $836
 $838
 $(41) $(684) $(725)
State and local2
 8
 10
 (8) (18) (26) 8
 (58) (50)(14) 2
 (12) 2
 8
 10
 (8) (18) (26)
Foreign90
 (33) 57
 103
 (101) 2
 281
 84
 365
483
 (104) 379
 91
 (16) 75
 115
 (102) 13
Total$94
 $811
 $905
 $52
 $(806) $(754) $304
 $88
 $392
$437
 $(61) $376
 $95
 $828
 $923
 $66
 $(804) $(738)
A reconciliation of the federal statutory income tax rate applied to income (loss) from continuing operations before income taxes to the provision (benefit) for income taxes follows:
 Year Ended December 31,
 2016 2015 2014
Statutory rate applied to income (loss) from continuing operations before income taxes(35%) (35%) 35 %
Effects of foreign operations, including foreign tax credits5
 (2) (6)
Change in permanent reinvestment assertion
 
 (19)
Adjustments to valuation allowances102
 3
 21
Change in tax law1
 5
 
Goodwill impairment
 4
 
Other
 
 (2)
Effective income tax expense (benefit) rate on continuing operations73 % (25%) 29 %
  Year Ended December 31,
(In millions) 2017 2016 2015
Total pre-tax income (loss) from continuing operations $(454) $(1,164) $(2,439)
Total income tax expense (benefit) $376
 $923
 $(738)
Effective income tax expense (benefit) rate on continuing operations 83% 79% (30)%
       
Income taxes at the statutory tax rate of 35% (a)
 $(159) $(407) $(854)
Effects of foreign operations 140
 47
 (55)
Adjustments to valuation allowances 446
 1,270
 95
State income taxes (19) 9
 (15)
Tax law change (35) 6
 (3)
Goodwill impairment 
 
 94
Other federal tax effects 3
 (2) 
Income tax expense (benefit) on continuing operations $376
 $923
 $(738)
(a) Includes income tax benefits primarily related to our U.S. federal income taxes where we have maintained a full valuation allowance since December 2016.
The effective income tax rate is influenced by a variety of factors including the geographic and functional sources of income and the relative magnitude of these sources of income. The difference between the total provision and the sum of the amounts allocated to segments appears in the "Not Allocated to Segments" column of the tables in Note 7.6.
Effects of foreign operations – The effects of foreign operations increased our tax expense in 2017, 2016, increased our tax benefit inand 2015 and decreased our tax expense in 2014 due to a shift inthe mix of pretax income mix between high and low tax jurisdictions. This increase primarily relates to increased sales volumes in Libya during 2017 where the tax rate is 93.5%. Excluding Libya, the effective tax rates on continuing operations would be an expense of 73%5% in 2017, an expense of 79% in 2016, and a benefit of 25%29% in 2015, and an expense2015.
Adjustments to valuation allowances - Since December 31, 2016, we have maintained a full valuation allowance on our net federal deferred tax assets. In 2017, we recorded a $446 million valuation allowance primarily related to current year activity in the U.S. Included within the $446 million is a $41 million out-of-period adjustment as a result of 27%identifying certain deferred tax assets for which the impact should have been recorded to other comprehensive income, but had been recorded to income from continuing operations in 2014.2016.
Change in permanent reinvestment assertiontax lawOn December 22, 2017, the U.S. enacted the Tax Cuts and Jobs Act (the “Tax Reform Legislation”). Tax Reform Legislation, which is also commonly referred to as “U.S. tax reform”, significantly changes U.S. corporate income tax laws by, among other things, reducing the U.S. corporate income tax rate to 21% starting in 2018, and repeal of the corporate alternative minimum tax (“AMT”), and a one-time deemed repatriation of accumulated foreign earnings. In the fourth quarter of 2017, we remeasured our deferred taxes at 21%, in accordance with U.S. GAAP standards. The impact of the remeasurement on our federal deferred tax assets and liabilities was equally offset by an adjustment to our valuation allowance with no material impact to current year earnings. We have not elected anyrecorded a net benefit of $35 million, classified as a receivable within other noncurrent assets on the consolidated balance sheet, during the fourth quarter of 2017 related to the repeal of the corporate AMT. Although the $35 million net benefit represents what we believe is a reasonable estimate of the impact of the income tax effects of the Act on our foreign earnings toconsolidated financial statements as of December 31, 2017, it should be considered permanently reinvested abroad in 2016. In the second quarter of 2015, we removed our assertion for previously unremitted foreign earnings of approximately $1 billion associated with our Canadian operations. Foreign tax credits associated with these Canadian earnings are sufficient to offset any incremental U.S. tax liabilities, and therefore, no additional net deferred U.S. taxes were recorded. In the second quarter of 2014, we removed our assertion for previously unremitted foreign earnings associated with our U.K. operations to be permanently reinvested outside the U.S.  The U.K. statutory tax rate was in excess of the U.S. statutory tax rate and therefore foreign tax credits associated with these earnings exceeded any incremental U.S. tax liabilities. provisional. We do
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Adjustments to valuation allowances - As a result of the sustained decline in commodity prices wenot expect to pay U.S. federal cash taxes on the deemed repatriation due to an accumulated deficit in foreign earnings for tax purposes.
Once we finalize certain tax positions when we file our 2017 federal tax return, we will be able to conclude whether any further adjustments are required to our net tax position as of December 31, 2017. Any adjustments to these provisional amounts will be reported as a component of income tax expense (benefit) in a cumulative loss positionthe reporting period in early 2017 which constitutes significant negative evidence when assessing the need for a valuation allowance and limits our ability to consider other subjective positive evidence,any such as forecasted projections for taxable income in future years. As such, inadjustments are determined, which will be no later than the fourth quarter of 2016, we increased the valuation allowance against foreign tax credits and other federal deferred tax assets. Additionally, we decreased the valuation allowance on foreign deferred tax assets associated with the disposition of certain foreign operations.
In 2015, we increased the valuation allowance against foreign tax credits because it is more likely than not that we will be unable to realize all U.S. benefits on foreign taxes accrued in 2015. Additionally, in 2015 we increased the valuation allowance on deferred tax assets associated with our foreign operations as a result of pretax losses in certain jurisdictions.
In 2014, we increased the valuation allowance against foreign tax credits as a result of removing the permanent reinvestment assertion on our U.K. operations since the U.K. statutory tax rate is in excess of the U.S. statutory tax rate per discussion above.
Change in tax law – On September 15, 2016, the U.K. government enacted legislation reducing the rate of the Petroleum Revenue Tax from 35% to 0% and reducing the Supplemental Charge Tax from 20% to 10%. As a result of this legislation, we reduced our deferred tax asset by $6 million and recorded a non-cash deferred tax expense in the third quarter of 2016. On June 29, 2015, the Alberta government enacted legislation to increase the provincial corporate tax rate from 10% to 12%. As a result of this legislation, we recorded a non-cash deferred tax expense of $135 million in the second quarter of 2015.2018.
Deferred tax assets and liabilities resulted from the following:
Year Ended December 31,Year Ended December 31,
(In millions)2016 20152017 2016
Deferred tax assets:      
Employee benefits$228
 $260
$111
 $228
Operating loss carryforwards1,065
 563
1,030
 1,065
Capital loss carryforwards4
 17
3
 4
Foreign tax credits4,430
 4,335
611
 4,430
Other credit carryforwards35
 35

 35
Investments in subsidiaries and affiliates91
 17
174
 91
Other88
 73
69
 86
Valuation allowances:   
Federal(4,166) (2,820)
State, net of federal benefit(53) (56)
Foreign(84) (162)
Subtotal1,998
 5,939
Valuation Allowance(926) (4,301)
Total deferred tax assets1,638
 2,262
1,072
 1,638
Deferred tax liabilities:      
Property, plant and equipment3,672
 3,376
1,332
 3,672
Accrued revenue81
 75
Other68
 105
3
 (7)
Total deferred tax liabilities3,740
 3,481
1,416
 3,740
Net deferred tax liabilities$2,102
 $1,219
$344
 $2,102

Foreign Tax Credits - As a result of U.S. tax reform, we have reduced our foreign tax credits at December 31, 2017, which are offset by a corresponding reduction in valuation allowance, by $3,819 million due to the remote likelihood these credits will be utilized before expiration. We have not elected any of our foreign earnings to be permanently reinvested abroad. Additionally due to U.S. tax reform, we do not expect future foreign earnings from operations to be subject to tax in the U.S. The remaining foreign tax credits, which are offset by a valuation allowance, expire in 2022 through 2027.
Operating loss carryforwards - At December 31, 20162017, our operating loss carryforwards before valuation allowance includes $1.8 billion$898 million from the U.S. that expire in 2035 and 2036.2035-2037. Foreign operating loss carryforwards include $975$13 million from Canada that begin to expire in 2029 through 2036, $332 million from the Kurdistan Region of Iraq that expire in 2017 through 2021, $83 million from Libya that expires in 2026 and $8 million from E.G. that expire in 2017 through 2021.2018. State operating loss carryforwards of $1,359$119 million expire in 20172018 through 2036. Foreign tax credit carryforwards of $3,906 million expire in 2022 through 2026.2037.
Valuation allowancesWe consider whether it is more likely than not that some portion or allAt December 31, 2017, we reflect a valuation allowance in our consolidated balance sheet of $926 million against our net deferred tax assets will not be realized. In the event it is more likely than not that some portion or all of our deferred taxes will not be realized, such assets are reduced by a valuation allowance.in various jurisdictions in which we operate. The estimated realizability of the benefit of our deferred tax asset is assessed considering a preponderance of evidence. This assessment requires analysis of all available positive and negative evidence. Positive evidence includes reversals of temporary differences, forecasts of future taxable income, assessment of future business assumptions and applicable tax planning strategies. Negative evidence includes losses in recent years as well as the forecasts of future income (loss) in the realizable period.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


We expect to be in a cumulative loss position in early 2017 which constitutes significant negative evidence asreduction primarily related to the future realizabilityreduction of the value of our deferred tax assets. As a result, we are limited in our ability to consider forecasts for taxable income in future years in connection with our assessment of the realizability of our foreign tax credits in the U.S. In 2016 and other federal deferred tax assets. Additionally, we considered the reversals of existing deferred tax assets and liabilities related to temporary differences between the book and tax basis of our assets and liabilities and concluded that it is more likely than not that a portion of our deferred tax assets would not be realized. Therefore,2015, we increased our valuation allowance on our federal deferred tax assets by $1,346$1,268 million in 2016 related to U.S. benefits on foreign taxes and other federal deferred tax assets. If objective negative evidence in the form of cumulative losses is no longer present and additional weight is given to subjective evidence such as forecasted projections of taxable income in future years, we would adjust the amount of the federal deferred tax assets considered realizable and reduce the provision for income taxes in the period of adjustment.
Federal valuation allowances increased $45$99 million in 2015 related to U.S. benefits on foreign taxes accrued in 2015. Federal valuation allowances decreased $222 million in 2014 primarily due to the sale of our Norway and Angola businesses.
Foreign valuation allowances decreased $78 million in 2016 primarily due to the disposal of our Ethiopia, Kenya, and certain E.G. assets. Foreign valuation allowances increased $54 million in 2015 primarily due to deferred tax assets generated in the Kurdistan Region of Iraq, E.G. and Gabon. Foreign valuation allowances decreased $41 million in 2014 primarily due to the disposal of our Angolan assets.respectively.
Net deferred tax liabilities were classified in the consolidated balance sheets as follows:
December 31,December 31,
(In millions)2016
20152017 2016
Assets:



 
Other current assets$

$
Other noncurrent assets336

1,222
$489
 $336
Liabilities:



 
Other current liabilities


Noncurrent deferred tax liabilities2,438

2,441
833
 769
Noncurrent liabilities held for sale
 1,669
Net deferred tax liabilities$2,102

$1,219
$344
 $2,102
We are continuously undergoing examination of our U.S. federal income tax returns by the IRS. Such audits have been completed through the 2014 tax year, with the exception of 2010-11,2010-11. During the third quarter of 2017, we received a
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


partnership adjustment notification related to the 2010 and 2011 tax years, for which are currently under IRS appeals.we have filed a Tax Court Petition in the fourth quarter of 2017. We believe adequate provision has been made for federal income taxes and interest which may become payable for years not yet settled. See Note 24 for further detail. Further, we are routinely involved in U.S. state income tax audits and foreign jurisdiction tax audits. We believe all other audits will be resolved within the amounts paid and/or provided for these liabilities.

As of December 31, 20162017, our income tax returns remain subject to examination in the following major tax jurisdictions for the tax years indicated:
United States(a)
2008-2015
Canada2010-20152008-2016
Equatorial Guinea2007-20152007-2016
Libya2012-20152012-2016
United Kingdom2008-20152008-2016
(a) 
Includes federal and state jurisdictions.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


The following table summarizes the activity in unrecognized tax benefits:
(In millions)2016 2015 20142017 2016 2015
Beginning balance$65
 $80
 $146
$66
 $65
 $80
Additions for tax positions related to the current year
 
 
Additions for tax positions of prior years6
 1
 11
83
 6
 1
Reductions for tax positions of prior years(5) 
 (68)(3) (5) 
Settlements
 (7) (9)(20) 
 (7)
Statute of limitations
 (9) 

 
 (9)
Ending balance$66
 $65
 $80
$126
 $66
 $65
If the unrecognized tax benefits as of December 31, 20162017 were recognized, $25$10 million would affect our effective income tax rate. As of December 31, 2016,2017, there are $20$83 million uncertain tax positions for which it is reasonably possible that the amount wouldcould significantly increase or decreasechange during the next twelve months. If this were to significantly change, we estimate that any revisions to current and deferred tax liabilities would have no cumulative adverse earnings impact on our consolidated results of operations.
The U.K. tax authorities have challenged the timing of deductibility for certain Brae area decommissioning costs. In the fourth quarter of 2017, we received an adverse ruling from the U.K. first-tier tax tribunal. As a result of the adverse ruling, in the fourth quarter of 2017 we established an uncertain tax position. We have appealed the ruling, but were required to pay the disputed tax amount and associated interest in order to pursue the appeal. The payment of the disputed tax and interest, approximately $108 million, is not considered a settlement of the tax dispute with the U.K. tax authorities. If we prevail in appeals, we will be refunded the tax and interest paid, however, if we do not prevail no further material cash payments are expected due to the initial payment required to appeal the adverse ruling. See Note 24 for further detail.
Interest and penalties are recorded as part of the tax provision and were $1$2 million, $1 million and $6$1 million related to unrecognized tax benefits in 2017, 2016 2015 and 2014.2015. As of December 31, 2017 and 2016, and 2015, $15$25 million and $14$15 million of interest and penalties were accrued related to income taxes.
Pretax income (loss) from continuing operations included amounts attributable to foreign sources of $204 million, $(654) million and $1,180 million in 2016, 2015 and 2014.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


10.
8. Inventories
Crude oil and natural gas and bitumen are recorded at weighted average cost and carried at the lower of cost or marketnet realizable value. Supplies and other items consist principally of tubular goods and equipment which are valued at weighted average cost and reviewed periodically for obsolescence or impairment when market conditions indicate.
December 31,December 31,
(In millions)2016 20152017 2016
Crude oil, natural gas and bitumen$31
 $35
Crude oil and natural gas$9
 $6
Supplies and other items196
 278
117
 130
Inventories at cost$227
 $313
Inventories$126
 $136

11. Equity Method Investments and Related Party Transactions
During 2016, 2015 and 2014 only our equity method investees were considered related parties and they included:
EGHoldings, in which we have a 60% noncontrolling interest. EGHoldings is engaged in LNG production activity.
Alba Plant LLC, in which we have a 52% noncontrolling interest. Alba Plant LLC processes LPG.
AMPCO, in which we have a 45% interest. AMPCO is engaged in methanol production activity.
Our equity method investments are summarized in the following table:
 Ownership as of December 31,
(In millions)December 31, 2016 2016 2015
EGHoldings60% $550
 $603
Alba Plant LLC52% 215
 230
AMPCO45% 165
 169
Other investments  1
 1
Total  $931
 $1,003
Dividends and partnership distributions received from equity method investees (excluding distributions that represented a return of capital previously contributed) were $192 million in 2016, $178 million in 2015 and $451 million in 2014.
Summarized financial information for equity method investees is as follows:
(In millions)2016 2015 2014
Income data – year:     
Revenues and other income$770
 $769
 $1,349
Income from operations346
 313
 826
Net income313
 280
 728
Balance sheet data – December 31:     
Current assets$525
 $467
  
Noncurrent assets1,173
 1,317
  
Current liabilities218
 211
  
Noncurrent liabilities47
 41
  
Revenues from related parties were $54 million, $51 million and $56 million in 2016, 2015 and 2014, with the majority related to EGHoldings in all years. Purchases from related parties were $103 million, $207 million and $207 million in 2016, 2015 and 2014 with the majority related to Alba Plant LLC in all years.
Current receivables from related parties at December 31, 2016 and 2015, were $23 million, and $29 million. Payables to related parties were $11 million and $5 million at December 31, 2016 and 2015, with the majority related to Alba Plant LLC.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


12.9. Property, Plant and Equipment
December 31,December 31,
(In millions)2016 20152017 2016
North America E&P$14,158
 $15,226
United States E&P$15,867
 $14,158
International E&P2,470
 2,533
1,710
 2,470
Oil Sands Mining8,991
 9,197
Corporate99
 105
88
 99
Net property, plant and equipment$25,718
 $27,061
$17,665
 $16,727

Our Libya operations have been interrupted in recent years due to civil unrest.  On September 14, 2016, Force Majeure was lifted and production resumed in October 2016 at our Waha concession.  During December 2016, liftings resumed from the Es-Sider crude oil terminal.
As ofAt December 31, 2017, 2016 our net property, plant and equipment investment in Libya is approximately $768 million, and2015 we had total proved reserves (unaudited) in Libya are 206 mmboe. We and our partners in the Waha concessions continue to assess the situation and the condition of our assets in Libya. Our periodic assessment of the carrying value of our net property, plant and equipment in Libya specifically considers the net investment in the assets, the duration of our concessions and the reserves anticipated to be recoverable in future periods.  The undiscounted cash flows related to our Libya assets continue to exceed the carrying value of $768 million by a significant amount.
Deferreddeferred exploratory well costs were as follows:
December 31,December 31,
(In millions)2016 2015 20142017 2016 2015
Amounts capitalized less than one year after completion of drilling$131
 $352
 $484
$263
 $131
 $352
Amounts capitalized greater than one year after completion of drilling118
 85
 126
32
 118
 85
Total deferred exploratory well costs$249
 $437
 $610
$295
 $249
 $437
Number of projects with costs capitalized greater than one year after          
completion of drilling3
 2
 3
1
 3
 2
  
          
(In millions)2016 2015 20142017 2016 2015
Beginning balance$437
 $610
 $793
$249
 $437
 $573
Additions299
 610
 647
212
 299
 610
Charges to expense(a)(23) (148) (45)(64) (23) (111)
Transfers to development(388) (635) (579)(102) (388) (635)
Dispositions(a)(b)
(76) 
 (206)
 (76) 
Ending balance$249
 $437
 $610
$295
 $249
 $437
(a) 
Includes $64 million in exploratory well costs being expensed as a result of our agreement to sell Diaba License G4-223 in the Republic of Gabon in August of 2017. See Note 10 for further detail.
(b)
Includes sale of GOM assets in 2016, and the sale of Angola assets and Norway business in 2014.2016.

Exploratory well costs capitalized greater than one year after completion of drilling are associated with one project in E.G. with costs of $32 million as of December 31, 2016 are summarized by geographical area below:
(In millions)
  
Gabon$64
E.G.54
Total$118
Well costs that have been suspended for longer than one year are associated with three projects.2017. Management believes these projectsthis project with suspended exploratory drilling costs exhibit sufficient quantities of hydrocarbons to justify potential development based on current plans.
Gabon - The Diaba-1B well reached total depth For this project in the third quarter of 2013. Additional 3D seismic data was acquired in late 2014 in the western part of the block, and depth processing continued through the third quarter of 2016.  We continue to utilize this data to facilitate evaluation of additional resource potential on the offshore Diaba License to support decisions regarding the exploration program.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


E.G. – The Corona well on Block D offshore E.G. was drilled in 2004, and we acquired an additional interest in the well in 2012. We plan to develop Block D through a unitization with the Alba field. Negotiations have been substantially completed and we are awaiting approval from the host government.
Drilling, drilling was completed on the Rodo well in Alba Block Sub Area B, offshore E. G. in the first quarter of 2015, and we have since completed a seismic feasibility study. In early 2017, we received approval for and proceeded to perform a seismic reprocessing program. After completion of this program and after completion,we will evaluate drilling opportunities within Sub Area B.

13.10. Impairments and Exploration Expenses
Impairments
As a result of our announced disposition of our Canadian business in the first quarter of 2017, we recorded a pre-tax non-cash impairment charge of $6.6 billion primarily related to property, plant and equipment. This impairment in our Canadian business is reflected as discontinued operations in the consolidated statements of income and the consolidated statements of cash flows for all periods presented
The following table summarizes impairment charges of proved properties:
Year Ended December 31,Year Ended December 31,
(in millions)2016 2015 20142017 2016 2015
Total impairments$67
 $752
 $132
$229
 $67
 $721
2017 - Impairments were primarily a result of lower forecasted long-term commodity prices and the anticipated sales of certain non-core proved properties in our International E&P segment of $136 million. Additionally, included in proved property impairments was $89 million relating to the Gulf of Mexico and certain conventional Oklahoma assets primarily as a result of lower forecasted long-term commodity prices.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


2016 - Impairments of $67 million consisted primarily of proved properties in Oklahoma and the Gulf of Mexico as a result of lower forecasted commodity prices and revisions to estimated abandonment costs.
2015 - Impairments included $340 million for the goodwill impairment of the North AmericaUnited States E&P reporting unit, and $335 million related to proved properties (primarily in Colorado and the Gulf of Mexico) as a result of lower forecasted commodity prices, and $44 million associated with our disposition of natural gas assets in East Texas, North Louisiana and Wilburton, Oklahoma.
2014 - Impairments of $132 million consisted primarily of proved properties in the Gulf of Mexico, Texas and North Dakota as a result of revisions to estimated abandonment costs and lower forecasted commodity prices.
See Note 76 for relevant detail regarding segment presentation, Note 1412 for further detail regarding the goodwill impairment and Note 1514 for fair value measurements related to impairments of proved properties and long-lived assets.
Exploration expense
The following table summarizes the components of exploration expenses:
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Exploration Expenses          
Unproved property impairments$195
 $964
 $306
$246
 $195
 $655
Dry well costs32
 250
 317
77
 25
 212
Geological and geophysical5
 31
 85
25
 5
 31
Other98
 73
 85
61
 98
 73
Total exploration expenses$330
 $1,318
 $793
$409
 $323
 $971
Unproved property impairments and dry well costs
2017 - As a result of lower forecasted long-term commodity prices and the anticipated sales of certain non-core properties in our International E&P segment, we recorded a non-cash charge of $159 million comprised of $95 million in unproved property impairments; and $64 million in dry well costs related to our Diaba License G4-223 in the Republic of Gabon. Also, because of our decision not to develop the Tchicuate offshore Block in the Republic of Gabon, we recorded a non-cash impairment charge of $43 million to unproved property.
2016 - PrimarilyUnproved property impairments recorded of $195 million were primarily a result of our decision to not drill any of our remaining Gulf of Mexico undeveloped leases and also includes certain other unproved properties in North America.the United States. Lower dry well expense was a result of the strategic decision to transition out of our conventional exploration program during 2015.
2015- Primarily due to changes in our conventional exploration strategy (Gulf of Mexico, Canadian in-situ assets and Harir block in the Kurdistan Region of Iraq), relinquishment of certain properties in the Gulf of Mexico, the operated Solomon exploration well in the Gulf of Mexico and our unproved property in Colorado as a result of the proved property impairment mentioned above. Dry well costs include the operated Solomon exploration well in the Gulf of Mexico, and our operated Sodalita West #1 exploratory well in E.G.
2014 - Primarily consists of Eagle Ford and Bakken leases that either expired or we decided not to drill or extend.

See Note 76 for relevant detail regarding segment presentation of unproved property impairments.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Dry well11. Asset Retirement Obligations
Asset retirement obligations primarily consist of estimated costs to remove, dismantle and restore land or seabed at the end of oil and gas production operations. Changes in asset retirement obligations were as follows:
 For Year Ended December 31,
(In millions)2017 2016
Beginning balance$1,652
 $1,544
Incurred liabilities, including acquisitions25
 14
Settled liabilities, including dispositions(50) (74)
Accretion expense (included in depreciation, depletion and amortization)85
 79
Revisions of estimates(227) 96
Held for sale(2) (7)
Ending balance$1,483
 $1,652
2017
2016Settled liabilities - Lower dryinclude dispositions, primarily related to the sale of certain conventional assets in Oklahoma as well expense as a result of the strategic decision to transition out of our conventional exploration programretirements in the previous year.U.K. and the Gulf of Mexico.
2015Revisions of estimates - Includeswere primarily due to changes in U.K. estimated costs as well as timing of abandonment activities in the operated Solomon explorationU.K.
Ending balance includes $55 million classified as short-term at December 31, 2017.
2016
Settled liabilities include dispositions, primarily related to the Gulf of Mexico and Wyoming as well as retirements in the Gulf of Mexico, our operated Sodalita West #1 exploratory well in E.G. and suspended well costs related our Canadian in-situ assets at Birchwood.Mexico.
2014Revisions of estimates - Includes the operated Key Largowere primarily due to changes in timing of abandonment activities as well outside-operated Perseus well and the outside-operated second Shenandoah appraisal well, all of which are locatedas changes in cost estimated in the Gulf of Mexico. In addition, 2014 alsoU.K.
Ending balance includes our exploration programs in the Kurdistan Region of Iraq, Ethiopia and Kenya.$50 million classified as short-term at December 31, 2016.

14.12. Goodwill
Goodwill is tested for impairment on an annual basis, in April of each year, or between annual tests when events or changes in circumstances indicate the fair value of a reporting unit with goodwill may have been reduced below its carrying value. Goodwill is tested for impairment at the reporting unit level. Our reporting units are the same as our reporting segments, of which only International E&P includes goodwill. We estimatedestimate the fair valuesvalue of theour International E&P reporting unit using a combination of market and income approaches. The market approach referenced observable inputs specific to us and our industry, such as the price of our common equity, our enterprise value, and valuation multiples of us and our peers from the investor analyst community. The income approach utilized discounted cash flows, which were based on forecasted assumptions. Key assumptions to the income approach include future liquid hydrocarbon and natural gas pricing, estimated quantities of liquid hydrocarbonhydrocarbons and natural gas proved and probable reserves, estimated timing of production, discount rates, future capital requirements, operating expenses and tax rates. The assumptions used in the income approach are consistent with those that management uses to make business decisions. These valuation methodologies represent Level 3 fair value measurements. We performed our annual impairment test in the second quarter of 2017 and concluded no impairment was required. As of the date of our last impairment assessment, the fair value of our International E&P reporting unit exceeded its book value by over 40%. We believe the estimates and assumptions used in our impairment assessments are reasonable and based on available market information, but variations in such assumptions could result in materially different calculations of fair value and determinations of whether or not an impairment is indicated.
We performed our annual impairment tests in April of 2016, 2015 and 2014 and no impairment was required. As of the date of our last impairment assessment, the fair value of our International E&P reporting unit exceeded its book value of $115 million by 26%. Subsequent
MARATHON OIL CORPORATION
Notes to our goodwill impairment test in April 2015, triggering events (downward revisions to forecasted commodity price assumptions and sustained price declines in our common stock) required us to reassess our goodwill for impairment as of December 31, 2015. We recorded an impairment of goodwill for the North America E&P reporting unit during the fourth quarter of 2015.Consolidated Financial Statements


The table below displays the allocated beginning goodwill balances by segment along with changes in the carrying amount of goodwill for 20162017 and 2015:2016:
(In millions)N.A. E&P Int'l E&P OSM TotalU.S. E&P Int'l E&P Total
2015       
Beginning balance, gross$344
 $115
 $1,412
 $1,871
Less: accumulated impairments
 
 (1,412) (1,412)
Beginning balance, net344
 115
 
 459
Dispositions(4) 
 
 (4)
Impairment(340) 
 
 (340)
Ending balance, net$
 $115
 $
 $115
2016            
Beginning balance, gross$
 $115
 $1,412
 $1,527
$
 $115
 $115
Less: accumulated impairments
 
 (1,412) (1,412)
 
 
Beginning balance, net
 115
 
 115

 115
 115
Dispositions
 
 
 

 
 
Impairment
 
 
 

 
 
Ending balance, net$
 $115
 $
 $115
$
 $115
 $115
2017     
Beginning balance, gross$
 $115
 $115
Less: accumulated impairments
 
 
Beginning balance, net
 115
 115
Dispositions
 
 
Impairment
 
 
Ending balance, net$
 $115
 $115

13. Derivatives
For further information regarding the fair value measurement of derivative instruments see Note 14. See Note 1 for discussion of the types of derivatives we use and the reasons for them. All of our commodity derivatives and historical interest rate derivatives are subject to enforceable master netting arrangements or similar agreements under which we may report net amounts. The following tables present the gross fair values of derivative instruments and the reported net amounts along with where they appear on the consolidated balance sheets.
 December 31, 2017  
(In millions)Asset Liability Net Asset Balance Sheet Location
Not Designated as Hedges       
     Commodity$
 $138
 $(138) Other current liabilities
     Commodity
 2
 (2) Deferred credits and other liabilities
Total Not Designated as Hedges$
 $140
 $(140)  
     Total$
 $140
 $(140)  
 December 31, 2016  
(In millions)Asset Liability Net Asset Balance Sheet Location
Fair Value Hedges       
     Interest rate$3
 $
 $3
 Other current assets
     Interest rate1
 
 1
 Other noncurrent assets
Cash Flow Hedges       
     Interest rate$64
 $
 $64
 Other noncurrent assets
Total Designated Hedges$68
 $
 $68
  
        
Not Designated as Hedges       
     Commodity$
 $60
 $(60) Other current liabilities
Total Not Designated as Hedges$
 $60
 $(60)  
     Total$68
 $60
 $8
  

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


15.Derivatives Designated as Fair Value Hedges
During the third quarter of 2017, we terminated all of our interest rate swaps designated as fair value hedges. The pretax effects of derivative instruments designated as hedges of fair value in our consolidated statements of income has a gross impact that is not material to net interest and other in all periods presented. Additionally, there is no ineffectiveness related to fair value hedges in all periods presented.
The following table presents, by maturity date, information about our interest rate swap agreements, including the weighted average, London Interbank Offer Rate (“LIBOR”) based, floating rate.
 December 31, 2017 December 31, 2016
 Aggregate Notional AmountWeighted Average, LIBOR-Based, Aggregate Notional AmountWeighted Average, LIBOR-Based,
Maturity Dates(in millions)Floating Rate (in millions)Floating Rate
October 1, 2017$
% $600
5.10%
March 15, 2018$
% $300
5.04%
The pretax effect of derivative instruments designated as hedges of fair value in our consolidated statements of income is summarized in the table below. There is no ineffectiveness related to the historical fair value hedges.
  Gain (Loss)
  Year Ended December 31,
(In millions)Income Statement Location2017 2016 2015
Derivative      
Interest rateNet interest and other$
 $(4) $
Hedged Item  
  
  
DebtNet interest and other$
 $4
 $

Derivatives Not Designated as Hedges
Interest Rate Swaps
During the third quarter of 2016, we entered into forward starting interest rate swaps to hedge the variations in cash flows related to fluctuations in long term interest rates from debt that were probable to be refinanced by us in 2018, specifically interest rate risk associated with future changes in the benchmark treasury rate. We designated these derivative instruments as cash flow hedges. During the second quarter of 2017, we de-designated the forward starting interest rate swaps previously designated as cash flow hedges. In the third quarter of 2017, the forecasted transaction consummated and we issued $1 billion in senior unsecured notes. See Note 15 for further detail. As a result, we terminated our forward starting interest rate swaps receiving proceeds of $54 million. We recognized a gain of $47 million, related to deferred gains reclassified from accumulated other comprehensive income, in net interest and other during 2017.
The following table presents, by maturity date, information about our terminated forward starting interest rate swap agreements, including the rate.
 December 31, 2017 December 31, 2016
 Aggregate Notional AmountWeighted Average, LIBOR Aggregate Notional AmountWeighted Average, LIBOR
Maturity Dates(in millions)Fixed Rate (in millions)Fixed Rate
March 15, 2018$
% $750
1.57%
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


The following table sets forth the net impact of the terminated forward starting interest rate swap derivatives de-designated as cash flow hedges on other comprehensive income (loss).
  Year Ended December 31,
(In millions) 2017 2016 2015
Interest Rate Swaps      
  Beginning balance $60
 $
 $
Change in fair value recognized in other comprehensive income (13) 64
 
Reclassification from other comprehensive income (47) (4) 
  Ending balance $
 $60
 $
Commodity Derivatives
We have entered into multiple crude oil and natural gas derivatives indexed to NYMEX WTI and Henry Hub related to a portion of our forecasted United States E&P sales through 2019. These commodity derivatives consist of three-way collars, swaps, and basis swaps. Three-way collars consist of a sold call (ceiling), a purchased put (floor) and a sold put. The ceiling price is the maximum we will receive for the contract volumes, the floor is the minimum price we will receive, unless the market price falls below the sold put strike price. In this case, we receive the NYMEX WTI/Henry Hub price plus the difference between the floor and the sold put price. These commodity derivatives were not designated as hedges. The following table sets forth outstanding derivative contracts as of December 31, 2017 and the weighted average prices for those contracts:
Crude Oil
 2018 2019
 First Quarter Second Quarter Third Quarter Fourth Quarter First Quarter Second Quarter
Three-Way Collars (a)
           
Volume (Bbls/day)85,000 85,000 85,000 85,000 10,000 10,000
Weighted average price per Bbl:           
Ceiling$56.38 $56.38 $56.96 $56.96 $60.00 $60.00
Floor$51.65 $51.65 $51.53 $51.53 $55.00 $55.00
Sold put$45.00 $45.00 $44.65 $44.65 $47.00 $47.00
Swaps           
Volume (Bbls/day)20,000 20,000    
Weighted average price per Bbl$55.12 $55.12 $— $— $— $—
Basis Swaps (b)
           
Volume (Bbls/day)5,000 5,000 10,000 10,000  
Weighted average price per Bbl$(0.60) $(0.60) $(0.67) $(0.67) $— $—
(a)
Between January 1, 2018 and February 12, 2018, we entered into 10,000 Bbls/day of three-way collars for July - December 2018 with an average ceiling price of $63.51, a floor price of $57.00, and a sold put price of $50.00 and 20,000 Bbls/day of three-way collars for January - June 2019 with an average ceiling price of $67.92, a floor price of $53.50, and a sold put price of $46.50.
(b)
The basis differential price is between WTI Midland and WTI Cushing.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Natural Gas
 2018
 First QuarterSecond QuarterThird QuarterFourth Quarter
Three-Way Collars    
Volume (MMBtu/day)200,000160,000160,000160,000
Weighted average price per MMBtu    
Ceiling$3.79$3.61$3.61$3.61
Floor$3.08$3.00$3.00$3.00
Sold put$2.55$2.50$2.50$2.50

The mark-to-market impact and settlement of these commodity derivative instruments appears in sales and other operating revenues in our consolidated statements of income for the years ended December 31, 2017, 2016, and 2015. The December 31, 2017, 2016, and 2015 impact was a net loss of $36 million, a net loss of $66 million, and a net gain of $128 million, respectively. Net settlements of commodity derivative instruments for the years ended December 31, 2017, 2016, and 2015 were gains of $45 million, $44 million, and $78 million, respectively.
14. Fair Value Measurements
Fair values – Recurring
The following tablestables' present assets and liabilities accounted for at fair value on a recurring basis by hierarchy level.
December 31, 2016December 31, 2017
(In millions)Level 1 Level 2 Level 3 TotalLevel 1 Level 2 Level 3 Total
Derivative instruments, assets              
Commodity (a)
$
 $
 $
 $
Interest rate
 68
 
 68

 
 
 
Derivative instruments, assets$
 $68
 $
 $68
$
 $
 $
 $
Derivative instruments, liabilities              
Commodity$
 $60
 $
 $60
Commodity (a)
$(20) $(120) $
 $(140)
Derivative instruments, liabilities$
 $60
 $
 $60
$(20) $(120) $
 $(140)
              
December 31, 2015December 31, 2016
(In millions)Level 1 Level 2 Level 3 TotalLevel 1 Level 2 Level 3 Total
Derivative instruments, assets              
Commodity (a)
$
 $51
 $
 $51
Interest rate$
 $8
 $
 $8
$
 $68
 $
 $68
Derivative instruments, assets$
 $59
 $
 $59
$
 $68
 $
 $68
Derivative instruments, liabilities              
Commodity (a)
$
 $1
 $
 $1
$
 $60
 $
 $60
Derivative instruments, liabilities$
 $1
 $
 $1
$
 $60
 $
 $60
(a) Derivative instruments are recorded on a net basis in our balance sheet (see Note 16)13).
Commodity derivatives include three-way collars, call optionsswaps, and basis swaps. These instruments are measured at fair value using either a Black-Scholes or a modified Black-Scholes Model. InputsFor swaps and basis swaps, inputs to the models include commodity prices and interest rates and are categorized as Level 1 because all assumptions and inputs are observable in active markets throughout the term of the instruments. For three-way collars, inputs to the models include commodity prices, interest rates, and implied volatility and are categorized as Level 2 because predominantly all assumptions and inputs are observable in active markets throughout the term of the instruments.
BothHistorically, both our interest rate swaps and forward starting interest rate swaps are measured at fair value with a market approach using actionable broker quotes, which are Level 2 inputs. See Note 1613 for additional discussion of the types of derivative instruments we use.  
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Fair values – Nonrecurring
The following table shows the values of assets, by major category, measured at fair value on a nonrecurring basis in periods subsequent to their initial recognition.
2016 2015 20142017 2016 2015
(In millions)Fair Value Impairment Fair Value Impairment Fair Value ImpairmentFair Value Impairment Fair Value Impairment Fair Value Impairment
Long-lived assets held for use$15
 $67
 $56
 $412
 $43
 $132
$179
 $229
 $15
 $67
 $56
 $386
Long-lived assets held for use that were impaired are discussed below. The fair values, of eachunless otherwise noted, were measured using an income approach based upon internal estimates of future production levels, prices and discount rate, all of which are Level 3 inputs.  Inputs to the fair value measurement include reserve and production estimates made by our reservoir engineers, estimated future commodity prices adjusted for quality and location differentials and forecasted operating expenses for the remaining estimated life of the reservoir.
North AmericaUnited States E&P
In the third quarter of 2017, impairments of $65 million were recorded consisting of certain proved properties in the Gulf of Mexico as a result of lower forecasted long-term commodity prices, to an aggregate fair value of $66 million.
In the third quarter of 2016, impairments of $47 million were recorded consisting primarily of conventional non-core proved properties in Oklahoma as a result of lower forecasted long-term commodity prices, to an aggregate fair value of $15 million. During the fourth quarter of 2016, we recorded an impairment of $17 million as a result of abandonment cost revisions related to the Ozona development in the Gulf of Mexico which ceased productionproductions in 2013.
In the third quarter of 2015, impairments of $333 million were recorded primarily related to certain producing assets in Colorado and the Gulf of Mexico as a result of lower forecasted commodity prices, to an aggregate fair value of $41 million.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


During the second quarter of 2015, we recorded an impairment charge of $44 million related to East Texas, North Louisiana and Wilburton, Oklahoma natural gas assets as a result of the anticipated sale. The fair values were measured using a probability weighted income approach based on both the anticipated sale price and held-for-use model.
International E&P
In the third quarter of 2014,2017, we recorded proved property impairments of $53 million were recorded to Gulf of Mexico properties as a result of estimated abandonment cost and other revisions, to an aggregate fair value of $19 million. In addition, two fields were impaired a total of $47$136 million, to an aggregate fair value of $24$103 million, on certain non-core properties in our International E&P segment primarily due to lower forecasted commodity prices.
During 2014, we recorded impairments of $30 million as a result of abandonment cost revisions relating to the Ozona development in the Gulf of Mexico which ceased production in 2013.
Other impairments of long-lived assets held for use in 2016, 2015,lower forecasted long-term commodity prices and 2014 wereas a result of reduced drilling expectations, reductionsthe anticipated sales of estimated reservescertain non-core international assets. The fair values were measured using the market approach, based upon either anticipated sales proceeds less costs to sell or lower forecasted commodity prices.
a market comparable sales price per boe. This resulted in a Level 2 classification. See Note5 for further information about the divestment of certain non-core properties in our International E&P segment.
In the third quarter of 2015, a partial impairment of $12 million was recorded to an investment in an equity method investee as a result of lower forecasted commodity prices, to a fair value of $604 million. The impairment was reflected in income from equity method investments in our consolidated statement of income.
Oil Sands MiningCanadian discontinued operations
InAs a result of our announced disposition of our Canadian business in the fourthfirst quarter of 2015, impairments2017, we recorded a pre-tax non-cash impairment charge of $26 million were recorded$6.6 billion primarily related to long-livedproperty, plant and equipment. This impairment was recorded for excess net book value over anticipated sales proceeds less costs to sell. Fair values of assets usedheld for sale were determined based upon the anticipated sales proceeds less costs to sell, which resulted in debottlenecking projects. Based on an evaluation by the operator, it was determined that the projects would not continue due to a need to reduce capital intensity and improve efficiency.Level 2 classification. See Note 5 for relevant detail regarding dispositions
Fair values – Financial instruments
Our current assets and liabilities include financial instruments, the most significant of which are receivables, long-term debt and payables. We believe the carrying values of our receivables and payables approximate fair value. Our fair value assessment incorporates a variety of considerations, including (1) the short-term duration of the instruments, (2) our credit rating and (3) our historical incurrence of and expected future insignificance of bad debt expense, which includes an evaluation of counterparty credit risk.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


The following table summarizes financial instruments, excluding receivables, payables and derivative financial instruments, and their reported fair value by individual balance sheet line item at December 31, 20162017 and 2015.2016.
December 31,December 31,
2016 20152017 2016
(In millions)
Fair
Value
 
Carrying
Amount
 
Fair
Value
 
Carrying
Amount
Fair
Value
 
Carrying
Amount
 
Fair
Value
 
Carrying
Amount
Financial assets              
Other current assets(a)$7
 $7
 $
 $
$762
 $761
 $7
 $7
Other noncurrent assets119
 121
 104
 118
159
 161
 105
 108
Total financial assets$126
 $128
 $104
 $118
$921
 $922
 $112
 $115
Financial liabilities              
Other current liabilities$68
 $75
 $34
 $33
$32
 $43
 $68
 $75
Long-term debt, including current portion(a)(b)
7,449
 7,292
 6,723
 7,291
5,976
 5,526
 7,449
 7,292
Deferred credits and other liabilities114
 107
 97
 95
110
 103
 114
 107
Total financial liabilities$7,631
 $7,474
 $6,854
 $7,419
$6,118
 $5,672
 $7,631
 $7,474
(a) 
Includes our two notes receivable relating to the sale of our Canadian business as of December 31, 2017, see note 5 for further information.
(b)
Excludes capital leases, debt issuance costs and historical interest rate swap adjustments.
Fair values of our notes receivable and our financial assets included in other noncurrent assets, and of our financial liabilities included in other current liabilities and deferred credits and other liabilities, are measured using an income approach and most inputs are internally generated, which results in a Level 3 classification. Estimated future cash flows are discounted using a rate deemed appropriate to obtain the fair value.
Most of our long-term debt instruments are publicly-traded. A market approach, based upon quotes from major financial institutions, which are Level 2 inputs, is used to measure the fair value of such debt. The fair value of our debt that is not publicly-traded is measured using an income approach. The future debt service payments are discounted using the rate at which we currently expect to borrow. All inputs to this calculation are Level 3.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


16. Derivatives
For further information regarding the fair value measurement of derivative instruments see Note 15. See Note 1 for discussion of the types of derivatives we use and the reasons for them. All of our interest rate and commodity derivatives are subject to enforceable master netting arrangements or similar agreements under which we may report net amounts. The following tables present the gross fair values of derivative instruments and the reported net amounts along with where they appear on the consolidated balance sheets.
 December 31, 2016  
(In millions)Asset Liability Net Asset Balance Sheet Location
Fair Value Hedges    

  
     Interest rate$3
 $
 $3
 Other current assets
     Interest rate1
 
 1
 Other noncurrent assets
Cash Flow Hedges       
     Interest rate$64
 $
 $64
 Other noncurrent assets
Total Designated Hedges$68
 $
 $68
  
        
Not Designated as Hedges       
     Commodity$
 $60
 $(60) Other current liabilities
Total Not Designated as Hedges$
 $60
 $(60)  
     Total$68
 $60
 $8
  
 December 31, 2015  
(In millions)Asset Liability Net Asset Balance Sheet Location
Fair Value Hedges       
     Interest rate$8
 $
 $8
 Other noncurrent assets
Total Designated Hedges$8
 $
 $8
  
        
Not Designated as Hedges       
     Commodity$51
 $1
 $50
 Other current assets
Total Not Designated as Hedges51
 1
 50
  
     Total$59
 $1
 $58
  

Derivatives Designated as Fair Value Hedges
The following table presents by maturity date, information about our interest rate swap agreements, including the weighted average, London Interbank Offer Rate (“LIBOR”)-based, floating rate.
 December 31, 2016 December 31, 2015
 Aggregate Notional AmountWeighted Average, LIBOR-Based, Aggregate Notional AmountWeighted Average, LIBOR-Based,
Maturity Dates(in millions)Floating Rate (in millions)Floating Rate
October 1, 2017$600
5.10% $600
4.73%
March 15, 2018$300
5.04% $300
4.66%
The pretax effect of derivative instruments designated as hedges of fair value in our consolidated statements of income is summarized in the table below. There is no ineffectiveness related to the fair value hedges.

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


  Gain (Loss)
  Year Ended December 31,
(In millions)Income Statement Location2016 2015 2014
Derivative      
Interest rateNet interest and other$(4) $
 $
Foreign currencyDiscontinued operations
 
 (36)
Hedged Item  
  
  
DebtNet interest and other$4
 $
 $
Accrued taxesDiscontinued operations
 
 36
The table above includes foreign currency forwards in 2014 which hedged the current Norwegian tax liability of the Norway business, which was subsequently reported as discontinued operations. The open positions were transferred to the purchaser of our Norway business upon closing of the sale in the fourth quarter of 2014.
Derivatives Designated as Cash Flow Hedges
During the third quarter of 2016, we entered into forward starting interest rate swaps to hedge the variations in cash flows related to fluctuations in long term interest rates from debt that is probable to be refinanced by us in 2018, specifically interest rate risk associated with future changes in the benchmark treasury rate. The occurrence of the forecasted transaction is probable and each respective derivative contract can be tied to an anticipated underlying dollar notional amount. At conclusion of the hedge in the first quarter of 2018, the final value will be reclassified from accumulated other comprehensive income into earnings. At December 31, 2016, the forward starting interest rate swaps continued to qualify as an effective hedge. The ineffectiveness related to this hedge resulted in a charge of $4 million in 2016. See Note 22 for a summary of amounts reclassified from accumulated other comprehensive loss.
The following table presents, by maturity date, information about our forward starting interest rate swap agreements, including the rate.
  December 31, 2016
  Aggregate Notional Amount Weighted Average, LIBOR
Maturity Dates (in millions) Fixed Rate
March 15, 2018 $750
 1.57%
The following table sets forth the net impact of the derivatives designated as cash flow hedges on other comprehensive income (loss).
  December 31,
(In millions) 2016 2015
Cash Flow Hedges    
  Beginning balance $
 $
  Change in fair value recognized in accumulated other comprehensive loss 64
 
  Reclassification from other comprehensive income (loss) (4) 
  Ending balance $60
 $
At December 31, 2016, accumulated other comprehensive loss included a gain of $39 million, net of tax, related to interest rate cash flow hedges. We do not expect any material reclassification to earnings as an adjustment to net interest and other during the next 12 months.
Derivatives Not Designated as Hedges
We have entered into multiple crude oil and natural gas derivatives indexed to NYMEX WTI and Henry Hub related to a portion of our forecasted North America E&P sales through December 2018. These commodity derivatives consist of three-way collars, swaps, and call options. Three-way collars consist of a sold call (ceiling), a purchased put (floor) and a sold put. The ceiling price is the maximum we will receive for the contract volumes, the floor is the minimum price we will receive, unless the market price falls below the sold put strike price. In this case, we receive the NYMEX WTI/Henry Hub price plus the difference between the floor and the sold put price. These commodity derivatives were not designated as hedges. The following table sets forth outstanding derivative contracts as of December 31, 2016 and the weighted average prices for those contracts:
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Crude Oil (a)
 2017
 First Quarter Second Quarter Third Quarter Fourth Quarter
Three-Way Collars (b)
       
Volume (Bbls/day)50,000 50,000 30,000 30,000
Price per Bbl:       
Ceiling$58.42 $58.42 $59.60 $59.60
Floor$50.30 $50.30 $54.00 $54.00
Sold put$43.50 $43.50 $47.00 $47.00
Sold Call Options (c)
       
Volume (Bbls/day)35,000 35,000 35,000 35,000
Price per Bbl$61.91 $61.91 $61.91 $61.91
(a) Subsequent to December 31, 2016, we entered into 10,000 Bbls/day of fixed-price swaps with a weighted average price of $54.00 indexed to WTI for February - March of 2017.
(b) Subsequent to December 31, 2016, we entered into 20,000 Bbls/day of three-way collars for July - December of 2017 with a ceiling price of $61.52, a floor price of $56.00, and a sold put price of $49.00.
(c) Call options settle monthly.
Natural Gas
 2017 
 First QuarterSecond QuarterThird QuarterFourth Quarter2018
Three-Way Collars (a)
     
Volume (MMBtu/day)60,00090,00090,00090,00020,000
Price per MMBtu     
Ceiling$3.46$3.54$3.54$3.61$3.56
Floor$2.84$3.01$3.01$3.04$3.00
Sold put$2.35$2.48$2.48$2.52$2.50
Swaps     
Volume (MMBtu/day)20,00020,00020,00020,000
Price per MMBtu$2.93$2.93$2.93$2.93$—
(a) Subsequent to December 31, 2016, we entered into three-way collars of 30,000 MMBtus/day for April - September of 2017 with a ceiling price of $3.70, a floor price of $3.35, and a sold put price of $2.75; 30,000 MMBtus/day for October - December of 2017 with a ceiling price of $4.00, a floor price of $3.45, and a sold put price of $2.85; and 70,000 MMBtus/day for January - December of 2018 with a ceiling price of $3.62, a floor price of $3.00, and a sold put price of $2.50.
The mark-to-market impact and settlement of these commodity derivative instruments appears in sales and other operating revenues in our consolidated statements of income for the years ended December 31, 2016 and 2015. There were no commodity derivative instruments during 2014. The 2016 impact was a net loss of $66 million compared to a net gain of $128 million in 2015. Net settlements of commodity derivative instruments for the years ended December 31, 2016 and 2015 was $44 million compared to $78 million, comparatively.
On June 1, 2015, we entered into Treasury rate locks, which expired on the same day, to hedge against timing differences as it related to our Notes offering (see Note 17). Following the execution of the Treasury locks, corresponding interest rates increased during the day of June 1. As a result, the settlement of the Treasury rate locks resulted in a gain of $6 million, which was recognized in net interest and other in our consolidated statements of income.

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


17. Debt
Short-term debt
As of December 31, 2016,2017, we had no borrowings against our $3.4 billion unsecured revolving credit facility (as amended, the "Credit Facility"), as described below.
Revolving Credit Facility
In March 2016,June 2017, we extended the maturity date of our Credit Facility from May 28, 2020 to May 28, 2021. In July 2017, we increased our $3.0$3.3 billion unsecured Credit Facility by $93 million to $3.3 billion and maintained a maturity datetotal of May 2020.$3.4 billion. Fees on the unused commitment of each lender, as well as the borrowing options under the Credit Facility, remain unaffected by this increase.the increase and term extension. We have the ability to request two additional one-year extensions and an option to increase the commitment amount by up to an additional $200$107 million, subject to the consent of any increasing lenders.  The sub-facilities for swing-line loans and letters of credit remain unchanged allowing up to an aggregate amount of $100 million and $500 million, respectively. Fees on the unused commitment of each lender, as well as the borrowing options under the Credit Facility, remain unchanged.
The Credit Facility includes a covenant requiring that our ratio of total debt to total capitalization not exceed 65% as of the last day of each fiscal quarter. If an event of default occurs, the lenders holding more than half of the commitments may terminate the commitments under the Credit Facility and require the immediate repayment of all outstanding borrowings and the cash collateralization of all outstanding letters of credit under the Credit Facility. As of December 31, 2016,2017, we were in compliance with this covenant with a debt-to-capitalization ratio of 29%32%.
Long-term debt
The following table details our long-term debt:
December 31,December 31,
(In millions)2016 20152017 2016
Senior unsecured notes:      
6.000% notes due 2017(a)
682
 682

 682
5.900% notes due 2018(a)
854
 854

 854
7.500% notes due 2019(a)
228
 228

 228
2.700% notes due 2020(a)
600
 600
600
 600
2.800% notes due 2022(a)
1,000
 1,000
1,000
 1,000
9.375% notes due 2022 (b)
32
 32
32
 32
Series A notes due 2022 (b)
3
 3
3
 3
8.500% notes due 2023 (b)
70
 70
70
 70
8.125% notes due 2023 (b)
131
 131
131
 131
3.850% notes due 2025(a)
900
 900
900
 900
4.400% notes due 2027(a)
1,000
 
6.800% notes due 2032(a)
550
 550
550
 550
6.600% notes due 2037(a)
750
 750
750
 750
5.200% notes due 2045(a)
500
 500
500
 500
Capital leases:      
Capital lease obligation of consolidated subsidiary due 2017 – 20499
 9
Capital lease obligation expiring in 2018
 1
Other obligations:      
5.125% obligation relating to revenue bonds due 20371,000
 1,000

 1,000
Total(b)
7,309
 7,309
5,536
 7,301
Unamortized discount(9) (10)(10) (9)
Fair value adjustments(c)
7
 17

 7
Unamortized debt issuance cost(35) (39)(32) (35)
Amounts due within one year(683) (1)
 (683)
Total long-term debt$6,589
 $7,276
$5,494
 $6,581
(a) 
These notes contain a make-whole provision allowing us to repay the debt at a premium to market price.
(b) 
In the event of a change in control, as defined in the related agreements, debt obligations totaling $236 million at December 31, 20162017 may be declared immediately due and payable.
(c) 
See Notes 1513 and 1614 for information on historical interest rate swaps.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Debt Issuance
On June 10, 2015,July 24, 2017, we issued $2$1 billion aggregate principal amount of 4.4% senior unsecured senior notes which consist of the following series:
$600 million of 2.70% senior notes due June 1, 2020
$900 million of 3.85% senior notes due June 1, 2025
$500 million of 5.20% senior notes due June 1, 2045
that will mature on July 15, 2027. Interest on each series ofthe senior unsecured notes is payable semi-annually beginning December 1, 2015.January 15, 2018. We may redeem some or all of the senior unsecured notes at any time at the applicable redemption price, plus accrued interest, if any. The aggregateDuring the third quarter of 2017, we used the net proceeds were usedof $990 million plus existing cash on hand to repayredeem the following senior unsecured notes:
$682 million 6.0% Notes Due in 2017
$854 million 5.9% Notes Due in 2018
$228 million 7.5% Notes Due in 2019

During the year ended 2017, as a result of the above redemption of $1.76 billion in senior unsecured notes, we recognized a loss on early extinguishment of debt of $46 million, primarily due to make-whole call provisions. In connection with the redemption of the senior unsecured notes, we terminated our forward starting interest rate swaps, which resulted in proceeds of $54 million and a gain of approximately $47 million into earnings in 2017. See Note 13 for further detail on our historical forward starting interest rate swaps.
Debt Redemption
In December 2017, we entered into a transaction to purchase $1 billion 0.90% senior notes that maturedof 3.75% municipal revenue bonds due in November 2015,2037, to be issued by the Parish of St. John the Baptist, State of Louisiana (the "Parish"). The Parish will use the proceeds to redeem $1 billion of 5.125% municipal revenue bonds due in 2037 with cash on hand in a refunding transaction. We purchased the $1 billion of 3.75% municipal revenue bonds due in 2037 on their date of issuance to hold for our own account and potential remarketing to the remainder for general corporate purposes.public at a future date.
The following table shows future debt payments:
(In millions)  
2017$683
2018854
$
2019228

2020600
600
2021

20221,035
Thereafter4,944
3,901
Total long-term debt, including current portion$7,309
$5,536

18. Asset Retirement Obligations16. Incentive Based Compensation
Asset retirement obligations primarily consistDescription of estimated costsstock-based compensation plans – The Marathon Oil Corporation 2016 Incentive Compensation Plan (the "2016 Plan") was approved by our stockholders in May 2016 and authorizes the Compensation Committee of the Board of Directors to remove, dismantlegrant stock options, SARs, stock awards (including restricted stock and restore landrestricted stock unit awards) and performance unit awards to employees. The 2016 Plan also allows us to provide equity compensation to our non-employee directors. No more than 55 million shares of our common stock may be issued under the 2016 Plan. For stock options and SARs, the number of shares available for issuance under the 2016 Plan will be reduced by one share for each share of our common stock in respect of which the award is granted. For stock awards (including restricted stock and restricted stock unit awards), the number of shares available for issuance under the 2016 Plan will be reduced by 2.41 shares for each share of our common stock in respect of which the award is granted.
Shares subject to awards under the 2016 Plan that are forfeited, terminated or seabedexpire unexercised become available for future grants. In addition, the number of shares of our common stock reserved for issuance under the 2016 Plan will not be increased by shares tendered to satisfy the purchase price of an award, exchanged for other awards or withheld to satisfy tax withholding obligations. Shares issued as a result of awards granted under the 2016 Plan are generally funded out of common stock held in treasury, except to the extent there are insufficient treasury shares, in which case new common shares are issued.
After approval of the 2016 Plan, no new grants were or will be made from any prior plans. Any awards previously granted under any prior plans shall continue to be exercisable in accordance with their original terms and conditions.
Stock-based awards under the plans
Stock options – We grant stock options under the 2016 Plan. Our stock options represent the right to purchase shares of our common stock at its fair market value on the date of grant. In general, our stock options vest ratably over a three-year period and have a maximum term of ten years from the date they are granted.
SARs - At December 31, 2017, there are no SARs outstanding.
Restricted stock – We grant restricted stock under the 2016 Plan. The restricted stock awards granted to officers generally vest three years from the date of grant, contingent on the recipient’s continued employment. We also grant restricted stock to certain non-officer employees based on their performance within certain guidelines and for retention purposes. The restricted stock awards to non-officers generally vest ratably over a three-year period, contingent on the recipient’s continued employment. Prior to vesting, all restricted stock recipients have the right to vote such stock and receive dividends thereon. The non-vested shares of restricted stock are not transferable and are held by our transfer agent.
Stock-based performance units – We grant stock-based performance units to officers under the 2016 Plan. At the grant date, each unit represents the value of one share of our common stock. These units are settled in cash, and the amount of the payment is based on (1) the vesting percentage, which can be from zero to 200% based on performance achieved and (2) the value of our common stock on the date vesting is determined by the Compensation Committee of the Board of Directors. The performance goals are tied to our total shareholder return (“TSR”) as compared to TSR for a group of peer companies determined by the Compensation Committee of our Board of Directors. Dividend equivalents may accrue during the performance period and would be paid in cash at the end of oil and gas production operations, including bitumen mining operations. Changes in asset retirement obligations were as follows:the performance period based on the number of shares that would represent the value of the units.
 For Year Ended December 31,
(In millions)2016 2015
Beginning balance$1,635
 $1,958
Incurred liabilities, including acquisitions15
 47
Settled liabilities, including dispositions(74) (289)
Accretion expense (included in depreciation, depletion and amortization)85
 105
Revisions of estimates94
 (132)
Held for sale(7) (54)
Ending balance$1,748
 $1,635
2016
Settled liabilitiesRestricted stock units include dispositions, primarily related– We maintain an equity compensation program for our non-employee directors.  All non-employee directors receive annual grants of common stock units.  Any units granted prior to the Gulf2012 must be held until completion of Mexico and Wyoming as well as retirements in the Gulf of Mexico.board
Revisions of estimates were primarily due to changes in timing of abandonment activities as well as changes in cost estimated in the U.K.
Ending balance includes $50 million classified as short-term at December 31, 2016.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


2015service, at which time the non-employee director will receive common shares.  For units granted between 2012 and 2016, common shares will generally vest following completion of board service or three years from the date of grant, whichever is earlier.  For awards issued in 2017 and later, directors may elect to defer settlement of their common stock units until after they cease serving on the Board.  Absent such an election to defer, common shares will vest upon the earlier of three years from the date of grant or completion of board service.  We also grant restricted stock units to certain non-officer international employees which generally vest ratably over a three-year period, contingent on the recipient's continued employment. Grants of restricted stock units to these non-officer international employees are based on their performance and for retention purposes. Common shares will be issued for these restricted stock units after vesting. Prior to vesting, recipients of restricted stock units typically receive dividend equivalent payments, but they may not vote.
Settled liabilitiesTotal stock-based compensation expense include dispositions, primarily– Total employee stock-based compensation expense was $50 million, $51 million and $57 million in 2017, 2016 and 2015, while the Gulftotal related income tax benefits were $19 million and $20 million in 2016 and 2015. Due to the full valuation allowance on our net federal deferred tax assets, we realized no tax benefit during 2017. During 2016 and 2015, cash received upon exercise of Mexicostock option awards was $1 million and the East Texas, North Louisiana$9 million. There was no cash received upon exercise of stock option awards for 2017. There were no tax benefits realized for deductions for stock awards settled during 2017, 2016 and Wilburton, Oklahoma as well as retirements in the Gulf of Mexico and the U.K.2015.
Revisions of estimatesStock option awards were primarily due– During 2017, 2016 and 2015 we granted stock option awards to changes in timingofficer employees. The weighted average grant date fair value of activities inthese awards was based on the U.K. and lower estimated costs across the assets.following weighted average Black-Scholes assumptions:
Held for sale is related to our Neptune field in the Gulf of Mexico.
Ending balance includes $34 million classified as short-term at December 31, 2015.

19. Supplemental Cash Flow Information
 Year Ended December 31,
(In millions)2016 2015 2014
Net cash used in operating activities:     
Interest paid (net of amounts capitalized)$(375) $(325) $(279)
Income taxes paid to taxing authorities (a)
(84) (171) (1,679)
Net cash provided by (used in) financing activities:     
Commercial paper, net:     
Issuances$
 $
 $2,345
Repayments
 
 (2,480)
Commercial paper, net$
 $
 $(135)
Noncash investing activities, related to continuing operations:     
Asset retirement cost increase (decrease)$111
 $(85) $151
Asset retirement obligations assumed by buyer40
 251
 359
Increase in capital expenditure accrual
 
 335

2017 2016 2015
Exercise price per share$15.80 $7.22 $29.06
Expected annual dividend yield1.3% 2.8% 2.9%
Expected life in years6.4
 6.3
 6.2
Expected volatility42% 36% 32%
Risk-free interest rate2.1% 1.4% 1.7%
Weighted average grant date fair value of stock option awards granted$6.07 $1.97 $6.84
(a)
The following is a summary of stock option award activity in 2017.
 Number Weighted Average 
Weighted Average
Remaining
 Aggregate Intrinsic Value
 of Shares Exercise Price Contractual Term (in millions)
Outstanding at beginning of year11,915,533 $27.71    
Granted799,591 $15.80    
Exercised(8,666) $7.22    
Canceled(2,375,682) $33.31    
Outstanding at end of year10,330,776 $25.52 4 years $13
Exercisable at end of year8,661,893
 $27.91 3 years $5
Expected to vest1,650,737
 $13.08 9 years $8
The intrinsic value of stock option awards exercised during 2017 and 2016 were not material. The intrinsic value of stock awards exercised during 2015 was $6 million.
As of December 31, 2017, unrecognized compensation cost related to stock option awards was $4 million, which is expected to be recognized over a weighted average period of one year.
Income taxes paid to taxing authorities includes $1,312 million in 2014 related to discontinued operations.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


20.Restricted stock awards and restricted stock units – The following is a summary of restricted stock and restricted stock unit award activity in 2017.
 Awards 
Weighted Average
Grant Date
Fair Value
Unvested at beginning of year6,933,533
  $14.44
Granted4,198,624
 $16.13
Vested & Exercised(2,472,367) $17.67
Canceled(1,086,945) $15.03
Unvested at end of year7,572,845
  $14.24
The vesting date fair value of restricted stock awards which vested during 2017, 2016 and 2015 was $30 million, $16 million and $26 million. The weighted average grant date fair value of restricted stock awards was $14.24, $14.44 and $30.76 for awards unvested at December 31, 2017, 2016 and 2015.
As of December 31, 2017 there was $67 million of unrecognized compensation cost related to restricted stock awards which is expected to be recognized over a weighted average period of one year.
Stock-based performance unit awards – During 2017, 2016 and 2015 we granted 563,631, 1,205,517 and 382,335 stock-based performance unit awards to officers. At December 31, 2017, there were 1,510,823 units outstanding. Total stock-based performance unit awards expense was $8 million in 2017 and $6 million in 2016. We had no stock-based performance unit awards expense in 2015.
The key assumptions used in the Monte Carlo simulation to determine the fair value of stock-based performance units granted in 2017, 2016 and 2015 were:
 2017 2016 
2015 (a)
Valuation date stock price$16.93 $16.93 $16.93
Expected annual dividend yield1.2% 1.2% 1.2%
Expected volatility54% 34% 33%
Risk-free interest rate1.9% 1.7% 1.4%
Fair value of stock-based performance units outstanding$21.63 $19.86 $0.00
(a) As of December 31, 2017, there were no 2015 performance unit awards outstanding.
17. Defined Benefit Postretirement Plans and Defined Contribution Plan
We have noncontributory defined benefit pension plans covering substantially all domestic employees, as well as U.K. employees who were hired before April 2010. Certain employees located in E.G., who are U.S. or U.K. based, also participate in these plans. Benefits under these plans are based on plan provisions specific to each plan. For the U.K. pension plan, the principal employer and plan trustees reached a decision to close the plan to future benefit accruals effective December 31, 2015.
We also have defined benefit plans for other postretirement benefits covering our U.S. employees. Health care benefits are provided up to age 65 through comprehensive hospital, surgical and major medical benefit provisions subject to various cost-sharing features. Post-age 65 health care benefits are provided to certain U.S. employees on a defined contribution basis. Life insurance benefits are provided to certain retiree beneficiaries. These other postretirement benefits are not funded in advance. Employees hired after 2016 are not eligible for any postretirement health care or life insurance benefits.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Obligations and funded status The following summarizes the obligations and funded status for our defined benefit pension and other postretirement plans.    
Pension Benefits Other BenefitsPension Benefits Other Benefits
2016 2015 2016 20152017 2016 2017 2016
(In millions)U.S. Int’l U.S. Int’l U.S. U.S.U.S. Int’l U.S. Int’l U.S. U.S.
Accumulated benefit obligation386
 583
 518
 579
 227 260378
 599
 386
 583
 221 227
Change in benefit obligations:                      
Beginning balance$525
 $579
 $894
 $651
 $260
 $279
$397
 $583
 $525
 $579
 $227
 $260
Service cost25
 
 29
 14
 2
 3
22
 
 25
 
 2
 2
Interest cost16
 23
 25
 25
 11
 11
13
 17
 16
 23
 8
 11
Plan amendment(a)

 1
 (88) 1
 (38) 

 
 
 1
 
 (38)
Actuarial loss (gain)78
 139
 26
 (29) 11
 (20)42
 (7) 78
 139
 5
 11
Foreign currency exchange rate changes
 (108) 
 (35) 
 

 52
 
 (108) 
 
Divestiture
 
 
 
 
 

 
 
 
 
 
Liability (gain)/loss due to curtailment(b)

 
 (18) (23) 
 2
Settlements paid(240) (36) (335) 
 
 
(84) (31) (240) (36) 
 
Benefits paid(7) (15) (8) (25) (19) (15)(6) (15) (7) (15) (21) (19)
Ending balance$397
 $583
 $525
 $579
 $227
 $260
$384
 $599
 $397
 $583
 $221
 $227
Change in fair value of plan assets:                      
Beginning balance$354
 $608
 $574
 $622
 $
 $
$227
 $595
 $354
 $608
 $
 $
Actual return on plan assets25
 129
 8
 8
 
 
27
 47
 25
 129
 
 
Employer contributions95
 18
 115
 36
 20
 15
52
 17
 95
 18
 21
 20
Foreign currency exchange rate changes
 (109) 
 (33) 
 

 57
 
 (109) 
 
Divestiture
 
 
 
 
 

 
 
 
 
 
Settlements paid(240) (36) (335) 
 
 
(84) (31) (240) (36) 
 
Benefits paid(7) (15) (8) (25) (20) (15)(6) (15) (7) (15) (21) (20)
Ending balance$227
 $595
 $354
 $608
 $
 $
$216
 $670
 $227
 $595
 $
 $
Funded status of plans at December 31$(170) $12
 $(171) $29
 $(227) $(260)$(168) $71
 $(170) $12
 $(221) $(227)
Amounts recognized in the consolidated balance sheets:Amounts recognized in the consolidated balance sheets:           
Noncurrent assets
 12
 
 29
 
 

 71
 
 12
 
 
Current liabilities(4) 
 (8) 
 (21) (20)(6) 
 (4) 
 (21) (21)
Noncurrent liabilities(166) 
 (163) 
 (206) (240)(162) 
 (166) 
 (200) (206)
Accrued benefit cost$(170) $12
 $(171) $29
 $(227) $(260)$(168) $71
 $(170) $12
 $(221) $(227)
Pretax amounts in accumulated other comprehensive loss:Pretax amounts in accumulated other comprehensive loss:           
Net loss (gain)$130
 $81
 $171
 $61
 $25
 $14
$122
 $58
 $130
 $81
 $30
 $25
Prior service cost (credit)(55) 4
 (65) 4
 (63) (28)(45) 3
 (55) 4
 (56) (63)
(a)


The plan amendment in 2015 was a freeze of the final average pay used in the legacy formula of the defined benefit pension plan.
(b)
Related to workforce reductions, which reduced the future expected years of service for employees participating in the plans and the impact of discontinuing accruals for future benefits under the U.K. pension plan effective December 31, 2015.


MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Components of net periodic benefit cost from continuing operations and other comprehensive (income) loss – The following summarizes the net periodic benefit costs and the amounts recognized as other comprehensive (income) loss for our defined benefit pension and other postretirement plans.
Pension Benefits Other BenefitsPension Benefits Other Benefits
Year Ended December 31, Year Ended December 31,Year Ended December 31, Year Ended December 31,
2016 2015 2014 2016 2015 20142017 2016 2015 2017 2016 2015
(In millions)U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S.U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S.
Components of net periodic benefit cost:                                  
Service cost$25
 $
 $29
 $14
 $31
 $16
 $2
 $3
 $3
$22
 $
 $25
 $
 $29
 $14
 $2
 $2
 $3
Interest cost16
 23
 25
 25
 35
 27
 11
 11
 13
13
 17
 16
 23
 25
 25
 8
 11
 11
Expected return on plan assets(18) (35) (30) (37) (34) (32) 
 
 
(13) (30) (18) (35) (30) (37) 
 
 
Amortization:                                  
- prior service cost (credit)(10) 1
 (7) 1
 5
 1
 (3) (4) (6)(10) 
 (10) 1
 (7) 1
 (7) (3) (4)
- actuarial loss14
 
 22
 2
 29
 1
 
 1
 
8
 1
 14
 
 22
 2
 
 
 1
Net curtailment loss (gain)(a)

 
 (5) 4
 
 
 
 (7) 

 
 
 
 (5) 4
 
 
 (7)
Net settlement loss(b)
97
 6
 119
 
 99
 
 
 
 
28
 4
 97
 6
 119
 
 
 
 
Net periodic benefit cost(c)
$124
 $(5) $153
 $9
 $165
 $13
 $10
 $4
 $10
$48
 $(8) $124
 $(5) $153
 $9
 $3
 $10
 $4
Other changes in plan assets and benefit obligations recognized in other comprehensive (income) loss (pretax):                                  
Actuarial loss (gain)(d)
$70
 $41
 $30
 $(25) $149
 $33
 $11
 $(21) $42
$28
 $(26) $70
 $41
 $30
 $(25) $5
 $11
 $(21)
Amortization of actuarial gain (loss)(111) (6) (134) (2) (128) (1) 
 (1) 
(36) (4) (111) (6) (134) (2) 
 
 (1)
Prior service cost (credit)
 1
 (89) 1
 
 
 (38) 
 (42)
 
 
 1
 (89) 1
 
 (38) 
Amortization of prior service credit (cost)10
 (1) 7
 (5) (5) (1) 3
 13
 6
10
 
 10
 (1) 7
 (5) 7
 3
 13
Total recognized in other comprehensive (income) loss$(31) $35
 $(186) $(31) $16
 $31
 $(24) $(9) $6
$2
 $(30) $(31) $35
 $(186) $(31) $12
 $(24) $(9)
Total recognized in net periodic benefit cost and other comprehensive (income) loss$93
 $30
 $(33) $(22) $181
 $44
 $(14) $(5) $16
$50
 $(38) $93
 $30
 $(33) $(22) $15
 $(14) $(5)
(a) 
Related to workforce reductions, which reduced the future expected years of service for employees participating in the plans and the impact of discontinuing accruals for future benefits under the U.K. pension plan effective December 31, 2015.
(b) 
Settlement losses are recorded when lump sum payments from a plan in a period exceed the plan’s total service and interest costs for the period.
(c) 
Net periodic benefit cost reflects a calculated market-related value of plan assets which recognizes changes in fair value over three years.
(d)
Activity in 2014 includes the impact of the sale of our Norway business in the fourth quarter of 2014.
The estimated net loss and prior service credit for our defined benefit pension plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost in 20172018 are $10$13 million and $10 million. The estimated net loss and prior service credit for our other defined benefit postretirement plans that will be amortized from accumulated other comprehensive loss into net periodic benefit cost in 2017 is2018 are $1 million and $7 million.
Plan assumptions – The following summarizes the assumptions used to determine the benefit obligations at December 31, and net periodic benefit cost for the defined benefit pension and other postretirement plans for 2017, 2016 2015 and 2014.2015.
Pension Benefits Other BenefitsPension Benefits Other Benefits
2016 2015 2014 2016 2015 20142017 2016 2015 2017 2016 2015
(In millions)U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S.U.S. Int’l U.S. Int’l U.S. Int’l U.S. U.S. U.S.
Weighted average assumptions used to determine benefit obligation:                                  
Discount rate4.02% 2.70% 4.04% 3.90% 3.71% 3.70% 3.98% 4.36% 4.01%3.55% 2.50% 4.02% 2.70% 4.04% 3.90% 3.54% 3.98% 4.36%
Rate of compensation increase (a)
4.00% 
 4.00% 
 4.00% 3.60% 4.00% 4.00% 4.00%4.00% 
 4.00% 
 4.00% 
 4.00% 4.00% 4.00%
Weighted average assumptions used to determine net periodic benefit cost:                                  
Discount rate3.66% 3.90% 3.79% 3.70% 3.98% 4.60% 4.36% 3.93% 4.69%3.86% 2.70% 3.66% 3.90% 3.79% 3.70% 3.98% 4.36% 3.93%
Expected long-term return on plan assets6.75% 5.50% 6.75% 5.70% 6.75% 5.70% 
 
 
6.50% 4.50% 6.75% 5.50% 6.75% 5.70% 
 
 
Rate of compensation increase (a)
4.00% 
 4.00% 3.60% 5.00% 4.90% 4.00% 4.00% 5.00%4.00% 
 4.00% % 4.00% 3.60% 4.00% 4.00% 4.00%
(a) 
No future benefits will be incurred for the U.K. plan after December 31, 2015. Therefore, rate of compensation increase is no longer applicable to this plan.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Expected long-term return on plan assets – The expected long-term return on plan assets assumption for our U.S. funded plan is determined based on an asset rate-of-return modeling tool developed by a third-party investment group which utilizes underlying assumptions based on actual returns by asset category and inflation and takes into account our U.S. pension plan’s asset allocation. To determine the expected long-term return on plan assets assumption for our international plans, we consider the current level of expected returns on risk-free investments (primarily government bonds), the historical levels of the risk premiums associated with the other applicable asset categories and the expectations for future returns of each asset class. The expected return for each asset category is then weighted based on the actual asset allocation to develop the overall expected long-term return on plan assets assumption.
Assumed weighted average health care cost trend rates
2016 2015 20142017 2016 2015
Initial health care trend rate8.25% 8.00% 6.88%8.00% 8.25% 8.00%
Ultimate trend rate4.50% 4.50% 5.00%4.70% 4.50% 4.50%
Year ultimate trend rate is reached2025
 2024
 2024
2025
 2025
 2024
Employer provided subsidies for post-65 retiree health care coverage were frozen effective January 1, 2017 at January 1, 2016 established amount levels. Company contributions are funded to a Health Reimbursement Account on the retiree’s behalf to subsidize the retiree’s cost of obtaining health care benefits through a private exchange. Therefore, a 1% change in health care cost trend rates would not have a material impact on either the service and interest cost components and the postretirement benefit obligations.
Plan investment policies and strategies – The investment policies for our U.S. and international pension plan assets reflect the funded status of the plans and expectations regarding our future ability to make further contributions. Long-term investment goals are to: (1) manage the assets in accordance with applicable legal requirements; (2) produce investment returns which meet or exceed the rates of return achievable in the capital markets while maintaining the risk parameters set by the plan's investment committees and protecting the assets from any erosion of purchasing power; and (3) position the portfolios with a long-term risk/return orientation. Investment performance and risk is measured and monitored on an ongoing basis through quarterly investment meetings and periodic asset and liability studies.
U.S. plan – The plan’s current targeted asset allocation is comprised of 55% equity securities and 45% other fixed income securities. Over time, as the plan’s funded ratio (as defined by the investment policy) improves, in order to reduce volatility in returns and to better match the plan’s liabilities, the allocation to equity securities will decrease while the amount allocated to fixed income securities will increase. The plan's assets are managed by a third-party investment manager.
International plan – Our international plan's target asset allocation is comprised of 60%55% equity securities and 40%45% fixed income securities. The plan assets are invested in eightten separate portfolios, mainly pooled fund vehicles, managed by several professional investment managers whose performance is measured independently by a third-party asset servicing consulting firm.
Fair value measurements – Plan assets are measured at fair value. The following provides a description of the valuation techniques employed for each major plan asset class at December 31, 20162017 and 2015.2016.
Cash and cash equivalents – Cash and cash equivalents are valued using a market approach and are considered Level 1. This investment also includes a cash reserve account (a collective short-term investment fund) that is valued using an income approach and is considered Level 2.
Equity securities -Investments in common stock and preferred stock and real estate investment trusts ("REIT") are valued using a market approach at the closing price reported in an active market and are therefore considered Level 1. Private equity investments include interests in limited partnerships which are valued based on the sum of the estimated fair values of the investments held by each partnership. These private equity investments are considered Level 3. Investments in mutual funds are valued using a market approach. The shares or units held are traded on the public exchanges and are therefore considered Level 1. Investments in pooled funds are valued using a market approach at the net asset value ("NAV") of units held. The various funds consist of either an equity or fixed income investment portfolio with underlying investments held in U.S. and non-U.S. securities. Nearly all of the underlying investments are publicly-traded. The majority of the pooled funds are benchmarked against a relative public index. These are considered Level 2.
Fixed income securities - Fixed income securities are valued using a market approach. U.S. treasury notes and exchange traded funds ("ETFs") are valued at the closing price reported in an active market and are considered Level 1. Corporate bonds, non-U.S. government bonds, private placements, taxable municipals, GNMA/FNMA pools, and otherYankee bonds are valued using calculated yield curves created by models that incorporate various market factors. Primarily investments are held in U.S. and non-U.S. corporate bonds in diverse industries and are considered Level 2. Other bondsfixed income investments include futures contracts, real estate investment trusts, credit default, zero coupon, and interest rate swaps. The investment in the commingled
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


primarily consist of securities issued by governmental agencies and municipalities. The investment in the commingled fundfunds is valued using the NAV of units held and is considered Level 2.as a practical expedient. The commingled fund consistsfunds consist of an equity and fixed income portfolioportfolios with underlying investments held in U.S. and non-U.S. securities. Pooled funds primarily have investments held in U.S. and non-U.S. publicly traded investment grade government and corporate bonds.bonds and are considered Level 2.
Other – Other investments are comprised ofan international insurance carrier contract and the majority of the underlying investments consist of a mix of non-U.S. publicly traded equity securities valued at the closing price reported in an active market and fixed income securities valued using calculated yield curves.  This asset is considered Level 2. The other investments, an unallocated annuity contract, two limited liability companies, and real estate and U.S. treasury futures. All are considered Level 3, as significant inputs to determine fair value are unobservable.
The following tables present the fair values of our defined benefit pension plan's assets, by level within the fair value hierarchy, as of December 31, 20162017 and 2015.2016.
December 31, 2016December 31, 2017
(In millions)Level 1 Level 2 Level 3 TotalLevel 1 Level 2 Level 3 Total
U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’lU.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l
Cash and cash equivalents$8
 $5
 $
 $
 $
 $
 $8
 $5
$6
 $1
 $
 $
 $
 $
 $6
 $1
Equity securities:                              
Common and preferred stock82
 
 
 
 
 
 82
 
REIT and private equity
 
 
 
 20
 
 20
 
Common stock81
 
 
 
 
 
 81
 
Private equity
 
 
 
 16
 
 16
 
Mutual and pooled funds
 201
 
 159
 
 
 
 360

 151
 
 115
 
 
 
 266
Fixed income securities:                              
U.S. treasury notes and ETFs11
 
 
 
 
 
 11
 
Corporate and other bonds
 
 60
 
 
 
 60
 
Corporate
 
 6
 
 
 
 6
 
Exchange traded funds5
 
 
 
 
 
 5
 
Government19
 
 2
 
 3
 
 24
 
Pooled funds
 
 11
 230
 
 
 11
 230

 
 
 403
 
 
 
 403
REIT and swaps
 
 
 
 
 
 
 
Other
 
 
 
 21
 
 21
 

 
 
 
 19
 
 19
 
Total investments, at fair value101
 206
 71
 389
 41
 
 213
 595
111
 152
 8
 518
 38
 
 157
 670
Commingled funds (a)
            14
 

 
 
 
 
 
 59
 
Total investments$101
 $206
 $71
 $389
 $41
 $
 $227
 $595
$111
 $152
 $8
 $518
 $38
 $
 $216
 $670
December 31, 2015December 31, 2016
(In millions)Level 1 Level 2 Level 3 TotalLevel 1 Level 2 Level 3 Total
U.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’lU.S. Int’l U.S. Int’l U.S. Int’l U.S. Int’l
Cash and cash equivalents$47
 $6
 $1
 $
 $
 $
 $48
 $6
$8
 $5
 $
 $
 $
 $
 $8
 $5
Equity securities:                              
Common and preferred stock115
 
 
 
 
 
 115
 
REIT and private equity1
 
 
 
 23
 
 24
 
Common stock82
 
 
 
 
 
 82
 
Private equity
 
 
 
 20
 
 20
 
Mutual and pooled funds
 218
 
 152
 
 
 
 370

 201
 
 159
 
 
 
 360
Fixed income securities:                              
U.S. treasury notes and ETFs12
 
 
 
 
 
 12
 
Corporate and other bonds
 
 105
 
 
 
 105
 
Corporate
 
 52
 
 
 
 52
 
Exchange traded funds5
 
 
 
 
 
 5
 
Government6
 
 19
 
 
 
 25
 
Pooled funds
 
 
 232
 
 
 
 232

 
 
 230
 
 
 
 230
REIT and Swaps
 
 2
 
 
 
 2
 
Other
 
 
 
 25
 
 25
 

 
 
 
 21
 
 21
 
Total investments, at fair value175
 224
 108
 384
 48
 
 331
 608
101
 206
 71
 389
 41
 
 213
 595
Commingled funds (a)
            23
 

 
 
 
 
 
 14
 
Total investments$175
 $224
 $108
 $384
 $48
 $
 $354
 $608
$101
 $206
 $71
 $389
 $41
 $
 $227
 $595
(a)
After the adoption of the FASB update for the fair value hierarchy, we separately report the investments for which fair value was measured using the net asset value per share as a practical expedient. Amounts presented in this table are intended to reconcile the fair value hierarchy to the pension plan assets. See Note 2 for further information on the FASB update.

The activity during the year ended December 31, 20162017 and 2015,2016, for the assets using Level 3 fair value measurements was immaterial.



MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Cash flows
Estimated future benefit payments – The following gross benefit payments, which were estimated based on actuarial assumptions applied at December 31, 20162017 and reflect expected future services, as appropriate, are to be paid in the years indicated.
Pension Benefits Other BenefitsPension Benefits Other Benefits
(In millions)U.S. Int’l U.S.U.S. Int’l U.S.
2017$34
 $17
 $21
201835
 17
 21
$43
 $17
 $21
201934
 18
 20
40
 18
 20
202035
 18
 19
37
 17
 20
202134
 20
 19
33
 19
 19
2022 through 2025163
 116
 78
202230
 21
 18
2023 through 2027123
 118
 74
Contributions to defined benefit plans – We expect to make contributions to the funded pension plans of up to $60$65 million in 2017.2018. Cash contributions to be paid from our general assets for the unfunded pension and postretirement plans are expected to be approximately $5$6 million and $21 million in 2017.2018.
Contributions to defined contribution plans – We contribute to several defined contribution plans for eligible employees. Contributions to these plans totaled $20 million, $20 million and $25$20 million in 2017, 2016 2015 and 2014.2015.

21. Incentive Based Compensation
Description of stock-based compensation plans – The Marathon Oil Corporation 2016 Incentive Compensation Plan (the "2016 Plan") was approved by our stockholders in May 2016 and authorizes the Compensation Committee of the Board of Directors to grant stock options, SARs, stock awards (including restricted stock and restricted stock unit awards) and performance unit awards to employees. The 2016 Plan also allows us to provide equity compensation to our non-employee directors. No more than 55 million shares of our common stock may be issued under the 2016 Plan. For stock options and SARs, the number of shares available for issuance under the 2016 Plan will be reduced by one share for each share of our common stock in respect of which the award is granted. For stock awards (including restricted stock and restricted stock unit awards), the number of shares available for issuance under the 2016 Plan will be reduced by 2.41 shares for each share of our common stock in respect of which the award is granted.
Shares subject to awards under the 2016 Plan that are forfeited, are terminated or expire unexercised become available for future grants. In addition, the number of shares of our common stock reserved for issuance under the 2016 Plan will not be increased by shares tendered to satisfy the purchase price of an award, exchanged for other awards or withheld to satisfy tax withholding obligations. Shares issued as a result of awards granted under the 2016 Plan are generally funded out of common stock held in treasury, except to the extent there are insufficient treasury shares, in which case new common shares are issued.
After approval of the 2016 Plan, no new grants were or will be made from any prior plans. Any awards previously granted under any prior plans shall continue to be exercisable in accordance with their original terms and conditions.
Stock-based awards under the plans
Stock options – We grant stock options under the 2016 Plan. Our stock options represent the right to purchase shares of our common stock at its fair market value on the date of grant. In general, our stock options vest ratably over a three-year period and have a maximum term of ten years from the date they are granted.
SARs - At December 31, 2016, there are no SARs outstanding.
Restricted stock – We grant restricted stock under the 2016 Plan. The restricted stock awards granted to officers generally vest three years from the date of grant, contingent on the recipient’s continued employment. We also grant restricted stock to certain non-officer employees based on their performance within certain guidelines and for retention purposes. The restricted stock awards to non-officers generally vest ratably over a three-year period, contingent on the recipient’s continued employment. Prior to vesting, all restricted stock recipients have the right to vote such stock and receive dividends thereon. The non-vested shares of restricted stock are not transferable and are held by our transfer agent.
Stock-based performance units – We grant stock-based performance units to officers under the 2016 Plan. At the grant date, each unit represents the value of one share of our common stock. These units are settled in cash, and the amount of the payment is based on (1) the vesting percentage, which can be from zero to 200% based on performance achieved and (2) the
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


value of our common stock on the date vesting is determined by the Compensation Committee of the Board of Directors. The performance goals are tied to our total shareholder return (“TSR”) as compared to TSR for a group of peer companies determined by the Compensation Committee of our Board of Directors. Dividend equivalents may accrue during the performance period and would be paid in cash at the end of the performance period based on the number of shares that would represent the value of the units.
Restricted stock units – We maintain an equity compensation program for our non-employee directors under the 2016 Plan.  All non-employee directors receive annual grants of common stock units. Common shares will generally be issued for units granted on or after January 1, 2012 following completion of board service or three years from the date of grant, whichever is earlier. Directors may elect to defer units granted in 2017 or subsequent years until after completion of board service. Any units granted prior to 2012 must be held until completion of board service, at which time the non-employee director will receive common shares. We also grant restricted stock units to certain non-officer international employees which generally vest ratably over a three-year period, contingent on the recipient's continued employment. Grants of restricted stock units to these non-officer international employees are based on their performance and for retention purposes. Common shares will be issued for these restricted stock units after vesting. Prior to vesting, recipients of restricted stock units typically receive dividend equivalent payments, but they may not vote.
Total stock-based compensation expense – Total employee stock-based compensation expense was $51 million, $57 million and $70 million in 2016, 2015 and 2014, while the total related income tax benefits were $19 million, $20 million and $25 million in the same years. In 2016, 2015 and 2014, cash received upon exercise of stock option awards was $1 million, $9 million and $136 million. Tax benefits realized for deductions for stock awards settled during 2014 totaled $51 million. There were no tax benefits realized for deductions for stock awards settled during 2015 and 2016.
Stock option awards – During 2016 and 2015, we granted stock option awards to officer employees. During 2014, we granted stock option awards to both officer and non-officer employees. The weighted average grant date fair value of these awards was based on the following weighted average Black-Scholes assumptions:

2016 2015 2014
Exercise price per share$7.22 $29.06 $34.49
Expected annual dividend yield2.8% 2.9% 2.3%
Expected life in years6.3
 6.2
 5.9
Expected volatility36% 32% 38%
Risk-free interest rate1.4% 1.7% 1.8%
Weighted average grant date fair value of stock option awards granted$1.97 $6.84 $10.50
The following is a summary of stock option award activity in 2016.
 Number Weighted Average 
Weighted Average
Remaining
 Average Intrinsic Value
 of Shares Exercise Price Contractual Term (in millions)
Outstanding at beginning of year12,665,419 $29.97    
Granted1,680,000 $7.22    
Exercised(46,191) $17.44    
Canceled(2,383,695) $25.47    
Outstanding at end of year11,915,533 $27.71 4 years $
Exercisable at end of year9,856,556
 $30.15 3 years $
Expected to vest2,051,140
 $16.05 9 years $
The intrinsic value of stock option awards exercised during 2015 and 2014 were $6 million and $83 million. The intrinsic value in 2016 is not material.
As of December 31, 2016, unrecognized compensation cost related to stock option awards was $3 million, which is expected to be recognized over a weighted average period of one year.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Restricted stock awards and restricted stock units – The following is a summary of restricted stock and restricted stock unit award activity in 2016.
 Awards 
Weighted Average
Grant Date
Fair Value
Unvested at beginning of year4,017,344
  $30.76
Granted5,725,655
 $8.57
Vested & Exercised(1,498,431) $31.67
Canceled(1,311,035) $19.13
Unvested at end of year6,933,533
  $14.44
The vesting date fair value of restricted stock awards which vested during 2016, 2015 and 2014 was $16 million, $26 million and $70 million. The weighted average grant date fair value of restricted stock awards was $14.44, $30.76 and $34.04 for awards unvested at December 31, 2016, 2015 and 2014.
As of December 31, 2016 there was $63 million of unrecognized compensation cost related to restricted stock awards which is expected to be recognized over a weighted average period of one year.
Stock-based performance unit awards – During 2016, 2015 and 2014 we granted 1,205,517, 382,335 and 221,491 stock-based performance unit awards to officers. At December 31, 2016, there were 1,249,719 units outstanding. Total stock-based performance unit awards expense was $6 million in both 2016 and 2014. We had no stock-based performance unit awards expense in 2015.
The key assumptions used in the Monte Carlo simulation to determine the fair value of stock-based performance units granted in 2016, 2015 and 2014 were:
 2016 2015 
2014 (a)
Valuation date stock price$17.31 $17.31 n/a
Expected annual dividend yield1.1% 1.1% n/a
Expected volatility58% 68% n/a
Risk-free interest rate1.3% 0.9% n/a
Fair value of stock-based performance units outstanding$19.37 $11.17 n/a
(a)As of December 31, 2016, there were no 2014 performance unit awards outstanding.

22.18.  Reclassifications Out of Accumulated Other Comprehensive Loss
The following table presents a summary of amounts reclassified from accumulated other comprehensive loss:
Year Ended December 31, Year Ended December 31, 
(In millions)20162015 Income Statement Line2017 2016 Income Statement Line
Postretirement and postemployment plansPostretirement and postemployment plans      
Amortization of actuarial loss$(14)$(24) General and administrative$(9) $(14) General and administrative
Net settlement loss(103)(119) General and administrative(32) (103) General and administrative
Net curtailment gain
8
 General and administrative
Derivative hedges      
Recognized gain on terminated derivative hedge46
 
 Net interest and other
Ineffective portion of derivative hedge4

 Net interest and other1
 4
 Net interest and other
(113)(135) Income (loss) from operations6
 (113) Income (loss) from operations
41
51
 Benefit for income taxes(40) 41
 (Provision) benefit for income taxes
Total reclassifications to expense, net of tax$(34) $(72) Income (loss) from continuing operations
Foreign currency hedges    
Net recognized loss in discontinued operations, net of tax(30) 
 Income (loss) from discontinued operations
Total reclassifications to expense$(72)$(84) Net income (loss)$(64) $(72) 
23.19. Supplemental Cash Flow Information
 Year Ended December 31,
(In millions)2017 2016 2015
Net cash used in operating activities:     
Interest paid (net of amounts capitalized)$(379) $(375) $(325)
Income taxes paid to taxing authorities  (a)
(391) (84) (171)
Noncash investing activities, related to continuing operations:     
Changes in asset retirement costs$(202) $110
 $(95)
Asset retirement obligations assumed by buyer14
 40
 251
Increase in capital expenditure accrual176
 
 
Notes receivable for disposition of assets748
 
 
(a) Includes a payment of $108 million made to U.K. taxing authorities to preserve our appeal rights, see Note 7 - Income Taxes for additional discussion.
20. Other Items
Net interest and other
 Year Ended December 31,
(In millions)2017 2016 2015
Interest:     
Interest income$34
 $14
 $9
Interest expense(380) (398) (350)
Income on interest rate swaps53
 13
 11
Interest capitalized3
 18
 19
Total interest(290) (353) (311)
Other:     
Net foreign currency gain (loss)8
 6
 4
Other12
 15
 21
Total other20
 21
 25
Net interest and other$(270) $(332) $(286)

Foreign currency – Aggregate foreign currency gains (losses) were included in the consolidated statements of income as follows:
 Year Ended December 31,
(In millions)2017 2016 2015
Net interest and other$8
 $6
 $4
Provision for income taxes57
 (32) (11)
Aggregate foreign currency gains (losses)$65
 $(26) $(7)

MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


21. Equity Method Investments and Related Party Transactions
During 2017, 2016 and 2015 only our equity method investees were considered related parties and they included:
EGHoldings, in which we have a 60% noncontrolling interest. EGHoldings is engaged in LNG production activity.
Alba Plant LLC, in which we have a 52% noncontrolling interest. Alba Plant LLC processes LPG.
AMPCO, in which we have a 45% interest. AMPCO is engaged in methanol production activity.
Our equity method investments are summarized in the following table:
 Ownership as of December 31,
(In millions)December 31, 2017 2017 2016
EGHoldings60% $456
 $550
Alba Plant LLC52% 214
 215
AMPCO45% 177
 165
Other investments  
 1
Total  $847
 $931
Dividends and partnership distributions received from equity method investees (excluding distributions that represented a return of capital previously contributed) were $276 million in 2017, $192 million in 2016 and $178 million in 2015.
Summarized financial information for equity method investees is as follows:
(In millions)2017 2016 2015
Income data – year (a):
     
Revenues and other income$1,294
 $770
 $769
Income from operations631
 346
 313
Net income508
 313
 280
Balance sheet data – December 31:     
Current assets$586
 $525
  
Noncurrent assets1,044
 1,173
  
Current liabilities221
 218
  
Noncurrent liabilities94
 47
  
(a)
See Item 15 Exhibits, Financial Statement Schedules which contains the Alba Plant LLC audited financial statements, which have been included pursuant to Rule 3-09 of Regulation S-X.
Revenues from related parties were $60 million, $54 million and $51 million in 2017, 2016 and 2015, with the majority related to EGHoldings in all years. Purchases from related parties were $132 million, $103 million and $207 million in 2017, 2016 and 2015 with the majority related to Alba Plant LLC in all years.
Current receivables from related parties at December 31, 2017 and 2016, were $24 million, and $23 million. Payables to related parties were $14 million and $11 million at December 31, 2017 and 2016, with the majority related to Alba Plant LLC.
22. Stockholders’ Equity
In March 2016, we issued 166,750,000 shares of our common stock, par value $1 per share, at a price of $7.65 per share, excluding underwriting discounts and commissions, for net proceeds of $1,236 million. The proceeds were used to strengthen our balance sheet and for general corporate purposes, including funding a portion of our Capital Development Program.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


There were no share repurchases during 20162017 or 2015. In 2014 we acquired 29 million common shares at a cost of $1 billion2016 under our share repurchase program, initially authorized in 2006, bringing our total repurchases to 121 million common shares at a cost of $4.7 billion.publicly announced plans or programs. As of December 31, 20162017 the total remaining share repurchase authorization was $1.5 billion. Purchases under the program may be in either open market transactions, including block purchases, or in privately negotiated transactions using cash on hand, cash generated from operations, proceeds from potential asset sales or cash from available borrowings to acquire shares. This program may be changed based upon our financial condition or changes in market conditions and is subject to termination prior to completion. The repurchase program does not include specific price targets or timetables.
MARATHON OIL CORPORATION
24.Notes to Consolidated Financial Statements


23. Leases
We lease a wide variety of facilities and equipment under operating leases, including land, building space, equipment and vehicles. Most long-term leases include renewal options and, in certain leases, purchase options. Future minimum commitments for capital lease obligations and for operating lease obligations having noncancellable lease terms in excess of one year are as follows:
(In millions)Capital Lease Obligations Operating Lease ObligationsOperating Lease Obligations
2017$2
 $28
20181
 28
$29
20191
 27
28
20201
 27
27
20211
 26
26
20225
Later years15
 19
4
Sublease rentals
 

Total minimum lease payments$21
 $155
$119
Less imputed interest costs(12)  
Present value of net minimum lease payments$9
  
* Future minimum commitments for capital lease obligations are nil as of December 31, 2017.
Operating lease rental expense related to continuing operations was $93$87 million, $104$87 million and $120$99 million in 2017, 2016 2015 and 2014.2015. 

25.24. Commitments and Contingencies
The U.K. tax authorities have challenged the timing of deductibility for certain Brae area decommissioning costs, which we claimed for U.K. corporation tax purposes.  The dispute relates to the timing of the deduction and does not dispute the general deductibility of decommissioning costs. In the third quarter of 2017, a hearing took place at the U.K.’s First-tier Tribunal with respect to this tax deduction.  In the fourth quarter of 2017, we received notification from the U.K.’s First-tier Tribunal that the judge sided with the U.K. tax authorities with respect to the timing of the decommissioning cost deductions.  We intend to appeal this decision and estimate that any revisions to current and deferred tax liabilities, if we do not prevail in the appeals process, would have no cumulative adverse earnings impact on our consolidated results of operations.  In accordance with U.K. regulations, we have paid the amount of tax and interest in question, approximately $108 million, prior to our appeal.  As a result of the negative ruling we no longer consider this position to be more-likely-than-not to be sustained and have created an uncertain tax position related to the Brae area decommissioning costs.  The payment of the tax and interest to the U.K. tax authorities is not to settle the position, but a regulatory requirement to appeal in the U.K.  If we ultimately prevail in appeals, the U.K. tax authorities will refund the tax and interest, however, if we ultimately lose in appeals no material future payments related to this issue will be required.  See Note 7 for further detail.
We are continuously undergoing examination of our U.S. federal income tax returns by the IRS.  These audits have been completed through the 2014 tax year, except for tax years 2010 and 2011. During the third quarter of 2017, we received a partnership adjustment notification related to the 2010 and 2011 tax years, for which we have filed a Tax Court Petition in the fourth quarter of 2017.  We believe that it is more likely than not that we will prevail.
We are a defendant in a number of legal and administrative proceedings arising in the ordinary course of business including, but not limited to, royalty claims, contract claims, tax disputes and environmental claims. While the ultimate outcome and impact to us cannot be predicted with certainty, we believe the resolution of these proceedings will not have a material adverse effect on our consolidated financial position, results of operations or cash flows. Certain of these matters are discussed below.
Environmental matters – We are subjecthave incurred and will continue to incur capital, operating and maintenance, and remediation expenditures as a result of federal, state, local and foreign laws and regulations relating to the environment. If these expenditures, as with all costs, are not ultimately reflected in the prices of our products and services, our operating results will be adversely affected.  We believe that substantially all of our competitors must comply with similar environmental laws and regulations.  However, the specific impact on each competitor may vary depending on a number of factors, including the age and location of its operating facilities, marketing areas and production processes. These laws generally provide for control of pollutants released into the environment and require responsible parties to undertake remediation of hazardous waste disposal sites. Penalties may be imposed for noncompliance.
At December 31, 20162017 and 2015,2016, accrued liabilities for remediation were not significant.material. It is not presently possible to estimate the ultimate amount of all remediation costs that might be incurred or the penalties that may be imposed.
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


Guarantees We have entered into a performance guarantee related to asset retirement obligations with aggregate maximum potential undiscounted payments totaling $30$35 million as of December 31, 2016.2017. Under the terms of this guarantee arrangement, we would be required to perform should the guaranteed party fail to fulfill its obligations under the specified arrangements.
Over the years, we have sold various assets in the normal course of our business. Certain of the related agreements contain performance and general guarantees, including guarantees regarding inaccuracies in representations, warranties, covenants and agreements, and environmental and general indemnifications that require us to perform upon the occurrence of a triggering event or condition. These guarantees and indemnifications are part of the normal course of selling assets. We are typically not able to calculate the maximum potential amount of future payments that could be made under such contractual provisions because of the variability inherent in the guarantees and indemnities. Most often, the nature of the guarantees and indemnities
MARATHON OIL CORPORATION
Notes to Consolidated Financial Statements


is such that there is no appropriate method for quantifying the exposure because the underlying triggering event has little or no past experience upon which a reasonable prediction of the outcome can be based.
Contract commitments – At December 31, 20162017 and 2015,2016, contractual commitments to acquire property, plant and equipment totaled $144$102 million and $371$144 million.
In connection with the sale of our operated producing properties in the greater Ewing Bank area and non-operated producing interests in the Petronius and Neptune fields in the Gulf of Mexico, we retained an overriding royalty interest in the properties. As part of the sale agreement, proceeds associated with the production of our override, up to $70 million, are dedicated solely to the satisfaction of the corresponding future abandonment obligations of the properties. The term of our override ends once sales proceeds equal $70 million.



Select Quarterly Financial Data (Unaudited)




 2016 2015
(In millions, except per share data)1st Qtr. 2nd Qtr. 3rd Qtr. 4th Qtr. 1st Qtr. 2nd Qtr. 3rd Qtr. 4th Qtr.
Revenues$772
 $959
 $1,100
 $1,200
 $1,484
 $1,490
 $1,384
 $1,164
Income (loss) before income taxes (a)
(683) (238) (290) (24) (420) (392) (1,145) (1,001)
Net income (loss) (b)
$(407) $(170) $(192) $(1,371) $(276) $(386) $(749) $(793)
                
Basic net income (loss) per share($0.56) ($0.20) ($0.23) ($1.62) ($0.41) ($0.57) ($1.11) ($1.17)
Diluted net income (loss) per share($0.56) ($0.20) ($0.23) ($1.62) ($0.41) ($0.57) ($1.11) ($1.17)
Dividends paid per share$0.05 $0.05 $0.05 $0.05 $0.21 $0.21 $0.21 $0.05
 2017 2016
(In millions, except per share data)1st Qtr. 2nd Qtr. 3rd Qtr. 4th Qtr. 1st Qtr. 2nd Qtr. 3rd Qtr. 4th Qtr.
Revenues$988
 $993
 $1,162
 $1,230
 $612
 $761
 $861
 $936
Income (loss) from continuing operations before income taxes (a)
(16) (112) (458) 132
 (613) (192) (313) (46)
Income (loss) from continuing operations(50) (153) (599) (28) (360) (138) (206) (1,383)
Discontinued operations (b)
(4,907) 14
 
 
 (47) (32) 14
 12
Net income (loss) (c)
$(4,957) $(139) $(599) $(28) $(407) $(170) $(192) $(1,371)
                
Income (loss) per share:               
Continuing operations$(0.06) $(0.18) $(0.70) $(0.03) $(0.49) $(0.16) $(0.24) $(1.63)
Discontinued operations (b)
$(5.78) $0.02
 $
 $
 $(0.07) $(0.04) $0.01
 $0.01
Basic net income (loss)$(5.84) $(0.16) $(0.70) $(0.03) $(0.56) $(0.20) $(0.23) $(1.62)
Dividends paid per share$0.05
 $0.05
 $0.05
 $0.05
 $0.05
 $0.05
 $0.05
 $0.05
(a)
Includes impairments to producingproved properties of $24 million and $201 million in the fourth and third quarter of 2017 and $47 million in the third quarter of 2016, $28 million in the 4th quarter2016. Also includes unproved property impairments and exploratory dry well costs of 2015, $333$215 million in the third quarter of 2015,2017 and $44 million in the second quarter of 2015. Also includes unproved property impairments of $118 million in the second quarter of 2016, $302 million in the fourth quarter of 2015, and $553 million in the third quarter of 2015 (see2016. (See Item 8. Financial Statements and Supplementary Data – Note 13 to the consolidated financial statements). Includes a goodwill impairment of $340 million in 2015 related to the N.A. E&P reporting unit. (see Item 8. Financial Statements and Supplementary Data – Note 14 to the consolidated financial statements).
(b)
We closed on the sale of our Canadian business in the second quarter of 2017. The Canadian business is reflected as discontinued operations in all periods presented. Included in the first quarter of 2017 is an after-tax non-cash impairment charge of $4.96 billion, primarily related to the property, plant, and equipment.
(c)
Includes the increase of a valuation allowance on certain of our deferred tax assets for $1,346 million in the fourth quarter of 2016 (see Item 8. Financial Statements and Supplementary Data – Note 9 to the consolidated financial statements).


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


The supplementary information is disclosed by the following geographic areas: the U.S.; Canada; E.G.; Libya; Other Africa, which primarily includes activities in Gabon, Kenya, Ethiopia and Libya;Gabon; and Other International ("Other Int’l"), which includes the U.K. and the Kurdistan Region of Iraq. We closed the sale of our Angola assets and our NorwayCanada business in 2014,2017 and both are shownhave reflected this business as discontinued operations ("Disc Ops") in all periods presented. See Note 5 for further details on our Canadian disposition.
Preparation of Reserve Estimates
All estimates of reserves are made in compliance with SEC Rule 4-10 of Regulation S-X. Crude oil and condensate, NGL, natural gas and our historical synthetic crude oil reserve estimates are reviewed and approved by our Corporate Reserves Group ("CRG"), which includes our Director of Corporate Reserves and his staff of Reserve Coordinators. Crude oil and condensate, NGLs and natural gas reserve estimates are developed or reviewed by Qualified Reserves Estimators ("QREs"). QREs are petro-technical professionals located throughout our organization who meet the qualifications we have established for employees engaged in estimating reserves and resources. QREs have the education, experience, and training necessary to estimate reserves and resources in a manner consistent with all external reserve estimation regulations and internal resource estimation directives and practices. QREs generally hold at least a Bachelor of Science degree in the appropriate technical field, have a minimum of three years of industry experience with at least one year in reserve estimation and have completed our QRE training course. All reserves changes (including proved) must be approved by the CRG. Additionally, any change to proved reserve estimates in excess of 5 mmboe on a total field basis, within a single month, must be approved by the Director of Corporate Reserves.
The Director of Corporate Reserves, who reports to our Chief Financial Officer, has a Bachelor of Science degree in petroleum engineering and is a registered Professional Engineer in the State of New Mexico. In his 31 years with Marathon Oil, he has held numerous engineering and management positions, including more recently managing reservoir engineering and geoscience for our Eagle Ford development in South Texas. He is a 25 year member of the Society of Petroleum Engineers ("SPE").
Technologies used in proved reserves estimation includes statistical analysis of production performance, decline curve analysis, pressure and rate transient analysis, pressure gradient analysis, reservoir simulation and volumetric analysis. The observed statistical nature of production performance coupled with highly certain reservoir continuity or quality within the reliable technology areas and sufficient proved developed locations establish the reasonable certainty criteria required for booking proved reserves.
Historical estimates of synthetic crude oil reserves were prepared by GLJ Petroleum Consultants of Calgary, Alberta, Canada, third-party consultants for 2015. Their report was filed as an exhibit to the prior periods.year Annual Report on Form 10-K. The individual responsible for the estimates of our synthetic crude oil reserves had 15 years of experience in petroleum engineering, has conducted surface mineable oil sands evaluations since 2009 and is a registered Practicing Professional Engineer in the Province of Alberta.
Audits of Estimates
We engage third-party consultants to provide, at a minimum, independent estimates for fields that comprise 80% of our total proved reserves over a rolling four-year period. We exceeded this percentage for the four-year period ended December 31, 2017, with 84% of our total proved reserves independently audited. An audit tolerance at a field level of +/- 10% to our internal estimates has been established. Should the third-party consultants’ initial analysis fall outside our tolerance band, both parties will re-examine the information provided, request additional data and refine their analysis, if appropriate. In the very limited instances where differences outside the 10% tolerance cannot be resolved by year end, a plan to resolve the difference is developed and executive management consent is obtained. The audit process did not result in any significant changes to our reserve estimates for 2017, 2016 or 2015.
During 2017, 2016 and 2015, Netherland, Sewell & Associates, Inc. prepared a reserves certification for the Alba field in E.G. The NSAI summary reports are filed as an exhibit to this Annual Report on Form 10-K. Members of the NSAI team have multiple years of industry experience, having worked for large, international oil and gas companies before joining NSAI. NSAI’s technical team members meet or exceed the education, training, and experience requirements set forth in the Standards Pertaining to the Estimating and Auditing of Oil and Gas Reserves Information promulgated by the Society of Petroleum Engineers. The senior technical advisor has over 13 years of practical experience in petroleum engineering and the estimation and evaluation of reserves and is a registered Professional Engineer in the State of Texas. The second team member has over 11 years of practical experience in petroleum geosciences and is a licensed Professional Geoscientist in the State of Texas.
Ryder Scott Company also performed audits of the prior years' reserves for several of our fields in 2017, 2016 and 2015. Their summary reports are filed as exhibits to this Annual Report on Form 10-K. The team lead for Ryder Scott has over 35 years of industry experience, having worked for a major financial advisory services group before joining Ryder Scott. He is a 26 year member of SPE and is a registered Professional Engineer in the State of Texas.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves
The estimation of net recoverable quantities of crude oil and condensate, natural gas liquids, natural gas and our historical synthetic crude oil is a highly technical process which is based upon several underlying assumptions that are subject to change. Proved reserves are determined using "SEC Pricing", calculated as an unweighted arithmetic average of the first-day-of-the-month closing price for each month. If commodity pricing were to significantly drop-below average prices used to estimate 2016 proved reserves (see table below), we would expect price related reserve revisions that could have a material impact on proved reserve volumes and the present value of our proved reserves. In this scenario, our OSM proved reserves represent the largest risk to be reclassified to non-proved reserve or resource category. See Item 1A. Risk Factors and Item 7. Management’s Discussion and Analysis of Financial Condition, Cash Flows and Liquidity – Critical Accounting Estimates – Estimated Quantities of Net Reserves for the table providing our 20162017 SEC pricing of benchmark prices and the underlying assumptions used. For a discussion of our reserve estimation process, including the use of third-party audits, see Item 1. Business – Reserves.
The table below provides the 20162017 SEC pricing for certain benchmark prices:
SEC Pricing 2016SEC Pricing 2017
WTI Crude oil (per bbl)
$42.75
$51.34
Henry Hub natural gas (per mmbtu)
$2.49
$2.98
Brent crude oil (per bbl)
$43.53
$54.39
Mont Belvieu NGLs (per bbl)
$15.89
$22.03











































Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves
(mmbbl)U.S. Canada 
E.G.(a)
 
Other
Africa
 Other Int'l Cont Ops Disc Ops TotalU.S. 
E.G.(a)
 Libya Other Int'l Cont Ops Disc Ops Total
Crude oil and condensate                            
Proved developed and undeveloped reserves:
Beginning of year - 2014497
 
 64
 215
 25
 801
 91
 892
Revisions of previous estimates36
 
 (1) (4) 1
 32
 10
 42
Improved recovery2
 
 
 
 
 2
 
 2
Purchases of reserves in place6
 
 
 
 
 6
 
 6
Extensions, discoveries and        

 

    
other additions153
 
 1
 
 7
 161
 3
 164
Production(57) 
 (7) (3) (4) (71) (17) (88)
Sales of reserves in place(3) 
 
 
 
 (3) (87) (90)
End of year - 2014634
 
 57
 208
 29
 928
 
 928
Beginning of year - 2015634
 57
 208
 29
 928
 
 928
Revisions of previous estimates(109) 
 2
 (7) (2) (116) 
 (116)(57) 2
 (7) (2) (64) 
 (64)
Improved recovery1
 
 
 
 
 1
 
 1
1
 
 
 
 1
 
 1
Purchases of reserves in place
 
 
 
 
 
 
 

 
 
 
 
 
 
Extensions, discoveries and        

 

   

             
other additions122
 
 
 
 
 122
 
 122
70
 
 
 
 70
 
 70
Production(62) 
 (7) 
 (5) (74) 
 (74)(62) (7) 
 (5) (74) 
 (74)
Sales of reserves in place(6) 
 
 
 
 (6) 
 (6)(6) 
 
 
 (6) 
 (6)
End of year - 2015580
 
 52
 201
 22
 855
 
 855
580
 52
 201
 22
 855
 
 855
Revisions of previous estimates(97) 
 1
 (28) 3
 (121) 
 (121)55
 1
 (28) 3
 31
 
 31
Improved recovery4
 
 
 
 
 4
 
 4
4
 
 
 
 4
 
 4
Purchases of reserves in place12
 
 
 
 
 12
 
 12
12
 
 
 
 12
 
 12
Extensions, discoveries and        

 

   

             
other additions189
 
 
 
 1
 190
 
 190
37
 
 
 1
 38
 
 38
Production(48) 
 (8) (1) (4) (61) 
 (61)(48) (8) (1) (4) (61) 
 (61)
Sales of reserves in place(77) 
 
 
 
 (77) 
 (77)(77) 
 
 
 (77) 
 (77)
End of year - 2016563
 
 45
 172
 22
 802
 
 802
563
 45
 172
 22
 802
 
 802
Revisions of previous estimates9
 (2) 
 8
 15
 
 15
Improved recovery
 
 
 
 
 
 
Purchases of reserves in place18
 
 
 
 18
 
 18
Extensions, discoveries and             
other additions30
 4
 
 
 34
 
 34
Production(49) (8) (7) (4) (68) 
 (68)
Sales of reserves in place(1) 
 
 
 (1) 
 (1)
End of year - 2017570
 39
 165
 26
 800
 
 800
Proved developed reserves:                            
Beginning of year - 2014241
 
 37
 176
 19
 473
 77
 550
End of year - 2014294
 
 30
 175
 19
 518
 
 518
Beginning of year - 2015294
 30
 175
 19
 518
 
 518
End of year - 2015327
 
 25
 173
 16
 541
 
 541
327
 25
 173
 16
 541
 
 541
End of year - 2016238
 
 45
 172
 13
 468
 
 468
238
 45
 172
 13
 468
 
 468
End of year - 2017263
 39
 165
 17
 484
 
 484
Proved undeveloped reserves:                            
Beginning of year - 2014256
 
 27
 39
 6
 328
 14
 342
End of year - 2014340
 
 27
 33
 10
 410
 
 410
Beginning of year - 2015340
 27
 33
 10
 410
 
 410
End of year - 2015253
 
 27
 28
 6
 314
 
 314
253
 27
 28
 6
 314
 
 314
End of year - 2016325
 
 
 
 9
 334
 
 334
325
 
 
 9
 334
 
 334
End of year - 2017307
 
 
 9
 316
 
 316
 













Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves (continued)
(mmbbl)U.S. Canada 
E.G.(a)
 
Other
Africa
 Other Int'l Cont Ops Disc Ops TotalU.S. 
E.G.(a)
 Libya Other Int'l Cont Ops Disc Ops Total
Natural gas liquids                            
Proved developed and undeveloped reserves:
Beginning of year - 2014119
 
 34
 
 1
 154
 
 154
Revisions of previous estimates4
 
 
 
 
 4
 
 4
Improved recovery
 
 
 
 
 
 
 
Purchases of reserves in place1
 
 
 
 
 1
 
 1
Extensions, discoveries and        

 

   

other additions48
 
 
 
 
 48
 
 48
Production(11) 
 (4) 
 
 (15) 
 (15)
Sales of reserves in place
 
 
 
 
 
 
 
End of year - 2014161
 
 30
 
 1
 192
 
 192
Beginning of year - 2015161
 30
 
 1
 192
 
 192
Revisions of previous estimates(31) 
 2
 
 (1) (30) 
 (30)(7) 2
 
 (1) (6) 
 (6)
Improved recovery
 
 
 
   
 
 

 
 
 
 
 
 
Purchases of reserves in place
 
 
 
 
 
 
 

 
 
 
 
 
 
Extensions, discoveries and        

 

   

             
other additions57
 
 
 
 
 57
 
 57
33
 
 
 
 33
 
 33
Production(14) 
 (4) 
 
 (18) 
 (18)(14) (4) 
 
 (18) 
 (18)
Sales of reserves in place(1) 
 
 
 
 (1) 
 (1)(1) 
 
 
 (1) 
 (1)
End of year - 2015172
 

28





200



200
172
 28
 
 
 200
 
 200
Revisions of previous estimates(51) 
 
 
 
 (51) 
 (51)(8) 
 
 
 (8) 
 (8)
Improved recovery
 
 
 
 
 
 
 

 
 
 
 
 
 
Purchases of reserves in place12
 
 
 
 
 12
 
 12
12
 
 
 
 12
 
 12
Extensions, discoveries and        

 

   

             
other additions54
 
 
 
 
 54
 
 54
11
 
 
 
 11
 
 11
Production(14) 
 (4) 
 
 (18) 
 (18)(14) (4) 
 
 (18) 
 (18)
Sales of reserves in place(3) 
 
 
 
 (3) 
 (3)(3) 
 
 
 (3) 
 (3)
End of year - 2016170
 
 24
 
 
 194
 
 194
170
 24
 
 
 194
 
 194
Revisions of previous estimates37
 3
 
 
 40
 
 40
Improved recovery
 
 
 
 
 
 
Purchases of reserves in place5
 
 
 
 5
 
 5
Extensions, discoveries and             
other additions34
 2
 
 
 36
 
 36
Production(16) (4) 
 
 (20) 
 (20)
Sales of reserves in place(1) 
 
 
 (1) 
 (1)
End of year - 2017229
 25
 
 
 254
 
 254
Proved developed reserves:                            
Beginning of year - 201451
 
 18
 
 1
 70
 
 70
End of year - 201468
 
 15
 
 
 83
 
 83
Beginning of year - 201568
 15
 
 
 83
 
 83
End of year - 201592
 
 12
 
 
 104
 
 104
92
 12
 
 
 104
 
 104
End of year - 201678
 
 24
 
 
 102
 
 102
78
 24
 
 
 102
 
 102
End of year - 2017118
 25
 
 
 143
 
 143
Proved undeveloped reserves:                            
Beginning of year - 201468
 
 16
 
 
 84
 
 84
End of year - 201493
 
 15
 
 1
 109
 
 109
Beginning of year - 201593
 15
 
 1
 109
 
 109
End of year - 201580
 
 16
 
 
 96
 
 96
80
 16
 
 
 96
 
 96
End of year - 201692
 
 
 
 
 92
 
 92
92
 
 
 
 92
 
 92
End of year - 2017111
 
 
 
 111
 
 111





Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves (continued)

(bcf)U.S. Canada 
E.G.(a)
 
Other
Africa
 Other Int'l Cont Ops Disc Ops Total
Natural gas               
Proved developed and undeveloped reserves:
Beginning of year - 20141,025
 
 1,320
 205
 28
 2,578
 93
 2,671
Revisions of previous estimates(24) 
 1
 5
 2
 (16) 7
 (9)
Improved recovery
 
 
 
 
 
 
 
Purchases of reserves in place5
 
 
 
 
 5
 
 5
Extensions, discoveries and        

 

   

other additions290
 
 44
 
 
 334
 2
 336
Production(b)
(113) 
 (160) (1) (8) (282) (13) (295)
Sales of reserves in place(39) 
 
 
 
 (39) (89) (128)
End of year - 20141,144
 
 1,205
 209
 22
 2,580
 
 2,580
Revisions of previous estimates(191) 
 35
 (3) 1
 (158) 
 (158)
Improved recovery
 
 
 
 
 
 
 
Purchases of reserves in place1
 
 
 
 
 1
 
 1
Extensions, discoveries and        

 

   

other additions394
 
 
 
 
 394
 
 394
Production(b)
(128) 
 (150) 
 (8) (286) 
 (286)
Sales of reserves in place(69) 
 
 
 
 (69) 
 (69)
End of year - 20151,151
 
 1,090
 206
 15
 2,462
 
 2,462
Revisions of previous estimates(146) 
 8
 (1) 3
 (136) 
 (136)
Improved recovery
 
 
 
 
 
 
 
Purchases of reserves in place61
 
 
 
 
 61
 
 61
Extensions, discoveries and        

 

   

other additions362
 
 
 
 
 362
 
 362
Production(b)
(115) 
 (155) 
 (8) (278) 
 (278)
Sales of reserves in place(25) 
 
 
 
 (25) 
 (25)
End of year - 20161,288
 
 943
 205
 10
 2,446
 
 2,446
Proved developed reserves:              
Beginning of year - 2014540
 
 823
 95
 21
 1,479
 20
 1,499
End of year - 2014575
 
 664
 94
 17
 1,350
 
 1,350
End of year - 2015640
 
 552
 94
 11
 1,297
 
 1,297
End of year - 2016648
 
 943
 95
 5
 1,691
 ���
 1,691
Proved undeveloped reserves:              
Beginning of year - 2014485
 
 497
 110
 7
 1,099
 73
 1,172
End of year - 2014569
 
 541
 115
 5
 1,230
 
 1,230
End of year - 2015511
 
 538
 112
 4
 1,165
 
 1,165
End of year - 2016640
 
 
 110
 5
 755
 
 755







Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves (continued)
(mmbbl)U.S. Canada 
E.G.(a)
 
Other
Africa
 Other Int'l Cont Ops Disc Ops Total
Synthetic crude oil               
(bcf)U.S. 
E.G.(a)
 Libya Other Int'l Cont Ops Disc Ops Total
Natural gas             
Proved developed and undeveloped reserves:
Beginning of year - 2014
 680
 
 
 
 680
 
 680
Beginning of year - 20151,144
 1,205
 209
 22
 2,580
 
 2,580
Revisions of previous estimates
 (55) 
 
 
 (55) 
 (55)(22) 35
 (3) 1
 11
 
 11
Improved recovery
 
 
 
 
 
 
 

 
 
 
 
 
 
Purchases of reserves in place
 38
 
 
 
 38
 
 38
1
 
 
 
 1
 
 1
Extensions, discoveries and                            
other additions
 
 
 
 
 
 
 
225
 
 
 
 225
 
 225
Production
 (15) 
 
 
 (15) 
 (15)
Sales of reserves in place
 
 
 
 
 
 
 
End of year - 2014
 648
 
 
 
 648
 
 648
Revisions of previous estimates
 67
 
 
 
 67
 
 67
Improved recovery
 
 
 
 
 
 
 
Purchases of reserves in place
 
 
 
 
 
 
 
Extensions, discoveries and               
other additions
 
 
 
 
 
 
 
Production
 (17) 
 
 
 (17) 
 (17)
Production (b)
(128) (150) 
 (8) (286) 
 (286)
Sales of reserves in place
 
 
 
 
 
 
 
(69) 
 
 
 (69) 
 (69)
End of year - 2015
 698
 
 
 
 698
 
 698
1,151
 1,090
 206
 15
 2,462
 
 2,462
Revisions of previous estimates
 12
 
 
 
 12
 
 12
145
 8
 (1) 3
 155
 
 155
Improved recovery
 
 
 
 
 
 
 

 
 
 
 
 
 
Purchases of reserves in place
 
 
 
 
 
 
 
61
 
 
 
 61
 
 61
Extensions, discoveries and              
             
other additions
 
 
 
     
 
71
 
 
 
 71
 
 71
Production
 (18) 
 
 
 (18) 
 (18)
Production (b)
(115) (155) 
 (8) (278) 
 (278)
Sales of reserves in place
 
 
 
 
 
 
 
(25) 
 
 
 (25) 
 (25)
End of year - 2016
 692
 
 
 
 692
 
 692
1,288
 943
 205
 10
 2,446
 
 2,446
Revisions of previous estimates(33) (18) 
 4
 (47) 
 (47)
Improved recovery
 
 
 
 
 
 
Purchases of reserves in place36
 
 
 
 36
 
 36
Extensions, discoveries and             
other additions204
 76
 
 
 280
 
 280
Production (b)
(127) (168) (1) (6) (302) 
 (302)
Sales of reserves in place(44) 
 
 
 (44) 
 (44)
End of year - 20171,324
 833
 204
 8
 2,369
 
 2,369
Proved developed reserves:                            
Beginning of year - 2014
 674
 
 
 
 674
 
 674
End of year - 2014
 644
 
 
 
 644
 
 644
Beginning of year - 2015575
 664
 94
 17
 1,350
 
 1,350
End of year - 2015
 698
 
 
 
 698
 
 698
640
 552
 94
 11
 1,297
 
 1,297
End of year - 2016
 692
 
 
 
 692
 
 692
648
 943
 95
 5
 1,691
 
 1,691
End of year - 2017726
 833
 94
 2
 1,655
 
 1,655
Proved undeveloped reserves:                            
Beginning of year - 2014
 
 
 
 
 
 
 
End of year - 2014
 4
 
 
 
 4
 
 4
Beginning of year - 2015569
 541
 115
 5
 1,230
 
 1,230
End of year - 2015
 
 
 
 
 
 
 
511
 538
 112
 4
 1,165
 
 1,165
End of year - 2016
 
 
 
 
 
 
 
640
 
 110
 5
 755
 
 755
End of year - 2017598
 
 110
 6
 714
 
 714














Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves (continued)
(mmboe)U.S. Canada 
E.G.(a)
 
Other
Africa
 Other Int'l Cont Ops Disc Ops Total
Total Proved Reserves               
(mmbbl)U.S. 
E.G.(a)
 Libya Other Int'l Cont Ops Disc Ops Total
Synthetic crude oil             
Proved developed and undeveloped reserves:
Beginning of year - 2014787
 680
 318
 249
 31
 2,065
 106
 2,171
Beginning of year - 2015
 
 
 
 
 648
 648
Revisions of previous estimates36
 (55) 
 (3) 
 (22) 11
 (11)
 
 
 
 
 67
 67
Improved recovery2
 
 
 
 
 2
 
 2

 
 
 
 
 
 
Purchases of reserves in place8
 38
 
 
 
 46
 
 46

 
 
 
 
 
 
Extensions, discoveries and        

 

   

             
other additions250
 
 8
 
 7
 265
 3
 268

 
 
 
 
 
 
Production(b)
(87) (15) (38) (3) (5) (148) (19) (167)
Sales of reserves in place(10) 
 
 
   (10) (101) (111)
End of year - 2014986
 648
 288
 243
 33
 2,198
 
 2,198
Revisions of previous estimates(173) 67
 8
 (8) (2) (108) 
 (108)
Improved recovery1
 
 
 
 
 1
 
 1
Purchases of reserves in place1
 
 
 
 
 1
 
 1
Extensions, discoveries and        

 

   
other additions245
 
 1
 
 
 246
 
 246
Production(b)
(98) (17) (36) 
 (6) (157) 
 (157)
Production
 
 
 
 
 (17) (17)
Sales of reserves in place(18) 
 
 
 
 (18) 
 (18)
 
 
 
 
 
 
End of year - 2015944
 698
 261
 235
 25
 2,163
 
 2,163

 
 
 
 
 698
 698
Revisions of previous estimates(171) 12
 2
 (28) 4
 (181) 
 (181)
 
 
 
 
 12
 12
Improved recovery4
 
 
 
 
 4
 
 4

 
 
 
 
 
 
Purchases of reserves in place34
 
 
 
 
 34
 
 34

 
 
 
 
 
 
Extensions, discoveries and        

 

   

             
other additions303
 
 
 
 1
 304
 
 304

 
 
 
 
 
 
Production(b)
(82) (18) (37) (1) (6) (144) 
 (144)
Production
 
 
 
 
 (18) (18)
Sales of reserves in place(84) 
 
 
 
 (84) 
 (84)
 
 
 
 
 
 
End of year - 2016948
 692

226

206

24
 2,096
 

2,096

 
 
 
 
 692
 692
Revisions of previous estimates
 
 
 
 
 
 
Improved recovery
 
 
 
 
 
 
Purchases of reserves in place
 
 
 
 
 
 
Extensions, discoveries and             
other additions
 
 
 
 
 
 
Production
 
 
 
 
 (7) (7)
Sales of reserves in place
 
 
 
 
 (685) (685)
End of year - 2017
 
 
 
 
 
 
Proved developed reserves:                            
Beginning of year - 2014382
 674
 193
 192
 23
 1,464
 80
 1,544
End of year - 2014458
 644
 155
 191
 22
 1,470
 
 1,470
Beginning of year - 2015
 
 
 
 
 644
 644
End of year - 2015526
 698
 129
 189
 18
 1,560
 
 1,560

 
 
 
 
 698
 698
End of year - 2016424
 692
 226
 188
 14
 1,544
 
 1,544

 
 
 
 
 692
 692
End of year - 2017
 
 
 
 
 
 
Proved undeveloped reserves:              
             
Beginning of year - 2014405
 6
 125
 57
 8
 601
 26
 627
End of year - 2014528
 4
 133
 52
 11
 728
 
 728
Beginning of year - 2015
 
 
 
 
 4
 4
End of year - 2015418
 
 132
 46
 7
 603
 
 603

 
 
 
 
 
 
End of year - 2016524
 
 
 18
 10
 552
 
 552

 
 
 
 
 
 
End of year - 2017
 
 
 
 
 
 
















Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Estimated Quantities of Proved Oil and Gas Reserves (continued)
(mmboe)U.S. 
E.G.(a)
 Libya Other Int'l Cont Ops Disc Ops Total
Total Proved Reserves             
Proved developed and undeveloped reserves:
Beginning of year - 2015986
 288
 243
 33
 1,550
 648
 2,198
Revisions of previous estimates(67) 8
 (8) (2) (69) 67
 (2)
Improved recovery1
 
 
 
 1
 
 1
Purchases of reserves in place1
 
 
 
 1
 
 1
Extensions, discoveries and             
other additions139
 1
 
 
 140
 
 140
Production (b)
(98) (36) 
 (6) (140) (17) (157)
Sales of reserves in place(18) 
 
 
 (18) 
 (18)
End of year - 2015944
 261
 235
 25
 1,465
 698
 2,163
Revisions of previous estimates73
 2
 (28) 4
 51
 12
 63
Improved recovery4
 
 
 
 4
 
 4
Purchases of reserves in place34
 
 
 
 34
 
 34
Extensions, discoveries and             
other additions59
 
 
 1
 60
 
 60
Production (b)
(82) (37) (1) (6) (126) (18) (144)
Sales of reserves in place(84) 
 
 
 (84) 
 (84)
End of year - 2016948
 226
 206
 24
 1,404
 692
 2,096
Revisions of previous estimates42
 (1) 
 8
 49
 
 49
Improved recovery
 
 
 
 
 
 
Purchases of reserves in place28
 
 
 
 28
 
 28
Extensions, discoveries and             
other additions98
 18
 
 
 116
 
 116
Production (b)
(86) (40) (7) (5) (138) (7) (145)
Sales of reserves in place(10) 
 
 
 (10) (685) (695)
End of year - 20171,020
 203
 199
 27
 1,449
 
 1,449
Proved developed reserves:             
Beginning of year - 2015458
 155
 191
 22
 826
 644
 1,470
End of year - 2015526
 129
 189
 18
 862
 698
 1,560
End of year - 2016424
 226
 188
 14
 852
 692
 1,544
End of year - 2017502
 203
 181
 17
 903
 
 903
Proved undeveloped reserves:             
Beginning of year - 2015528
 133
 52
 11
 724
 4
 728
End of year - 2015418
 132
 46
 7
 603
 
 603
End of year - 2016524
 
 18
 10
 552
 
 552
End of year - 2017518
 
 18
 10
 546
 
 546

(a) 
Consists of estimated reserves from properties governed by production sharing contracts.
(b) 
Excludes the resale of purchased natural gas used in reservoir management.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


2017 proved reserves decreased by 647 mmboe primarily due to the following:
Revisions of previous estimates: Increased by 49 mmboe primarily due to the acceleration of higher economic wells in the Bakken into the 5-year plan resulting in an increase of 44 mmboe, with the remainder being due to revisions across the business.
Extensions, discoveries, and other additions: Increased by 116 mmboe primarily due to an increase of 97 mmboe associated with the expansion of proved areas and wells to sales from unproved categories in Oklahoma.
Purchases of reserves in place: Increased by 28 mmboe from acquisitions of assets in the Northern Delaware Basin in New Mexico.
Production: Decreased by 145 mmboe.
Sales of reserves in place: Decreased by 695 mmboe including 685 mmboe associated with the sale of our Canadian business and 10 mmboe associated with divestitures of certain conventional assets in Oklahoma and Colorado. See Item 8. Financial Statements and Supplementary Data - Note 5 to the consolidated financial statements for information regarding these dispositions.

2016 proved reserves decreased by 67 mmboe primarily due to the following:
Revisions of previous estimates: DecreaseIncreased by 63 mmboe primarily due to an increase of 181151 mmboe due primarily to 93 mmboe of revision associated with the deferralacceleration of lowerhigher economic value wells in the U.S. unconventional resource plays outside ofinto the 5-year plan and a decrease of 64 mmboe due to U.S. technical reevaluations.revisions.
Extensions, discoveries, and other additions: Increased by 30860 mmboe primarily in our U.S unconventional resource plays associated with the acceleration of higher economic wells into the 5-year plan, the expansion of proved areas in Oklahoma, and new wells to sales from unproved categories.unproven categories in Oklahoma.
Purchases of reserves in place: AcquisitionIncreased by 34 mmboe from acquisition of STACK assets in Oklahoma.
Production: Decrease ofDecreased by 144 mmboe.
Sales of reserves in place: Decrease ofDecreased by 84 mmboe associated with the divestitures of ourcertain Wyoming and certain Gulf of Mexico assets. See Item 8. Financial Statements and Supplementary Data - Note 6 to the consolidated financial statements for information regarding these dispositions.

2015 total proved reserves decreased by 35 mmboe primarily due to the following:
Revisions of previous estimates: DecreaseDecreased by 2 mmboe primarily resulting from an increase of 105 mmboe associated with drilling programs in U.S. resource plays and an increase of 67 mmboe in discontinued operations due to technical reevaluation and lower royalty percentages related to lower realized prices, offset by a decrease of 173 mmboe which was largely due to reductions to our capital development program and adherence to the SEC 5-year rule and partially offset by a positive revision of 67 mmboe in OSM due to technical reevaluation and lower royalty percentages related to lower realized prices. Royalties paid in Canada are determined on a progressive scale; as the sales price of our synthetic crude oil rises, the royalty rate rises as well.rule.
Extensions, discoveries, and other additions: Increased 245by140 mmboe as a result of drilling programs in our U.S. resource plays.
Production: Decrease ofDecreased by 157 mmboe.
Sales of reserves in place: U.S. conventional assets sales contributed to a decrease of 18 mmboe.

2014 total proved reserves increased by 27 mmboe primarily due to the following:
Revisions of previous estimates: Negative revisions of 55 mmboe to OSM synthetic crude oil reserves were impacted by technical changes, calculation of estimated royalty volumes, and development plan changes in mineable areas. This downward revision was offset by positive revisions from U.S. resource play development activity.
Extensions, discoveries, and other additions: Increased 250 mmboe primarily as a result of development activity in the U.S.
Production: Decrease of 167 mmboe.
Sales of reserves in place: Decrease of 101 mmboe primarily related to the sale of our assets in Norway and Angola (reflected in discontinued operations).
Changes in Proved Undeveloped Reserves
As of December 31, 2016, 5522017, 546 mmboe of proved undeveloped reserves were reported, a decrease of 516 mmboe from December 31, 2015.2016. The following table shows changes in total proved undeveloped reserves for 2016:2017:
(mmboe) 
Beginning of year603552
Revisions of previous estimates(1445)
Improved recovery4
Purchases of reserves in place2015
Extensions, discoveries, and other additions26457
Dispositions(14)
Transfers to proved developed(18183)
End of year552546
Revisions of prior estimatesestimates.. Revisions of prior estimates decreased 144increased 5 mmboe during 2016. Over half of this revision, 93 mmboe, was2017, primarily due to deferrala 44 mmboe increase in the Bakken from an acceleration of lowerhigher economic value wells beyondinto the 5-year window. The remaining revisions were drivenplan, offset by well performance dominated by lower secondary product volumes, which includes reduction in NGL reserves associated with ethane rejection, recognitiona decrease of lower than expected performance from high density wells in Eagle Ford and various wells40 mmboe in Oklahoma anddue to the removal of capital commitmentless economic wells from two long-term international projects.the 5-year plan.
Extensions, discoveries and other additions.Increased264 57 mmboe through higher planned activity levels in the U.S. resource plays, expansion of proved areas in Oklahoma, and acceleration of higher economic value wells into the 5-year plan.Oklahoma.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Transfers to proved developed. 18183 mmboe of PUD reserves were converted to proved developed status during 2016, of which 134 mmboe is associated with the E.G. Alba compression project.2017, primarily from assets in our U.S. resource plays. This 20162017 transfer equates to a 30%15% PUD conversion rate. Ourrate and a 5-year average annual PUD conversion rate during 2012-2016the 2013-2017 period is 19% and would be 28% if the long-term projects in E.G. and Libya are excluded.of 18%. All proved undeveloped reserve drilling locations are scheduled to be drilled prior to the end of 2021. No material volumes2022.
A total of 25 mmboe of proved undeveloped reserves, or less than 2% of the company’s total proved reserves, have been on the books beyond 5 years as of year-end 2016.2017.
As of year-end 2017, there were 18 mmboe of proved undeveloped reserves, initially disclosed in 2012, associated with the Faregh Phase II project in Libya. Drilling operations and construction of the associated gas plant were completed in 2010. Final commissioning was halted in 2011 and again in 2013 due to civil unrest and subsequent declaration of Force Majeure.  In 2017, teams conducted an assessment of the facilities to determine the state of the equipment and developed a plan to recommission the plant and initiate production in 2018, at which time, all associated proved undeveloped reserves will be transferred to proved developed.
As of year-end 2017, there were 7 mmboe of proved undeveloped reserves, initially disclosed in 2011, associated with the Fuel Gas Deficiency project in the U.K. The project includes the design, procurement and installation of the Brae Bravo gas by-pass, which will ensure continued operations at the existing Brae Alpha and East Brae platforms. The project has been approved and work is underway with completion expected in 2018, at which time, all associated proved undeveloped reserves will be transferred to proved developed.
Costs Incurred & Future Costs to Develop
Costs incurred in 2017, 2016 2015 and 20142015 relating to the development of proved undeveloped reserves were $842 million, $359 million $1,415 million and $3,149$1,415 million. As of December 31, 2016,2017, future development costs estimated to be required for the development of proved undeveloped crude oil and condensate, NGLs and natural gas and synthetic crude oil reserves for the years 20172018 through 20212022 are projected to be $784$1,425 million, $1,134$1,348 million, $1,665$1,409 million, $1,847$1,458 million and $809$1,028 million.

Capitalized Costs and Accumulated Depreciation, Depletion and Amortization
 Year Ended December 31,
(In millions)U.S. Canada E.G. 
Other
Africa
 Other Int'l Total
2016 Capitalized Costs:           
Proved properties$25,497
 $9,571
 $1,978
 $756
 $5,864
 $43,666
Unproved properties1,473
 1,379
 119
 417
 183
 3,571
Total26,970
 10,950
 2,097
 1,173
 6,047
 47,237
Accumulated depreciation,           
depletion and amortization:           
Proved properties12,526
 1,649
 1,216
 269
 5,246
 20,906
Unproved properties (a)
382
 310
 2
 
 113
 807
Total12,908
 1,959
 1,218
 269
 5,359
 21,713
Net capitalized costs$14,062
 $8,991
 $879
 $904
 $688
 $25,524
2015 Capitalized Costs:           
Proved properties$27,816
 $9,538
 $1,955
 $828
 $5,741
 $45,878
Unproved properties1,625
 1,389
 86
 465
 242
 3,807
Total29,441
 10,927
 2,041
 1,293
 5,983
 49,685
Accumulated depreciation,           
depletion and amortization:           
Proved properties13,656
 1,420
 1,105
 263
 5,195
 21,639
Unproved properties (a)
675
 310
 
 107
 114
 1,206
Total14,331
 1,730
 1,105
 370
 5,309
 22,845
Net capitalized costs$15,110
 $9,197
 $936
 $923
 $674
 $26,840
 Year Ended December 31,
(In millions)U.S. E.G. Libya Other Africa Other Int'l Total
2017 Capitalized Costs:           
Proved properties$27,477
 $1,990
 830
 $
 $5,050
 $35,347
Unproved properties2,755
 110
 217
 43
 33
 3,158
Total30,232
 2,100
 1,047
 43
 5,083
 38,505
Accumulated depreciation,          
depletion and amortization:          
Proved properties14,254
 1,348
 289
 
 4,850
 20,741
Unproved properties (a)
206
 
 
 43
 33
 282
Total14,460
 1,348
 289
 43
 4,883
 21,023
Net capitalized costs$15,772
 $752
 $758
 $
 $200
 $17,482
2016 Capitalized Costs:          
Proved properties$25,497
 $1,978
 $756
 $
 $5,864
 $34,095
Unproved properties1,473
 119
 281
 136
 183
 2,192
Total26,970
 2,097
 1,037
 136
 6,047
 36,287
Accumulated depreciation,          
depletion and amortization:          
Proved properties12,526
 1,216
 268
 1
 5,246
 19,257
Unproved properties (a)
382
 2
 
 
 113
 497
Total12,908
 1,218
 268
 1
 5,359
 19,754
Net capitalized costs$14,062
 $879
 $769
 $135
 $688
 $16,533
(a) Includes unproved property impairments (see Note 13)10).


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Costs Incurred for Property Acquisition, Exploration and Development (a) 
(In millions)U.S. Canada E.G. 
Other
Africa
 Other Int'l Cont Ops Disc Ops TotalU.S. E.G. Libya 
Other
Africa
 Other Int'l Cont Ops Disc Ops Total
December 31, 2017               
Property acquisition:               
Proved$191
 $1
 $
 $
 $
 $192
 $
 $192
Unproved1,746
 
 
 1
 
 1,747
 
 1,747
Exploration882
 1
 
 37
 3
 923
 
 923
Development1,122
 5
 10
 
 (144)
(b) 
993
 6
 999
Total$3,941
 $7
 $10
 $38
 $(141) $3,855
 $6
 $3,861
December 31, 2016                              
Property acquisition:                              
Proved$276
 $
 $
 $
 $
 $276
 $
 $276
$276
 $
 $
 $
 $
 $276
 $
 $276
Unproved642
 
 
 1
 (11) 632
 
 632
642
 
 
 1
 (11) 632
 
 632
Exploration525
 
 1
 10
 3
 539
 
 539
525
 1
 
 10
 3
 539
 
 539
Development456
 31
 55
 3
 121
(c) 
666
 
 666
456
 55
 3
 
 121
(b) 
635
 31
 666
Total$1,899
 $31
 $56
 $14
 $113
 $2,113
 $
 $2,113
$1,899
 $56
 $3
 $11
 $113
 $2,082
 $31
 $2,113
December 31, 2015                              
Property acquisition:                              
Proved$4
 $
 $
 $
 $
 $4
 $
 $4
$4
 $
 $
 $
 $
 $4
 $
 $4
Unproved61
 
 
 1
 
 62
 
 62
61
 
 
 1
 
 62
 
 62
Exploration959
 1
 60
 38
 50
 1,108
 
 1,108
959
 60
 1
 37
 50
 1,107
 1
 1,108
Development1,477
 
 150
 13
 31
(c) 
1,671
 
 1,671
1,477
 150
 13
 
 31
 1,671
 
 1,671
Total$2,501
 $1
(b) 
$210
 $52
 $81
 $2,845
 $
 $2,845
$2,501
 $210
 $14
 $38
 $81
 $2,844
 $1
 $2,845
December 31, 2014               
Property acquisition:               
Proved$26
 $
 $
 $
 $
 $26
 $
 $26
Unproved202
 3
 
 53
 2
 260
 1
 261
Exploration1,140
 4
 35
 119
 119
 1,417
 6
 1,423
Development3,532
 196
 139
 16
 94
 3,977
 418
 4,395
Total$4,900
 $203
 $174
 $188
 $215
 $5,680
 $425
 $6,105
(a) 
Includes costs incurred whether capitalized or expensed. 
(b) 
Reflects reimbursements earned from the governments of Canada and Alberta related to funds previously expended for Quest CCS capital equipment.
(c)
Includes revisions to asset retirement costs primarily due to changes in U.K. estimated costs as well as timing of theseabandonment activities in the U.K.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Results of Operations for Oil and Gas Producing Activities
U.S. Canada E.G. 
Other
Africa
 Other Int'l Cont Ops Disc Ops TotalU.S. E.G. Libya 
Other
Africa
 Other Int'l Cont Ops Disc Ops Total
Year Ended December 31, 2016               
Year Ended December 31, 2017               
Revenues and other income:                              
Sales$2,249
 $724
 $42
 $54
 $237
 $3,306
 $
 $3,306
$3,050
 $45
 $431
 $
 $282
 $3,808
 $423
 $4,231
Transfers
 
  291
 
 
 291
 
 291

 344
 
 
 
 344
 
 344
Other income(a)
387
 
  
 
 2
 389
 
 389
74
 
 
 
 38
 112
 (43) 69
Total revenues and other income2,636
 724
 333
 54
 239
 3,986
 
 3,986
3,124
 389
 431
 
 320
 4,264
 380
 4,644
Expenses:                         
    
Production costs(952) (544) (81) (36) (140) (1,753) 
 (1,753)(985) (84) (44) 
 (152) (1,265) (272) (1,537)
Exploration expenses(b)
(306) (7) (1) (14) (2) (330) 
 (330)(153) 
 
 (171) (83) (407) 
 (407)
Depreciation, depletion and        

              

 

    
amortization(c)
(1,901) (239) (114) (7) (132) (2,393) 
 (2,393)(2,105) (134) (21) 
 (273) (2,533) (6,676) (9,209)
Technical support and other(21) (1) (4) (3) (2) (31) 
 (31)(28) (4) (4) (7) (18) (61) 
 (61)
Total expenses(3,180) (791) (200) (60) (276) (4,507) 
 (4,507)(3,271) (222) (69) (178) (526) (4,266) (6,948) (11,214)
Results before income taxes(544) (67) 133
 (6) (37) (521) 
 (521)(147) 167
 362
 (178) (206) (2) (6,568) (6,570)
Income tax provision195
 15
 (26) (2) 57
 239
 
 239
(1) (50) (333) 
 13
 (371) 1,674
 1,303
Results of operations$(349) $(52) $107
 $(8) $20
 $(282) $
 $(282)$(148) $117
 $29
 $(178) $(193) $(373) $(4,894) $(5,267)
Year Ended December 31, 2015               
Year Ended December 31, 2016          
    
Revenues and other income:                         
    
Sales$3,374
 $700
 $40
 $
 $329
 $4,443
 $
 $4,443
$2,249
 $42
 $54
 $
 $237
 $2,582
 $724
 $3,306
Transfers
 
  296
 
 
 296
 
 296

 291
 
 
 
 291
 
 291
Other income(a)
230
 
  
 (109) 1
 122
 
 122
387
 
 
 
 2
 389
 
 389
Total revenues and other income3,604
 700
 336
 (109) 330
 4,861
 
 4,861
2,636
 333
 54
 
 239
 3,262
 724
 3,986
Expenses:              
          
   
Production costs(1,259) (660) (84) (31) (177) (2,211) 
 (2,211)(952) (81) (36) 
 (140) (1,209) (544) (1,753)
Exploration expenses(b)
(750) (348) (41) (36) (143) (1,318) 
 (1,318)(306) (1) (6) (8) (2) (323) (7) (330)
Depreciation, depletion and        

 

            

 

    
amortization(c)
(2,758) (266) (92) (5) (163) (3,284) 
 (3,284)(1,901) (114) (7) 
 (132) (2,154) (239) (2,393)
Technical support and other(47) (2) (6) (2) (3) (60) 
 (60)(21) (4) 
 (3) (2) (30) (1) (31)
Total expenses(4,814) (1,276) (223) (74) (486) (6,873) 
 (6,873)(3,180) (200) (49) (11) (276) (3,716) (791) (4,507)
Results before income taxes(1,210) (576) 113
 (183) (156) (2,012) 
 (2,012)(544) 133
 5
 (11) (37) (454) (67) (521)
Income tax provision (d)
437
 31
 (33) 87
 86
 608
 
 608
195
 (26) (2) 
 57
 224
 15
 239
Results of operations$(773) $(545) $80
 $(96) $(70) $(1,404) $
 $(1,404)$(349) $107
 $3
 $(11) $20
 $(230) $(52) $(282)
Year Ended December 31, 2014               
Year Ended December 31, 2015          
    
Revenues and other income:                         
    
Sales$5,754
 $1,316
 $43
 $244
 $440
 $7,797
 $189
 $7,986
$3,374
 $40
 $
 $
 $329
 $3,743
 $700
 $4,443
Transfers3
 
  588
 
 3
 594
 1,848
 2,442

 296
 
 
 
 296
 
 296
Other income(a)
(85) 
  
 
 
 (85) 1,832
 1,747
230
 
 
 (109) 1
 122
 
 122
Total revenues and other income5,672
 1,316
 631
 244
 443
 8,306
 3,869
 12,175
3,604
 336
 
 (109) 330
 4,161
 700
 4,861
Expenses:              
          
   
Production costs(1,544) (803) (154) (79) (253) (2,833) (181) (3,014)(1,259) (84) (31) 
 (177) (1,551) (660) (2,211)
Exploration expenses(b)
(607) (1) (26) (103) (56) (793) (5) (798)(750) (41) 
 (36) (143) (970) (348) (1,318)
Depreciation, depletion and        

 

   
        

 

   

amortization(c)
(2,474) (206) (93) (9) (115) (2,897) (105) (3,002)(2,758) (92) (5) 
 (163) (3,018) (266) (3,284)
Technical support and other(193) (15) (31) (21) (14) (274) (7) (281)(47) (6) (1) (1) (3) (58) (2) (60)
Total expenses(4,818) (1,025) (304) (212) (438) (6,797) (298) (7,095)(4,814) (223) (37) (37) (486) (5,597) (1,276) (6,873)
Results before income taxes854
 291
 327
 32
 5
 1,509
 3,571
 5,080
(1,210) 113
 (37) (146) (156) (1,436) (576) (2,012)
Income tax provision(302) (71) (117) (32) (18) (540) (1,496) (2,036)437
 (33) 37
 50
 86
 577
 31
 608
Results of operations$552
 $220
 $210
 $
 $(13) $969
 $2,075
 $3,044
$(773) $80
 $
 $(96) $(70) $(859) $(545) $(1,404)


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


(a) 
Includes net gain (loss) on dispositions (see Note 6).5) and revisions to asset retirement costs primarily due to changes in U.K. estimated costs as well as timing of abandonment activities in the U.K.
(b) 
Includes exploratory dry well costs, unproved property impairments, and other (see Note 13)10).
(c) 
Includes long-lived asset impairments (see Note 13)10).
(d)    IncludesDiscontinued operations activity includes $135 million of deferred tax expense related to Alberta provincial corporate tax rate increase (see Note 9).increase.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Results of Operations for Oil and Gas Producing Activities
The following reconciles results of operations for oil and gas producing activities to segment income:
Year Ended December 31,Year Ended December 31,
(In millions)2016 2015 20142017 2016 2015
Results of operations$(282) $(1,404) $3,044
$(5,267) $(282) $(1,404)
Discontinued operations
 
 (2,075)4,894
 52
 545
Results of continuing operations(282) (1,404) 969
(373) (230) (859)
Items not included in results of oil and gas operations, net of tax:          
Marketing income and other non-oil and gas producing related activities(43) (75) 73
(107) (39) (102)
Income from equity method investments142
 127
 327
229
 142
 127
Items not allocated to segment income, net of tax:          
Loss (gain) on asset dispositions(248) (57) 58
Loss (gain) on asset dispositions and other income(79) (248) (76)
Long-lived asset impairments149
 819
 69
475
 148
 602
Unrealized loss (gain) on derivatives72
 (32) 
81
 72
 (32)
Alberta provincial corporate tax rate increase
 135
 
Foreign tax valuation allowance increase(32) 
 
Deferred tax valuation allowance increase
 (32) 
Segment income$(242) $(487) $1,496
$226
 $(187) $(340)


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Standardized Measure of Discounted Future Net Cash Flows Relating to Proved Reserves
U.S. GAAP prescribes guidelines for computing the standardized measure of future net cash flows and changes therein relating to estimated proved reserves, giving very specific assumptions to be made such as the use of a 10% discount rate and an unweighted average of commodity prices in the prior 12-month period using the closing prices on the first day of each month as well as current costs applicable at the date of the estimate. These and other required assumptions have not always proved accurate in the past, and other valid assumptions would give rise to substantially different results. In addition, the 10% discount rate required to be used is not necessarily the most appropriate discount factor based on our cost of capital and the risks associated with our business and the oil and natural gas industry in general. This information is not the fair value nor does it represent the expected present value of future cash flows of our crude oil and condensate, natural gas liquid, and natural gas and synthetic crude oil reserves.
(In millions)U.S. Canada E.G. 
Other
Africa
 Other Int'l TotalU.S. E.G. Libya Other Int'l Total
Year Ended December 31, 2017         
Future cash inflows$36,480
 $1,966
 $10,303
 $1,403
 $50,152
Future production and support costs(14,796) (748) (931) (821) (17,296)
Future development costs(6,987) (7) (501) (1,247) (8,742)
Future income tax expenses(786) (274) (8,387) 496
 (8,951)
Future net cash flows$13,911
 $937
 $484
 $(169)
(a) 
$15,163
10% annual discount for timing of cash flows(7,009) (235) (224) 168
 (7,300)
Standardized measure of discounted future net cash flows-
related to continuing operations
$6,902
 $702
 $260
 $(1) $7,863
Standardized measure of discounted future net cash flows-
related to discontinued operations
      

 
Year Ended December 31, 2016                    
Future cash inflows$27,610
 $26,803
 $1,977
 $8,511
 $921
 $65,822
$27,610
 $1,977
 $8,511
 $921
 $39,019
Future production and support costs(12,758) (20,208) (824) (930) (673) (35,393)(12,758) (824) (930) (673) (15,185)
Future development costs(7,233) (3,209) (13) (296) (1,345) (12,096)(7,233) (13) (296) (1,345) (8,887)
Future income tax expenses
 (446) (251) (6,884) 514
 (7,067)
 (251) (6,884) 514
 (6,621)
Future net cash flows$7,619
 $2,940
 $889
 $401
 $(583)
(a) 
$11,266
$7,619
 $889
 $401
 $(583)
(a) 
$8,326
10% annual discount for timing of cash flows(4,355) (1,864) (264) (143) 313
 (6,313)(4,355) (264) (143) 313
 (4,449)
Standardized measure of discounted future net cash flows-
-related to continuing operations$3,264
 $1,076
 $625
 $258
 $(270) $4,953
-related to discontinued operations$
 $
 $
 $
 
 
Standardized measure of discounted future net cash flows-
related to continuing operations
$3,264
 $625
 $258
 $(270) $3,877
Standardized measure of discounted future net cash flows-
related to discontinued operations
      

 $1,076
Year Ended December 31, 2015                    
Future cash inflows$31,026
 $31,087
 $2,671
 $12,157
 $1,281
 $78,222
$31,026
 $2,671
 $12,157
 $1,281
 $47,135
Future production and support costs(12,270) (27,459) (1,095) (901) (902) (42,627)(12,270) (1,095) (901) (902) (15,168)
Future development costs(6,637) (2,929) (94) (689) (1,537) (11,886)(6,637) (94) (689) (1,537) (8,957)
Future income tax expenses(778) 
 (369) (9,857) 602
 (10,402)(778) (369) (9,857) 602
 (10,402)
Future net cash flows$11,341
 $699
 $1,113
 $710
 $(556)
(a) 
$13,307
$11,341
 $1,113
 $710
 $(556)
(a) 
$12,608
10% annual discount for timing of cash flows(6,082) (534) (380) (441) 352
 (7,085)(6,082) (380) (441) 352
 (6,551)
Standardized measure of discounted future net cash flows-
-related to continuing operations$5,259
 $165
 $733
 $269
 $(204) $6,222
-related to discontinued operations$
 $
 $
 $
 $
 $
Year Ended December 31, 2014           
Future cash inflows$66,307
 $55,675
 $5,027
 $23,803
 $3,040
 $153,852
Future production and support costs(19,504) (34,838) (1,270) (803) (1,452) (57,867)
Future development costs(14,626) (9,754) (259) (680) (1,669) (26,988)
Future income tax expenses(8,124) (2,190) (922) (21,008) (9) (32,253)
Future net cash flows$24,053
 $8,893
 $2,576
 $1,312
 $(90) $36,744
10% annual discount for timing of cash flows(12,138) (6,613) (915) (742) 221
 (20,187)
Standardized measure of discounted future net cash flows-
-related to continuing operations$11,915
 $2,280
 $1,661
 $570
 $131
 $16,557
-related to discontinued operations$
 $
 $
 $
 $
 $
Standardized measure of discounted future net cash flows-
related to continuing operations
$5,259
 $733
 $269
 $(204) $6,057
Standardized measure of discounted future net cash flows-
related to discontinued operations
      

 $165
(a) 
Future cash flows for Other International reflects the impact of future abandonment costs related to the U.K.


Supplementary Information on Oil and Gas Producing Activities (Unaudited)


Changes in the Standardized Measure of Discounted Future Net Cash Flows
Year Ended December 31,Year Ended December 31, 
(In millions)2016 2015 20142017 2016 2015 
Sales and transfers of oil and gas produced, net of production and support costs$(1,813) $(2,460) $(5,284)$(2,853) $(1,634) $(2,422) 
Net changes in prices and production and support costs related to future production(3,173)
(b) 
(25,239)
(b) 
(2,688)4,916
 (3,621)
(b) 
(21,309)
(b) 
Extensions, discoveries and improved recovery, less related costs238
 1,100
 3,539
661
 (2,174) 6
 
Development costs incurred during the period700
 1,694
 4,088
1,027
 669
 1,693
 
Changes in estimated future development costs2,492
 9,397
 (1,423)183
 2,534
 7,247
 
Revisions of previous quantity estimates(a)
(1,088) (7,625) (3,193)497
 654
 (5,682) 
Net changes in purchases and sales of minerals in place(651) (460) (168)102
 (651) (460) 
Accretion of discount1,020
 2,967
 3,132
698
 1,005
 2,719
 
Net change in income taxes1,006
 10,291
 3,312
(1,245) 1,038
 9,989
 
Net change for the year(1,269) (10,335) 1,315
3,986
 (2,180) (8,219) 
Beginning of the year related to continuing operations6,222
 16,557
 15,242
3,877
 6,057
 14,276
 
End of the year related to continuing operations$4,953
 $6,222
 $16,557
$7,863
 $3,877
 $6,057
 
Net change for the year related to discontinued operations$
 $
 $(2,530)$
 $911
 $(2,115) 
(a) 
Includes amounts resulting from changes in the timing of production.
(b)  
Decrease primarily due to lower realized prices.



Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure
None.
Item 9A. Controls and Procedures
Disclosure Controls and Procedures
An evaluation of the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934) was carried out under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer. As of the end of the period covered by this Report based upon that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that the design and operation of these disclosure controls and procedures were effective as of December 31, 2016.2017.
Management's Annual Report on Internal Control Over Financial Reporting
See "Management’s Report on Internal Control over Financial Reporting" under Item 8 of this Form 10-K.
Attestation Report of the Registered Public Accounting Firm
See "Report of Independent Registered Public Accounting Firm" under Item 8 of this Form 10-K.
Changes in Internal Control Over Financial Reporting
During the fourth quarter of 2016,2017, there were no changes in our internal control over financial reporting that have materially affected, or were reasonably likely to materially affect, our internal control over financial reporting.
Item 9B. Other Information
None.

PART III
Item 10. Directors, Executive Officers and Corporate Governance
Information required by this item is incorporated by reference to "Proposal 1: Election of Directors," "Corporate Governance—Committees of the Board" and "Section 16(a) Beneficial Ownership Reporting Compliance" in our Proxy Statement for the 20172018 Annual Meeting of Stockholders, to be filed with the SEC within 120 days of December 31, 20162017 (the "2017"2018 Proxy Statement").
See "Executive Officers of the Registrant" under Item 1 of this Form 10-K for information about our executive officers.
Our Code of Business Conduct and the Code of Ethics for Senior Financial Officers, arewhich applies to the Company’s principal executive officer, principal financial officer, principal accounting officer or controller, or persons performing similar functions, is available on our website at www.marathonoil.com.www.marathonoil.com under Investors—Corporate Governance. You may request a printed copy free of charge by sending a request to the Corporate Secretary. We intend to disclose any amendments and any waivers to our Code of Ethics for Senior Financial Officers on our website at www.marathonoil.com under Investors —Corporate Governance within four business days. The waiver information will remain on the website for at least 12 months after the initial disclosure of such waiver.

Item 11. Executive Compensation
Information required by this item is incorporated by reference to "Corporate Governance—Compensation Committee Interlocks and Insider Participation," "Compensation Committee Report," "Director Compensation," "Compensation Discussion and Analysis" and "Executive Compensation" in the 20172018 Proxy Statement.
Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters
Portions of information required by this item are incorporated by reference to "Security Ownership of Certain Beneficial Owners and Management" in the 20172018 Proxy Statement.
Securities Authorized for Issuance Under Equity Compensation Plans
The following table provides information as of December 31, 20162017 with respect to shares of Marathon Oil common stock that may be issued under our existing equity compensation plans:
Marathon Oil Corporation 2016 Incentive Compensation Plan (the "2016 Plan")
Marathon Oil Corporation 2012 Incentive Compensation Plan (the "2012 Plan") – No additional awards will be granted under this plan.
Marathon Oil Corporation 2007 Incentive Compensation Plan (the "2007 Plan") – No additional awards will be granted under this plan.
Marathon Oil Corporation 2003 Incentive Compensation Plan (the "2003 Plan") – No additional awards will be granted under this plan.
Deferred Compensation Plan for Non-Employee Directors – No additional awards will be granted under this plan.

Plan category
Number of securities to be issued upon
exercise of outstanding options, warrants and rights
 
Weighted-average
exercise price of
outstanding options,
warrants and rights(c)
 
Number of securities
remaining available for future issuance
under equity compensation plans
 
Number of securities to be issued upon
exercise of outstanding options, warrants and rights
 
Weighted-average
exercise price of
outstanding options,
warrants and rights(c)
 
Number of securities
remaining available for future issuance
under equity compensation plans
 
Equity compensation plans approved by stockholders13,566,560
(a) 
$27.31 53,818,078
(d) 
11,915,472
(a) 
$25.52 43,840,884
(d) 
Equity compensation plans not approved by stockholders12,291
(b) 
N/A 
  12,291
(b) 
N/A 
  
Total13,578,851
  N/A 53,818,078
  11,927,763
  N/A 43,840,884
  
(a) 
Includes the following:
4,214,949736,199 stock options outstanding under the 2016 Plan; 3,991,905 stock options outstanding under the 2012 Plan; 7,700,5845,591,708 stock options outstanding under the 2007 Plan;
353,503399,114 common stock units that have been credited to non-employee directors pursuant to the non-employee director deferred compensation program and the annual director stock award program established under the 2016 Plan, 2012 Plan, 2007 Plan and 2003 Plan. Common stock units credited under the 2016 Plan, 2012 Plan, 2007 Plan and 2003 Plan were 166,680, 152,82869,556, 142,724, 152,839 and 33,995, respectively;
1,297,524
1,196,546 restricted stock units granted to non-officers under the 2012 Plan and 2016 Plan and outstanding as of December 31, 2016.2017.
In addition to the awards reported above, 60,7162,850,798 and 429,7083,525,501 shares of restricted stock were issued and outstanding as of December 31, 2016, but subject to forfeiture restrictions under the 2016 Plan. In addition to the awards reported above 5,206,301 shares of restricted stock were issued and outstanding as of December 31, 2016,2017, but subject to forfeiture restrictions under the 2012 Plan.and 2016 Plans, respectively.
(b) 
Reflects awards of common stock units made to non-employee directors under the Deferred Compensation Plan for Non-Employee Directors prior to April 30, 2003. When a non-employee director leaves the Board, he or she will be issued actual shares of Marathon Oil common stock in place of the common stock units.

(c) 
The weighted-average exercise prices do not take the restricted stock units or common stock units into account as these awards have no exercise price.
(d) 
Reflects the shares available for issuance under the 2016 Plan. No more than 22,331,15218,496,714 of these shares may be issued for awards other than stock options or stock appreciation rights. In addition, shares related to grants that are forfeited, terminated, canceled or expire unexercised shall again immediately become available for issuance.
The Deferred Compensation Plan for Non-Employee Directors is our only equity compensation plan that has not been approved by our stockholders. Our authority to make equity grants under this plan was terminated effective April 30, 2003. Under the Deferred Compensation Plan for Non-Employee Directors, all non-employee directors were required to defer half of their annual retainers in the form of common stock units. On the date the retainer would have otherwise been payable to the non-employee director, we credited an unfunded bookkeeping account for each non-employee director with a number of common stock units equal to half of his or her annual retainer divided by the fair market value of our common stock on that date. The ongoing value of each common stock unit equals the market price of a share of our common stock. When the non-employee director leaves the Board, he or she is issued actual shares of our common stock equal to the number of common stock units in his or her account at that time.
Item 13. Certain Relationships and Related Transactions, and Director Independence
Information required by this item is incorporated by reference to "Transactions with Related Persons," and "Proposal 1: Election of Directors—Director Independence" in the 20172018 Proxy Statement.
Item 14. Principal Accountant Fees and Services
Information required by this item is incorporated by reference to "Proposal 2: Ratification of Independent Auditor for 2017"2018" in the 20172018 Proxy Statement.

PART IV
Item 15. Exhibits, Financial Statement Schedules
A. Documents Filed as Part of the Report
1. Financial Statements – See Part II, Item 8. of this Annual Report on Form 10-K.
2. Financial Statement Schedules – FinancialThe audited financial statements and related footnotes of Alba Plant LLC, our equity method investment, are being filed within Exhibit 99.9 in accordance with Rule 3-09 of Regulation S-X. All other financial statement schedules required under SEC rules but not included in this Annual Report on Form 10-K are omitted because they are not applicable or the required information is contained in the consolidated financial statements or notes thereto.
3. Exhibits – The information required by this Item 15 is incorporated by reference to the Exhibit Index accompanying this Annual Report on Form 10-K.
Item 16. Form 10-K Summary
None.


SIGNATURES
Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.
February 24, 201722, 2018 MARATHON OIL CORPORATION
   
  By:    /s/ GARY E. WILSON
  Gary E. Wilson
  Vice President, Controller and Chief Accounting Officer

POWER OF ATTORNEY
Each person whose signature appears below appoints Lee M. Tillman, Patrick J. Wagner,Dane E. Whitehead, and Gary E. Wilson, and each of them, as his or her true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments to this Annual Report on Form 10-K, and to file the same, with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, with full power and authority to each of said attorneys-in-fact and agents to do and perform each and every act whatsoever that is necessary, appropriate or advisable in connection with any or all of the above-described matters and to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents or any of them or their substitutes, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Exchange Act of 1934, this report has been signed below by the following persons on February 24, 201722, 2018 on behalf of the registrant and in the capacities indicated.
Signature Title
   
/S/ LEE M. TILLMAN
 President and Chief Executive Officer and Director
Lee M. Tillman  
   
/S/ PATRICK J. WAGNERDane E. Whitehead
 InterimExecutive Vice President and Chief Financial Officer and Vice President Corporate Development and Strategy
Patrick J. WagnerDane E. Whitehead 
   
/s/ GARY E. WILSON Vice President, Controller and Chief Accounting Officer
Gary E. Wilson  
   
/S/ DENNIS H. REILLEY
 Chairman of the Board
Dennis H. Reilley  
   
/s/ GAURDIE E. BANISTER, JR. Director
Gaurdie E. Banister, Jr.  
   
/S/ GREGORY H. BOYCE
 Director
Gregory H. Boyce  
   
/S/ CHADWICK C. DEATON Director
Chadwick C. Deaton  
   
/S/ MARCELA E. DONADIO
 Director
Marcela E. Donadio  
   
/S/ PHILIP LADER
 Director
Philip Lader  
   
/S/ MICHAEL E. J. PHELPS
 Director
Michael E. J. Phelps  

Exhibit Index
Exhibit  Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit DescriptionForm Exhibit Filing Date
3 Articles of Incorporation and By-laws
3.1 Restated Certificate of Incorporation of Marathon Oil Corporation10-Q 3.1 8/8/2013
3.2 Marathon Oil Corporation By-laws (Amended and restated as of February 24, 2016)8-K 3.1 3/1/2016
3.3 Specimen of Common Stock Certificate10-K 3.3 2/28/2014
4 Instruments Defining the Rights of Security Holders, Including Indentures
4.1 Indenture, dated as of February 26, 2002, between Marathon Oil Corporation and The Bank of New York Trust Company, N.A., successor in interest to JPMorgan Chase Bank as Trustee, relating to senior debt securities of Marathon Oil Corporation. Pursuant to CFR 229.601(b)(4)(iii), instruments with respect to long-term debt issues have been omitted where the amount of securities authorized under such instruments does not exceed 10% of the total consolidated assets of Marathon Oil. Marathon Oil hereby agrees to furnish a copy of any such instrument to the Securities and Exchange Commission upon its request10-K 4.2 2/28/2014
10 Material Contracts     
10.1 Amended and Restated Credit Agreement, dated as of May 28, 2014, among Marathon Oil Corporation, as borrower, The Royal Bank of Scotland plc, as syndication agent, Citibank, N.A., Morgan Stanley Senior Funding, Inc. and The Bank of Nova Scotia, as documentation agents, JPMorgan Chase Bank, N.A., as administrative agent, and certain other financial institutions named therein8-K 4.1 6/2/2014
10.2 First Amendment, dated as of May 5, 2015, to the Amended and Restated Credit Agreement dated as of May 28, 2014, by and among Marathon Oil Corporation, as borrower, JPMorgan Chase Bank, N.A., as administrative agent, and certain other financial institutions named therein10-Q 10.1 5/7/2015
10.3 Incremental Commitments Supplement, dated as of March 4, 2016, to the Amended and Restated Credit Agreement dated as of May 28, 2014, as amended by the First Amendment dated as of May 5, 2015, among Marathon Oil Corporation, as borrower, the lenders party thereto, The Royal Bank of Scotland Plc, as syndication agent, Citibank, N.A., Morgan Stanley Senior Funding, Inc. and The Bank of Nova Scotia, as documentation agents, and JPMorgan Chase Bank, N.A., as administrative agent.8-K 99.1 3/8/2016
10.4
 Marathon Oil Corporation 2016 Incentive Compensation PlanDEF 14A App. A 4/7/2016
10.5† Form of Marathon Oil Corporation 2016 Incentive Compensation Plan Restricted Stock Award Agreement for Section 16 Officers (3-year cliff vesting)8-K/A 10.1 10/6/2016
10.6†*
 Form of Marathon Oil Corporation 2016 Incentive Compensation Plan Restricted Stock Award Agreement for Section 16 Officers (3-year prorata vesting)     
10.7†* Form of Marathon Oil Corporation 2016 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Section 16 Officers     
10.8†* Form of Marathon Oil Corporation 2016 Incentive Compensation Plan Restricted Stock Unit Award Agreement for Non-Employee Directors (3-year cliff vesting)     
Exhibit   Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit Description Form Exhibit Filing Date
1 Underwriting Agreement      
1.1*       
2 Plan of Acquisition, Reorganization, Arrangement, Liquidation or Succession      
2.1  10-Q 10.1 5/5/2017
3 Articles of Incorporation and By-laws
3.1  10-Q 3.1 8/8/2013
3.2  8-K 3.1 3/1/2016
3.3  10-K 3.3 2/28/2014
4 Instruments Defining the Rights of Security Holders, Including Indentures
4.1  10-K 4.2 2/28/2014
10 Material Contracts      
10.1  8-K 4.1 6/2/2014
10.2  10-Q 10.1 5/7/2015
10.3  8-K 99.1 3/8/2016

ExhibitIncorporated by Reference (File No. 001-05153, unless otherwise indicated)
NumberExhibit DescriptionFormExhibitFiling Date
10.9†*

Form of Marathon Oil Corporation 2016 Incentive Compensation Plan Restricted Stock Unit Award Agreement for Non-Employee Canadian Directors (3-year cliff vesting)
10.10†Marathon Oil Corporation 2012 Incentive Compensation PlanDEF 14AApp. III3/8/2012
10.11†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Non-Qualified Stock Option Award Agreement8-K10.18/1/2014
10.12
Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Performance Unit Award Agreement10-Q10.15/7/2014
10.13
Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Performance Unit Award Agreement10-Q10.25/7/2014
10.14†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Initial CEO Option Grant Agreement10-Q10.111/6/2013
10.15†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan CEO Restricted Stock Agreement (3-year prorata vesting)10-Q10.211/6/2013
10.16†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan CEO Restricted Stock Award Agreement granted (3-year cliff vesting)10-Q10.311/6/2013
10.17†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Section 16 Officers (3-year prorata vesting)10-K10.52/22/2013
10.18†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Officers (3-year prorata vesting)10-K10.62/22/2013
10.19†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Restricted Stock Award Agreement for Section 16 Officers (3-year cliff vesting)10-K10.72/22/2013
10.20†Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Restricted Stock Award Agreement for Officers (3-year cliff vesting)10-K10.82/22/2013
10.21
Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Restricted Stock Award Agreement for Section 16 Officers (3-year prorata vesting)10-K10.92/22/2013
10.22
Form of Marathon Oil Corporation 2012 Incentive Compensation Plan Restricted Stock Award Agreement for Officers (3-year prorata vesting)10-K10.102/22/2013
10.23
Marathon Oil Corporation 2007 Incentive Compensation Plan10-K10.52/29/2012
10.24†Form of Marathon Oil Corporation 2007 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Officers10-K10.62/29/2012
10.25
Form of Marathon Oil Corporation 2007 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Section 16 Officers10-K10.52/28/2011
10.26†Form of Marathon Oil Corporation 2007 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Section 16 Officers10-K10.262/26/2010
10.27†Marathon Oil Corporation 2003 Incentive Compensation Plan10-K10.92/26/2010

Exhibit   Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit Description Form Exhibit Filing Date
10.4  8-K 99.1 6/23/2017
10.5  10-Q 10.2 8/3/2017
10.6
  DEF 14A App. A 4/7/2016
10.7†  8-K/A 10.1 10/6/2016
10.8†  10-K 10.6 2/24/2017
10.9†  10-K 10.7 2/24/2017
10.10†  10-K 10.8 2/24/2017
10.11†

  10-K 10.9 2/24/2017
10.12*       
10.13*       
10.14
  DEF 14A App. III 3/8/2012
10.15
  8-K 10.1 8/1/2014
10.16†  10-Q 10.1 5/7/2014
10.17
  10-Q 10.2 5/7/2014
10.18†  10-Q 10.1 11/6/2013

Exhibit  Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit DescriptionForm Exhibit Filing Date
10.28† Form of Marathon Oil Corporation 2003 Incentive Compensation Plan Nonqualified Stock Option Award Agreement for Officers10-K 10.22 2/26/2010
10.29†* Marathon Oil Corporation Deferred Compensation Plan for Non-Employee Directors (Amended and Restated as of December 20, 2016)     
10.30† Marathon Oil Company Deferred Compensation Plan Amended and Restated Effective June 30, 201110-K 10.32 2/29/2012
10.31† Marathon Oil Company Excess Benefit Plan Amended and Restated10-K 10.31 2/29/2012
10.32† Marathon Oil Corporation 2011 Officer Change in Control Severance Benefits Plan (as amended, effective November 1, 2014)10-K 10.36 3/2/2015
10.33
 Marathon Oil Corporation Policy for Repayment of Annual Cash Bonus Amounts10-K 10.10 2/28/2011
10.34
 Marathon Oil Corporation Executive Tax, Estate, and Financial Planning Program, Amended and Restated, Effective January 1, 200910-K 10.32 2/27/2009
10.35 Tax Sharing Agreement dated as of May 25, 2011 among Marathon Oil Corporation, Marathon Petroleum Corporation and MPC Investment LLC8-K 10.1 5/26/2011
10.36 Separation Agreement with John R. Sult, dated September 23, 20168-K 10.1 9/29/2016
10.37 Consulting Services Agreement with John R. Sult, dated September 23, 20168-K 10.2 9/29/2016
10.38 Separation Agreement with Lance W. Robertson, dated September 23, 20168-K 10.3 9/29/2016
12.1* Computation of Ratio of Earnings to Fixed Charges     
21.1* List of Significant Subsidiaries     
23.1* Consent of Independent Registered Public Accounting Firm     
23.2* Consent of GLJ Petroleum Consultants LTD., independent petroleum engineers and geologists     
23.3* Consent of Ryder Scott Company, L.P., independent petroleum engineers and geologists     
23.4* Consent of Netherland, Sewell & Associates, Inc., independent petroleum engineers and geologists     
31.1* Certification of President and Chief Executive Officer pursuant to Rule 13(a)-14 and 15(d)-14 under the Securities Exchange Act of 1934     
31.2* Certification of Chief Financial Officer pursuant to Rule 13(a)-14 and 15(d)-14 under the Securities Exchange Act of 1934     
32.1* Certification of President and Chief Executive Officer pursuant to 18 U.S.C. Section 1350     
32.2* Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350     
99.1 Report of GLJ Petroleum Consultants LTD., independent petroleum engineers and geologists for 201510-K 99.1 2/25/2016
Exhibit   Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit Description Form Exhibit Filing Date
10.19†  10-K 10.5 2/22/2013
10.20†  10-K 10.6 2/22/2013
10.21†  10-K 10.7 2/22/2013
10.22†  10-K 10.8 2/22/2013
10.23
  10-K 10.9 2/22/2013
10.24
  10-K 10.10 2/22/2013
10.25
  10-K 10.5 2/29/2012
10.26†  10-K 10.6 2/29/2012
10.27
  10-K 10.5 2/28/2011
10.28†  10-K 10.26 2/26/2010
10.29†  10-K 10.9 2/26/2010
10.30†  10-K 10.29 2/24/2017
10.31†  10-K 10.32 2/29/2012
10.32†  10-K 10.31 2/29/2012
10.33†*       
10.34
  10-K 10.10 2/28/2011
10.35
  10-K 10.32 2/27/2009
10.36  8-K 10.1 5/26/2011
12.1*       
21.1*       
23.1*       
23.2*       
23.3*       

Exhibit  Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit DescriptionForm Exhibit Filing Date
99.2 Report of GLJ Petroleum Consultants LTD., independent petroleum engineers and geologists for 201410-K 99.1 3/2/2015
99.3* Summary report of audits performed by Ryder Scott Company, L.P., independent petroleum engineers and geologists for 2016     
99.4* Summary report of audits performed by Ryder Scott Company, L.P., independent petroleum engineers and geologists for 2015     
99.5 Summary report of audits performed by Ryder Scott Company, L.P., independent petroleum engineers and geologists for 201410-K 99.7 2/25/2016
99.6* Summary report performed by Netherland, Sewell & Associates, Inc., independent petroleum engineers and geologists for 2015     
99.7 Summary report performed by Netherland, Sewell & Associates, Inc., independent petroleum engineers and geologists for 201410-K 99.4 2/25/2016
101.INS* XBRL Instance Document     
101.SCH* XBRL Taxonomy Extension Schema     
101.CAL* XBRL Taxonomy Extension Calculation Linkbase     
101.PRE* XBRL Taxonomy Extension Presentation Linkbase     
101.LAB* XBRL Taxonomy Extension Label Linkbase     
101.DEF* XBRL Taxonomy Extension Definition Linkbase     
* Filed herewith.
 Management contract or compensatory plan or arrangement.

Exhibit   Incorporated by Reference (File No. 001-05153, unless otherwise indicated)
Number Exhibit Description Form Exhibit Filing Date
23.4*       
23.5*       
31.1*       
31.2*       
32.1*       
32.2*       
99.1  10-K 99.1 2/25/2016
99.2*       
99.3*       
99.4*       
99.5  10-K 99.3 2/24/2017
99.6  10-K 99.4 2/24/2017
99.7*       
99.8  10-K 99.6 2/24/2017
99.9*       
101.INS* XBRL Instance Document      
101.SCH* XBRL Taxonomy Extension Schema      
101.CAL* XBRL Taxonomy Extension Calculation Linkbase      
101.PRE* XBRL Taxonomy Extension Presentation Linkbase      
101.LAB* XBRL Taxonomy Extension Label Linkbase      
101.DEF* XBRL Taxonomy Extension Definition Linkbase      
* Filed herewith.
 Management contract or compensatory plan or arrangement.

4