Eagle Rock Energy G&P S3 Shelf registration

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As filed with the Securities and Exchange Commission on March 26, 2013

Registration Statement No. 333-

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM S-3
REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

EAGLE ROCK ENERGY PARTNERS, L.P.*
EAGLE ROCK ENERGY FINANCE CORP.
(Exact name of registrant as specified in its charter)


Delaware Delaware (State or other jurisdiction of incorporation or organization)		69-0629883 26-4627240 (I.R.S. Employer Identification Number)

1415 Louisiana Street, Suite 2700
Houston, Texas 77002
(281) 408-1200
(Address, including zip code, and telephone number, including area code, of registrant's principal executive offices)

Charles C. Boettcher
1415 Louisiana Street, Suite 2700
Houston, Texas 77002
(281) 408-1200
(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:
Douglas E. McWilliams
Vinson & Elkins L.L.P.
1001 Fannin Street, Suite 2500
Houston, Texas 77002
(713) 758-2222

Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this registration statement.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act.


Large accelerated filer ý		Accelerated filer o		Non-accelerated filer o (Do not check if a smaller reporting company)		Smaller reporting company o

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Maximum Offering Price of all Securities to be Registered(3)	Amount of Registration Fee(6)




Common Units Representing Limited Partner Interests

Partnership Securities

Debt Securities(1)

Guarantees of Debt Securities(2)

Total	$500,000,000(4)(5)	$37,179(7)

(1): If any debt securities are issued at an original issue discount, then the offering price of such debt securities shall be in such amount as shall result in an aggregate initial offering price not to exceed $500,000,000, less the dollar amount of any registered securities previously issued hereunder.
(2): Pursuant to Rule 457(n), no separate fee is payable with respect to the guarantees of the debt securities being registered.
(3): The amount to be registered, proposed maximum offering price per unit, and proposed maximum aggregate offering price for each class of securities to be registered is not specified pursuant to General Instruction, II.D. of Form S-3.
(4): Estimated solely for the purpose of calculating the registration fee pursuant to Rule 457(o). In no event will the aggregate initial offering price of all securities offered from time to time pursuant to the prospectus included as a part of this Registration Statement exceed $500,000,000. To the extent applicable, the aggregate amount of common units registered is further limited to that which is permissible under Rule 415(a)(4) under the Securities Act. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder.
(5): There are being registered hereunder a presently indeterminate number of common units and debt securities.
(6): Calculated in accordance with Rule 457(o).
(7): This Registration Statement includes common units, partnership securities and debt securities with an aggregate offering price of $227,432,116, the issuance of which was previously registered pursuant to Registration Statement No. 333-163554 and which remain unsold. Pursuant to Rule 415(a)(6) of the Securities Act, the filing fee previously paid in connection with such unsold common units, partnership securities and debt securities will continue to be applied to such unsold common units, partnership securities and debt securities. As a result, a filing fee of $37,179 is being paid herewith in connection with the $272,567,884 of new common units, partnership securities and debt securities.

Pursuant to Rule 415(a)(6), the offering of the common units, partnership securities and debt securities covered by this Registration Statement that were previously covered by Registration Statement No. 333-163554 will be deemed terminated as of the date of effectiveness of this Registration Statement.

The Registrants hereby amend this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrants shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

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*ADDITIONAL SUBSIDIARY GUARANTOR REGISTRANTS

Exact Name of Additional Registrant as Specified in Its Charter(1)	State or Other Jurisdiction of Incorporation or Organization

CMA Pipeline Partnership, LLC	Texas	80-0117302
EROC Gathering Company, LP	Delaware	20-4435595
EROC Midstream Energy, L.P.	Delaware	14-1927069
EROC Production, LLC	Delaware	26-1562116
EROC Quitman Gathering Co., LP	Delaware	20-4435455
Eagle Rock Acquisition Partnership II, L.P.	Delaware	26-2830903
Eagle Rock Acquisition Partnership, L.P.	Delaware	26-1206706
Eagle Rock Desoto Pipeline, L.P.	Texas	06-1734875
Eagle Rock Energy Acquisition Co. II, Inc.	Delaware	26-2463364
Eagle Rock Energy Acquisition Co., Inc.	Delaware	20-0604564
Eagle Rock Energy G&P Holding, Inc.	Delaware	27-3137678
Eagle Rock Energy GP, L.P.	Delaware	68-0629881
Eagle Rock Energy G&P, LLC	Delaware	20-3296844
Eagle Rock Energy Services, L.P.	Texas	20-3384873
Eagle Rock Field Services, L.P.	Texas	20-3609438
Eagle Rock GOM, L.P.	Texas	80-0117311
Eagle Rock Gas Gathering and Processing, Ltd.	Texas	20-3296893
Eagle Rock Gas Services, LLC	Delaware	45-2017795
Eagle Rock Marketing, LLC	Delaware	27-3416989
Eagle Rock Midstream, L.P.	Texas	80-0117305
Eagle Rock Operating, L.P.	Texas	20-0410508
Eagle Rock Pipeline GP, LLC	Delaware	20-3804451
Eagle Rock Pipeline, L.P.	Delaware	20-3804503
Eagle Rock Upstream Development Company, Inc.	Delaware	20-1560113
Eagle Rock Upstream Development Company II, Inc.	Delaware	20-1477453
Eagle Rock Upstream Development II, L.P.	Texas	20-4005491
Escambia Asset Co. LLC	Delaware	20-4942000
Escambia Operating Co. LLC	Delaware	20-4943869
Galveston Bay Gathering, LLC	Texas	20-4591290
Hesco Gathering Company, LLC	Texas	74-2875152
Hesco Pipeline Company, L.L.C.	Texas	57-1219129
Midstream Gas Services, L.P.	Texas	33-1103950
Superior Gas Compression, LLC	Texas	87-0802353
Eagle Rock Mid-Continent Holding, LLC	Delaware	56-2590189
Eagle Rock Mid-Continent Operating, LLC	Delaware	56-2590204
Eagle Rock Mid-Continent Asset, LLC	Delaware	56-2590199

(1): The address for each of the Registrant Guarantors is 1415 Louisiana Street, Suite 2700, Houston, Texas 77002, and the telephone number for each of the Registrant Guarantors is (281) 408-1200.

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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED MARCH 26, 2013.

PRELIMINARY PROSPECTUS

Eagle Rock Energy Partners, L.P.
Eagle Rock Energy Finance Corp.

Common Units
Partnership Securities
Debt Securities

We may offer, from time to time, in one or more series:

•: common units representing limited partnership interests in Eagle Rock Energy Partners, L.P.;
•: partnership securities; and
•: debt securities.

Eagle Rock Energy Finance Corp. may act as co-issuer of the debt securities, and some or all other direct or indirect subsidiaries of Eagle Rock Energy Partners, L.P. may guarantee the debt securities.

The securities we may offer:

•: will have a maximum aggregate offering price of $500,000,000;
•: will be offered at prices and on terms to be set forth in one or more accompanying prospectus supplements; and
•: may be offered separately or together, or in separate series.

Our common units are traded on the Nasdaq Global Select Market under the symbol "EROC." We will provide information in the prospectus supplement for the trading market, if any, for any partnership securities and debt securities we may offer.

This prospectus provides you with a general description of the securities we may offer. Each time we offer to sell securities we will provide a prospectus supplement that will contain specific information about those securities and the terms of that offering. The prospectus supplement also may add, update or change information contained in this prospectus. This prospectus may be used to offer and sell securities only if accompanied by a prospectus supplement. You should read this prospectus and any prospectus supplement carefully before you invest. You should also read the documents we refer to in the "Where You Can Find More Information" section of this prospectus for information on us and our financial statements.

Limited partnerships are inherently different than corporations. You should carefully consider each of the factors described under "Risk Factors" beginning on page 2 of this prospectus before you make an investment in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is , 2013

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GUIDE TO READING THIS PROSPECTUS			ii
WHERE YOU CAN FIND MORE INFORMATION			ii
FORWARD-LOOKING STATEMENTS			iii
ABOUT EAGLE ROCK ENERGY PARTNERS, L.P.			1
RISK FACTORS			2
USE OF PROCEEDS			3
RATIO OF EARNINGS TO FIXED CHARGES			4
OUR CASH DISTRIBUTION POLICY			5
THE PARTNERSHIP AGREEMENT			8
DESCRIPTION OF PARTNERSHIP SECURITIES			21
DESCRIPTION OF THE COMMON UNITS			23
DESCRIPTION OF DEBT SECURITIES			25
MATERIAL TAX CONSEQUENCES			33
INVESTMENT IN EAGLE ROCK ENERGY PARTNERS, L.P. BY EMPLOYEE BENEFIT PLANS			50
PLAN OF DISTRIBUTION			53
LEGAL MATTERS			55
EXPERTS			55

You should rely only on the information contained or incorporated by reference in this prospectus. We have not authorized any other person to provide you with different information. You should not assume that the information provided in this prospectus is accurate as of any date other than the date on the front of this prospectus or that any information we have incorporated by reference herein is accurate as of any date other than the date of the document incorporated by reference.

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GUIDE TO READING THIS PROSPECTUS

This prospectus is part of a registration statement on Form S-3 that we filed with the Securities and Exchange Commission ("SEC") utilizing a "shelf" registration process or continuous offering process. Under this shelf registration process, we may, from time to time, sell up to $500,000,000 of the securities described in this prospectus in one or more offerings. Each time we offer securities, we will provide you with this prospectus and a prospectus supplement that will describe, among other things, the specific amounts and prices of the securities being offered and the terms of the offering, including, in the case of partnership securities and debt securities, the specific terms of the securities.

That prospectus supplement may include additional risk factors or other special considerations applicable to those securities and may also add, update, or change information in this prospectus. If there is any inconsistency between the information in this prospectus and any prospectus supplement, you should rely on the information in that prospectus supplement.

The following information should help you understand some of the conventions used in this prospectus.

•: Throughout this prospectus, when we use the terms "we," "us," or "Eagle Rock Energy Partners, L.P.," we are referring either to Eagle Rock Energy Partners, L.P., the registrant itself, or to Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., and our operating subsidiaries collectively, as the context requires.
•: We are managed by Eagle Rock Energy G&P, LLC, which is the general partner of our general partner, Eagle Rock Energy GP, L.P. We refer to Eagle Rock Energy G&P, LLC as "G&P" or "the general partner of our general partner." In addition, certain references to our general partner refer to Eagle Rock Energy GP, L.P. and Eagle Rock Energy G&P, LLC, collectively. Any reference to our "board of directors" refers to the board of directors of G&P. Both G&P and our general partner are wholly-owned subsidiaries of the Partnership. References herein to the officers or directors of our general partner refer to the officers and directors of G&P.
•: Throughout this prospectus, references to "Natural Gas Partners" or "NGP" refer to Natural Gas Partners VII, L.P. and Natural Gas Partners VIII, L.P. in the context of any description of our investors, and in other contexts refer to NGP Energy Capital Management, which manages a series of energy investment funds, including Natural Gas Partners VII, L.P. and Natural Gas Partners VIII, L.P. References to the "NGP Parties" refer to Natural Gas Partners, Montierra Minerals & Production, L.P., Montierra Management LLC, and each of their respective Affiliates; provided, that none of the general partner, the general partner of our general partner, the Partnership nor the Partnership's subsidiaries shall be included in the definition of "NGP Parties."

WHERE YOU CAN FIND MORE INFORMATION

We "incorporate by reference" information into this prospectus, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except for any information superseded by information contained expressly in this prospectus or any prospectus supplement, and the information we file later with the SEC will automatically supersede this information. You should not assume that the information in this prospectus is current as of any date other than the date on the front page of this prospectus.

We incorporate by reference the documents listed below and any future filings we make with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (excluding any information furnished pursuant to Items 2.02 or 7.01 on any Current Report on Form 8-K), including all such documents we may file with the SEC after the date of the initial

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registration statement and prior to the effectiveness of the registration statement, until all offerings under this registration statement are completed:

•: Our Annual Report on Form 10-K for the year ended December 31, 2012;
•: Our Current Reports on Forms 8-K (excluding Items 2.02 and 7.01 and related exhibits) filed on January 28, 2013, February 11, 2013, February 19, 2013 and March 18, 2013; and
•: The description of our common units contained in our Registration Statement on Form 8-A/A, filed on September 12, 2006 and amended on May 27, 2010, and any subsequent amendment or report filed for the purpose of updating such description.

You may request a copy of any document incorporated by reference in this prospectus and any exhibit specifically incorporated by reference in those documents, at no cost, by writing or telephoning us at the following address or phone number:

Eagle Rock Energy Partners, L.P.
Investor Relations
1415 Louisiana Street, Suite 2700
Houston, Texas 77002
(281) 408-1200

Additionally, you may read and copy any documents filed by us at the SEC's public reference room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference room. Our filings with the SEC are also available to the public from commercial document retrieval services and at the SEC's web site atwww.sec.gov.

We also make available free of charge on our website atwww.eaglerockenergy.com our Annual Reports on Form 10-K, our Quarterly Reports on Form 10-Q and our Current Reports on Form 8-K, and any amendments to those reports, as soon as reasonably practicable after we electronically file such material with the SEC. Information contained on our website is not incorporated by reference into this prospectus and you should not consider information contained on our website as part of this prospectus.

FORWARD-LOOKING STATEMENTS

This prospectus includes "forward-looking statements" as defined by the SEC. All statements, other than statements of historical facts, included in this prospectus that address activities, events or developments that we expect, believe or anticipate will or may occur in the future are forward-looking statements. These statements are based on certain assumptions made by us based on our experience and perception of historical trends, current conditions, expected future developments and other factors we believe are appropriate under the circumstances. Such statements are subject to a number of assumptions, risks and uncertainties, many of which are beyond our control, which may cause our actual results to differ materially from those implied or expressed by the forward-looking statements. We do not assume any obligation to update such forward-looking statements following the date of this prospectus. For a complete description of these risks, see our risk factors set forth in this prospectus and in our Annual Report on Form 10-K for the year ended December 31, 2012, or included in any Annual or Quarterly Report on Form 10-K or Form 10-Q filed after the date of this prospectus, which are incorporated into this prospectus. These factors include but are not limited to:

•: Drilling and geological / exploration risks;
•: Assumptions regarding oil and natural gas reserve levels and costs to exploit and timing of development;
•: Volatility or declines (including sustained declines) in commodity prices;

iii

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•: Our significant existing indebtedness;
•: Hedging activities;
•: Ability to obtain credit and access capital markets;
•: Ability to remain in compliance with the covenants set forth in our revolving credit facility and the indenture governing our senior notes;
•: Conditions in the securities and/or capital markets;
•: Future processing volumes and throughput;
•: Loss of significant customers;
•: Availability and cost of processing and transportation of natural gas liquids ("NGLs");
•: Competition in the oil and natural gas industry;
•: Relevant legislative or regulatory changes, including retroactive royalty or production tax regimes, changes in environmental, health and safety regulation, hydraulic fracturing regulation, environmental risks and liability under federal, state and foreign environmental laws and regulations;
•: Ability to make favorable acquisitions and integrate operations from such acquisitions;
•: Shortages of personnel and equipment;
•: Potential losses associated with trading in derivative contracts;
•: Increases in interest rates;
•: Creditworthiness of our counterparties;
•: Weather, including the occurrence of any adverse weather conditions and/or natural disasters affecting our business;
•: Any other factors that impact or could impact the exploration of oil or natural gas resources, including but not limited to the geology of a resource, the total amount and costs to develop recoverable reserves, legal title, regulatory, natural gas administration, marketing and operations factors relating to the extraction of oil and natural gas; and
•: Tax risk associated with pass-through investment, including potential reduction in tax shield or creation of phantom income in the event distributions are not enough to support the tax burden.

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ABOUT EAGLE ROCK ENERGY PARTNERS, L.P.

Overview

We are a domestically-focused, growth-oriented limited partnership engaged in the business of (i) gathering, compressing, treating, processing and transporting natural gas; fractionating and transporting NGLs; crude oil and condensate logistics and marketing; and natural gas marketing and trading, which collectively we call our "Midstream Business"; and (ii) developing and producing interests in oil and natural gas properties, which we call our "Upstream Business."

Relationship to Natural Gas Partners

Founded in 1988, Natural Gas Partners manages a $10.8 billion family of investment funds organized to make direct equity investments in private energy enterprises. Natural Gas Partners owns a significant equity position in us. Natural Gas Partners historically has provided us with increased exposure to acquisition opportunities. We expect that our relationship with Natural Gas Partners may continue to provide us with several significant benefits, including on-going exposure to acquisition opportunities and access to a significant group of transactional and financial professionals with a successful track record of investing in energy assets. We have agreements with Natural Gas Partners that restrict its control of our board of directors, restrict its voting rights with respect to our common units and grant certain registration rights with respect to certain of its Partnership common units.

Management of Eagle Rock Energy Partners, L.P.

Eagle Rock Energy GP, L.P., our general partner, has sole responsibility for conducting our business and for managing our operations. Because our general partner is a limited partnership, its general partner, Eagle Rock Energy G&P, LLC, conducts our business and operations, and the board of directors and executive officers of Eagle Rock Energy G&P, LLC make decisions on our behalf. Both our general partner and its general partner are our wholly-owned subsidiaries. Neither our general partner nor any of its affiliates receive any management fee or other compensation in connection with the management of our business, but they are entitled to reimbursement for all direct and indirect expenses they incur on our behalf.

As is common with publicly traded limited partnerships and in order to maximize operational flexibility, we conduct our operations through subsidiaries.

Principal Executive Offices and Internet Address

Our principal executive offices are located at 1415 Louisiana Street, Suite 2700, Houston, TX 77002 and our telephone number is (281) 408-1200. Our website is located atwww.eaglerockenergy.com. We make our periodic reports and other information filed with or furnished to the SEC, available, free of charge, through our website, as soon as reasonably practicable after those reports and other information are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference into this prospectus and does not constitute a part of this prospectus.

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RISK FACTORS

An investment in our securities involves a high degree of risk. Before you invest in our securities, you should carefully consider those risks described in our Annual Report on Form 10-K for the year ended December 31, 2012, or included in any Annual, Quarterly or Current Report on Form 10-K, Form 10-Q or Form 8-K filed after the date of this prospectus, together with all of the other information included in this prospectus and any prospectus supplement, including risks relating to our business, risks inherent in an investment in us and tax risks. If any such risks were actually to occur, our business, financial condition or results of operations could be materially adversely affected. In that case, the trading price of our common units or partnership securities, or the value of our debt securities could decline, and you could lose all or part of your investment.

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USE OF PROCEEDS

Unless otherwise indicated to the contrary in an accompanying prospectus supplement, we will use the net proceeds from the sale of the securities covered by this prospectus for general partnership purposes, which may include debt repayment, future acquisitions, capital expenditures and additions to working capital. Pending any specific application, we may initially invest net proceeds in short-term marketable securities or apply them to repayments of outstanding indebtedness.

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RATIO OF EARNINGS TO FIXED CHARGES

The table below sets forth our ratio of earnings to fixed charges for the periods indicated on a consolidated historical basis. For purposes of computing the ratios of earnings to fixed charges, earnings consist of income (loss) from continuing operations before adjustment for equity income from equity method investees plus fixed charges, amortization of capitalized interest and distributed income from investees, and our share of pretax losses of investees for which charges arising from guarantees are included in fixed charges, each as accounted for under the equity method, less capitalized interest, preference security dividend requirements of consolidated subsidiaries, and the non-controlling interest in pre-tax income of subsidiaries that have not incurred fixed charges. Fixed charges consist of the sum of interest expensed and capitalized, plus amortized premiums, discounts and capitalized expenses related to indebtedness, an estimated interest component of rental expense, and preference security dividend requirements of consolidated subsidiaries.

	Eagle Rock Energy Partners, L.P.

	Year Ended December 31,
	2008		2009			2010			2011		2012
Ratio of earnings to fixed charges		2.17x		—(a	)		—(a	)		2.41		—(a	)

(a): Earnings were inadequate to cover fixed charges by $179.8 million, $25.4 million and $153.3 million for the years ended December 31, 2009, 2010 and 2012, respectively.

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OUR CASH DISTRIBUTION POLICY

You should read the following discussion of our cash distribution policy in conjunction with the specific assumptions included in this section or in the information incorporated into this prospectus. In addition, you should read "Forward-Looking Statements" on page iii and "Risk Factors" starting on page 2 for information regarding statements that do not relate strictly to historical or current facts and certain risks inherent in our business.

For additional information regarding our operating results, you should refer to our financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2012, or included in any Annual or Quarterly Reports on Form 10-K or Form 10-Q filed after the date of this prospectus, which are incorporated into this prospectus.

Distributions of Available Cash

General. Subject to applicable law, within 45 days after the end of each quarter, we will distribute all of our available cash to our common unitholders of record on the applicable record date on a pro rata basis.

Available cash (which is defined in our Amended and Restated Partnership Agreement (as amended, the "Partnership Agreement")) means, for any fiscal quarter, (a) all cash on hand at the end of that quarter, plus if our general partner so determines, all or a portion of cash on hand on the date of determination of available cash for that quarter less (b) the amount of cash reserves established by our general partner to provide for the proper conduct of our business, including for future capital expenditures and credit and other needs, comply with applicable law, any of our debt instruments or other agreements or provide funds for distributions to our unitholders for any one or more of the next four quarters. The definition of available cash permits us to borrow cash to make distributions in times when we do not have sufficient cash on hand and to reserve cash for, among other things, the proper conduct of our business instead of distributing all of such cash.

In making decisions regarding the establishment of cash reserves, our board of directors may take into account, among other things, our projected capital requirements, its view of future commodity prices, economic conditions present and forecasted in the United States and other economies around the world, and other variables that it believes could impact the near- and long-term sustainability of our distribution level. In order to reduce the volatility in our distributions, the board of directors may decide to make distributions, even in quarters in which we do not generate sufficient distributable cash flow to fund such distributions, by using borrowings from our revolving credit facility. We plan to continue with our strategy of utilizing derivatives to mitigate the impact of changes in commodity prices on our financial results.

The board of directors will evaluate our distribution policy from time to time as conditions warrant in the future.

Rationale for Our Cash Distribution Policy. Our cash distribution policy reflects a basic judgment that, generally, our common unitholders will be better served by us distributing our cash available after expenses and reserves rather than retaining it. Because we are not subject to an entity-level federal income tax, we have more cash to distribute to you than would be the case were we subject to such tax.

Limitations on Cash Distributions and Our Ability to Change Our Cash Distribution Policy. There is no guarantee that unitholders will receive quarterly distributions from us. Our cash distribution policy may be changed at any time and is subject to certain restrictions, including the following:

•: Restrictions contained in our revolving credit facility limit our ability to make distributions. Specifically, our revolving credit facility contains material financial tests and covenants that we must satisfy. Our Annual Report on Form 10-K for the year ended December 31, 2012, which is

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incorporated by reference in this prospectus, contains a description of our revolving credit facility. Should we be unable to satisfy these restrictions or if we are otherwise in default under our revolving credit facility, we would be prohibited from making cash distributions to our common unitholders notwithstanding our stated cash distribution policy.

•: The amount of distributions we pay under our cash distribution policy and the decision to make any distribution is determined by our general partner, taking into consideration the terms of the Partnership Agreement.
•: Under Section 17-607 of the Delaware Act, we may not make a distribution to you if the distribution would cause our liabilities to exceed the fair value of our assets.
•: We may lack sufficient cash to pay distributions to our unitholders due to increases in our general and administrative expense, principal and interest payments on our outstanding debt, tax expenses including the entity-level taxation in the State of Texas, working capital requirements and anticipated cash needs.

Our Ability to Grow is Dependent on Our Ability to Access External Expansion Capital. Our intention is to distribute all of our available cash to our unitholders. As a result, we expect that we will rely primarily upon external financing sources, including commercial bank borrowings and the issuance of debt and equity securities, to fund our acquisitions and expansion capital expenditures. To the extent we are unable to finance growth externally, our cash distribution policy will significantly impair our ability to grow. In addition, because we distribute all of our available cash, our growth may not be as fast as businesses that reinvest their available cash to expand ongoing operations. To the extent we issue additional units in connection with any acquisitions or expansion capital expenditures, the payment of distributions on those additional units may increase the risk that we will be unable to maintain or increase our per unit distribution level. There are no limitations in the Partnership Agreement, revolving credit facility or the indenture governing our senior notes on our ability to issue additional units, including units ranking senior to the common units. The incurrence of additional commercial borrowings or other debt to finance our growth strategy would result in increased interest expense, which in turn may impact the available cash that we have to distribute to our unitholders.

Our distribution policy is consistent with the terms of our Partnership Agreement, which requires that we distribute all of our available cash quarterly. Our general partner has the authority to determine the amount of our available cash for any quarter. Our Partnership Agreement provides that certain determinations made by our general partner in its capacity as our general partner, including determinations of available cash and expenses and the establishment of reserves, must be made in good faith and that such determination will not be subject to any other standard imposed by our Partnership Agreement, the Delaware limited partnership statute or any other law, rule or regulation or principles of equity. Our Partnership Agreement provides that, in order for a determination by our general partner to be made in "good faith," our general partner must believe that the determination is in our best interests. Please read "Provisions of Our Partnership Agreement Relating to Cash Distributions."

The provisions of our Partnership Agreement relating to our cash distribution policy may not be modified or repealed without amending our Partnership Agreement; however, the actual amount of our cash distributions for any quarter is subject to fluctuations based on the amount of cash we generate from our business and the amount of reserves our general partner establishes in accordance with our Partnership Agreement as described above.

We will pay our distributions on or about the 15th of each February, May, August and November to holders of record on or about the 7th of each such month. If the distribution date does not fall on a business day, we will make the distribution on the business day immediately preceding the indicated distribution date.

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Distributions of Cash Upon Liquidation

If we dissolve in accordance with the Partnership Agreement, we will sell or otherwise dispose of our assets in a process called liquidation. We will first apply the proceeds of liquidation to the payment of our creditors. We will distribute any remaining proceeds to our unitholders, in accordance with their capital account balances, as adjusted to reflect any gain or loss upon the sale or other disposition of its assets in liquidation.

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THE PARTNERSHIP AGREEMENT

The following is a summary of the material provisions of our Partnership Agreement. Our Partnership Agreement is filed as Exhibit 3.1 on our current report on Form 8-K filed with the SEC on May 25, 2010. We will provide prospective investors with a copy of our Partnership Agreement upon request at no charge.

We summarize the following provisions of our Partnership Agreement elsewhere in this prospectus:

•: with regard to distributions of available cash, please read "Our Cash Distribution Policy;"
•: with regard to the transfer of common units, please read "Description of the Common Units—Transfer of Common Units;" and
•: with regard to allocations of taxable income and taxable loss, please read "Material Tax Consequences."

Organization and Duration

Our partnership was organized in May 2006 and will have a perpetual existence.

Purpose

Our purpose under the Partnership Agreement is limited to any business activity that is approved by our general partner and that lawfully may be conducted by a limited partnership organized under Delaware law; provided, that our general partner shall not cause us to engage, directly or indirectly, in any business activity that the general partner determines would cause us to be treated as an association taxable as a corporation or otherwise taxable as an entity for federal income tax purposes.

Although our general partner has the ability to cause us and our subsidiaries to engage in activities other than the business of acquiring, drilling and producing crude oil, condensate and natural gas; the business of gathering, compressing, treating, processing, transporting and selling natural gas and the business of transporting and selling NGLs, our general partner has no current plans to do so and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interests of us or the limited partners. Our general partner is authorized in general to perform all acts it determines to be necessary or appropriate to carry out our purposes and to conduct our business.

Power of Attorney

Each limited partner, and each person who acquires a unit from a unitholder, by accepting the common unit, automatically grants to our general partner and, if appointed, a liquidator, a power of attorney to, among other things, execute and file documents required for our qualification, continuance or dissolution. The power of attorney also grants our general partner the authority to amend, and to make consents and waivers under, our Partnership Agreement.

Cash Distributions

Our Partnership Agreement specifies the manner in which we will make cash distributions to holders of our common units and other partnership securities. For a description of these cash distribution provisions, please read "Our Cash Distribution Policy."

Capital Contributions

Unitholders are not obligated to make additional capital contributions, except as described below under "—Limited Liability."

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Voting Rights

The following is a summary of the unitholder vote required for the matters specified below. Matters requiring the approval of a "unit majority" require the approval of a majority of the common units outstanding.



Issuance of additional units		No approval right.
Amendment of the Partnership Agreement		Certain amendments may be made by the general partner without the approval of the unitholders. Other amendments generally require the approval of a unit majority. Please read "—Amendment of the Partnership Agreement."
Merger of our partnership or the sale of all or substantially all of our assets		Unit majority in certain circumstances. Please read "—Merger, Consolidation, Conversion, Sale or Other Disposition of Assets."
Dissolution of our partnership		Unit majority. Please read "—Termination and Dissolution."
Continuation of our business upon dissolution		Unit majority. Please read "—Termination and Dissolution."
Withdrawal of the general partner		Our general partner may not withdraw as general partner. Please read "—Withdrawal or Removal of the General Partner."
Removal of the general partner		100% of the outstanding units, including those held by our general partner and its affiliates. Please read "—Withdrawal or Removal of the General Partner."
Transfer of general partner authority		Our general partner may not transfer any or otherwise delegate the power and authority to manage and control our business and affairs. See "—Transfer or Delegation of General Partner Authority."
Transfer of ownership interests in our general partner		Our general partner must remain a direct or indirect subsidiary of ours. Please read "—Transfer of Ownership Interests in the General Partner."
Board of directors		Plurality of votes cast. See "—Board of Directors."

Limited Liability

Assuming that a limited partner does not participate in the control of our business within the meaning of the Delaware Act and that he otherwise acts in conformity with the provisions of the Partnership Agreement, his liability under the Delaware Act will be limited, subject to possible exceptions, to the amount of capital he is obligated to contribute to us for his common units plus his share of any undistributed profits and assets. If it were determined, however, that the right, or exercise of the right, by the limited partners as a group:

•: to remove or replace the general partner;

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•: to elect directors standing for election;
•: to approve some amendments to the Partnership Agreement; or
•: to take other action under the Partnership Agreement;

constituted "participation in the control" of our business for the purposes of the Delaware Act, then the limited partners could be held personally liable for our obligations under the laws of Delaware, to the same extent as the general partner. This liability would extend to persons who transact business with us who reasonably believe that the limited partner is a general partner.

Under the Delaware Act, a limited partnership may not make a distribution to a partner if, after the distribution, all liabilities of the limited partnership, other than liabilities to partners on account of their partnership interests and liabilities for which the recourse of creditors is limited to specific property of the partnership, would exceed the fair value of the assets of the limited partnership. For the purpose of determining the fair value of the assets of a limited partnership, the Delaware Act provides that the fair value of property subject to liability for which recourse of creditors is limited shall be included in the assets of the limited partnership only to the extent that the fair value of that property exceeds the nonrecourse liability. The Delaware Act provides that a limited partner who receives a distribution and knew at the time of the distribution that the distribution was in violation of the Delaware Act shall be liable to the limited partnership for the amount of the distribution for three years. Under the Delaware Act, a substituted limited partner of a limited partnership is liable for the obligations of his assignor to make contributions to the partnership, except that such person is not obligated for liabilities unknown to him at the time he became a limited partner and that could not be ascertained from the Partnership Agreement.

Our subsidiaries conduct business in eight states and we may have subsidiaries that conduct business in other states in the future. Maintenance of our limited liability as a limited partner of the operating partnership may require compliance with legal requirements in the jurisdictions in which the operating partnership conducts business, including qualifying our subsidiaries to do business there.

Limitations on the liability of limited partners for the obligations of a limited partner have not been clearly established in many jurisdictions. If, by virtue of our partnership interest in our operating partnership or otherwise, it were determined that we were conducting business in any state without compliance with the applicable limited partnership or limited liability company statute, or that the right or exercise of the right by the limited partners as a group to remove or replace the general partner, to approve some amendments to the Partnership Agreement, or to take other action under the Partnership Agreement constituted "participation in the control" of our business for purposes of the statutes of any relevant jurisdiction, then the limited partners could be held personally liable for our obligations under the law of that jurisdiction to the same extent as the general partner under the circumstances. We will operate in a manner that the general partner considers reasonable and necessary or appropriate to preserve the limited liability of the limited partners.

Fiduciary Duties

Our Partnership Agreement contains various provisions modifying and restricting the fiduciary duties that might otherwise be owed by our general partner. We have adopted these restrictions to allow affiliates to engage in transactions with us that would otherwise be prohibited by state-law fiduciary duty standards and to take into account the interests of other parties in addition to our

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interests when resolving conflicts of interest. The following is a summary of the material restrictions of the fiduciary duties owed by our general partner to the limited partners:



State-law fiduciary duty standards		Fiduciary duties are generally considered to include an obligation to act in good faith and with due care and loyalty. The duty of care, in the absence of a provision in a partnership agreement providing otherwise, would generally require a general partner to act for the partnership in the same manner as a prudent person would act on his own behalf. The duty of loyalty, in the absence of a provision in a partnership agreement providing otherwise, would generally prohibit a general partner of a Delaware limited partnership from taking any action or engaging in any transaction where a conflict of interest is present.
		The Delaware Act generally provides that a limited partner may institute legal action on behalf of the partnership to recover damages from a third party where a general partner has refused to institute the action or where an effort to cause a general partner to do so is not likely to succeed. In addition, the statutory or case law of some jurisdictions may permit a limited partner to institute legal action on behalf of himself and all other similarly situated limited partners to recover damages from a general partner for violations of its fiduciary duties to the limited partners.
Partnership agreement modified standards		Our Partnership Agreement contains provisions that waive or consent to conduct by our general partner and its affiliates that might otherwise raise issues about compliance with fiduciary duties or applicable law. For example, our Partnership Agreement provides that when our general partner is acting in its capacity as our general partner, as opposed to in its individual capacity, it must act in "good faith" and will not be subject to any other standard under applicable law. In addition, when our general partner is acting in its individual capacity, as opposed to in its capacity as our general partner, it may act without any fiduciary obligation to us or the unitholders whatsoever. These standards reduce the obligations to which our general partner would otherwise be held.
		In addition to the other more specific provisions limiting the obligations of our general partner, our Partnership Agreement further provides that our general partner and its officers and directors will not be liable for monetary damages to us, our limited partners or assignees for errors of judgment or for any acts or omissions unless there has been a final and non-appealable judgment by a court of competent jurisdiction determining that the general partner or its officers and directors acted in bad faith or engaged in fraud or willful misconduct.

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Special provisions regarding affiliated transactions		Our Partnership Agreement generally provides that affiliated transactions and resolutions of conflicts of interest not involving a vote of unitholders and that are not approved by the conflicts committee of the board of directors of our general partner must be:
		• on terms no less favorable to us than those generally being provided to or available from unrelated third parties; or
		• "fair and reasonable" to us, taking into account the totality of the relationships between the parties involved (including other transactions that may be particularly favorable or advantageous to us).
		If our general partner does not seek approval from the conflicts committee and its board of directors determines that the resolution or course of action taken with respect to the conflict of interest satisfies either of the standards set forth in the bullet points above, then it will be presumed that, in making its decision, the board of directors, which may include board members affected by the conflict of interest, acted in good faith and in any proceeding brought by or on behalf of any limited partner or the partnership, the person bringing or prosecuting such proceeding will have the burden of overcoming such presumption. These standards reduce the obligations to which our general partner would otherwise be held.

By purchasing our common units, each common unitholder automatically agrees to be bound by the provisions in the Partnership Agreement, including the provisions discussed above. This is in accordance with the policy of the Delaware Act favoring the principle of freedom of contract and the enforceability of partnership agreements. The failure of a limited partner or assignee to sign a partnership agreement does not render the Partnership Agreement unenforceable against that person.

We must indemnify our general partner and its officers, directors, managers and certain other specified persons, to the fullest extent permitted by law, against liabilities, costs and expenses incurred by our general partner or these other persons. We must provide this indemnification unless there has been a final and non-appealable judgment by a court of competent jurisdiction determining that these persons acted in bad faith or engaged in fraud or willful misconduct. We must also provide this indemnification for criminal proceedings unless our general partner or these other persons acted with knowledge that their conduct was unlawful. Thus, our general partner could be indemnified for its negligent acts if it meets the requirements set forth above. To the extent these provisions purport to include indemnification for liabilities arising under the Securities Act, in the opinion of the SEC, such indemnification is contrary to public policy and, therefore, unenforceable. Please read "—Indemnification."

In addition to the indemnification provisions in our Partnership Agreement, we have also entered into indemnification agreements with the officers and directors of G&P LLC.

Issuance of Additional Securities

Our Partnership Agreement authorizes us to issue an unlimited number of additional partnership securities for the consideration and on the terms and conditions determined by our general partner without the approval of the unitholders.

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It is possible that we will fund acquisitions through the issuance of additional common units or other partnership securities. Holders of any additional common units we issue will be entitled to share equally with the then-existing holders of common units in our distributions of available cash. In addition, the issuance of additional common units or other partnership securities may dilute the value of the interests of the then-existing holders of common units in our net assets.

In accordance with Delaware law and the provisions of our Partnership Agreement, we may also issue additional partnership securities that, as determined by our general partner, may have special voting rights to which the common units are not entitled. In addition, our Partnership Agreement does not prohibit the issuance by our subsidiaries of equity securities, which may effectively rank senior to the common units.

Our general partner has a non-economic interest in us and is not entitled to make any capital contributions or receive any distributions.

Amendment of the Partnership Agreement

General. Amendments to our Partnership Agreement may be proposed only by or with the consent of our general partner. However, our general partner will have no duty or obligation to propose any amendment and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interests of us or the limited partners. In order to adopt a proposed amendment, other than the amendments discussed below, our general partner is required to seek written approval of the holders of the number of units required to approve the amendment or call a meeting of the limited partners to consider and vote upon the proposed amendment. Except as described below, an amendment must be approved by a unit majority.

Prohibited Amendments. No amendment may be made that would:

•: enlarge the obligations of any limited partner without its consent, unless approved by at least a majority of the type or class of limited partner interests so affected; or
•: enlarge the obligations of, restrict in any way any action by or rights of, or reduce in any way the amounts distributable, reimbursable or otherwise payable by us to our general partner or any of its affiliates without the consent of our general partner, which consent may be given or withheld at its option.

The provision of our Partnership Agreement preventing the amendments having the effects described in any of the clauses above can be amended upon the approval of the holders of at least 90% of the outstanding units voting together as a single class (including units owned by our general partner and its affiliates). As of March 1, 2013, NGP beneficially owned 51,386,169 common units, representing over 35% of our outstanding common units.

No Unitholder Approval. Our general partner may generally make amendments to our Partnership Agreement without the approval of any limited partner or assignee to reflect:

•: a change in our name, the location of our principal place of business, our registered agent or our registered office;
•: the admission, substitution, withdrawal or removal of partners in accordance with our Partnership Agreement;
•: a change that our general partner determines to be necessary or appropriate to qualify or continue our qualification as a limited partnership or a partnership in which the limited partners have limited liability under the laws of any state or to ensure that neither we nor the operating

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partnership nor any of its subsidiaries will be treated as an association taxable as a corporation or otherwise taxed as an entity for federal income tax purposes;

•: an amendment that is necessary, in the opinion of our counsel, to prevent us or our general partner or its directors, officers, agents or trustees from in any manner being subjected to the provisions of the Investment Company Act of 1940, the Investment Advisors Act of 1940, or "plan asset" regulations adopted under the Employee Retirement Income Security Act of 1974, or ERISA, whether or not substantially similar to plan asset regulations currently applied or proposed;
•: an amendment that our general partner determines to be necessary or appropriate for the authorization of additional partnership securities;
•: any amendment expressly permitted in our Partnership Agreement to be made by our general partner acting alone;
•: an amendment effected, necessitated or contemplated by a merger agreement that has been approved under the terms of our Partnership Agreement;
•: any amendment that our general partner determines to be necessary or appropriate for the formation by us of, or our investment in, any corporation, partnership or other entity, as otherwise permitted by our Partnership Agreement;
•: a change in our fiscal year or taxable year and related changes;
•: conversions into, mergers with or conveyances to another limited liability entity that is newly formed and has no assets, liabilities or operations at the time of the conversion, merger or conveyance other than those it receives by way of the conversion, merger or conveyance; or
•: any other amendments substantially similar to any of the matters described in the clauses above.

In addition, our general partner may make amendments to our Partnership Agreement without the approval of any limited partner if our general partner determines that those amendments:

•: do not adversely affect the limited partners (or any particular class of limited partners) in any material respect;
•: are necessary or appropriate to satisfy any requirements, conditions or guidelines contained in any opinion, directive, order, ruling or regulation of any federal or state agency or judicial authority or contained in any federal or state statute;
•: are necessary or appropriate to facilitate the trading of limited partner interests or to comply with any rule, regulation, guideline or requirement of any securities exchange on which the limited partner interests are or will be listed for trading;
•: are necessary or appropriate for any action taken by our general partner relating to splits or combinations of units under the provisions of our Partnership Agreement; or
•: are required to effect the intent expressed in the registration statement from our initial public offering or the proxy statement for the special meeting at which our Partnership Agreement was approved or the intent of the provisions of our Partnership Agreement or are otherwise contemplated by our Partnership Agreement.

Opinion of Counsel and Unitholder Approval. Our general partner will not be required to obtain an opinion of counsel that an amendment will not result in a loss of limited liability to the limited partners or result in our being treated as an entity for federal income tax purposes in connection with any of the amendments. No other amendments to our Partnership Agreement will become effective without the approval of holders of at least 90% of the outstanding units voting as a single class unless

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we first obtain an opinion of counsel to the effect that the amendment will not affect the limited liability under applicable law of any of our limited partners.

In addition to the above restrictions, any amendment that would have a material adverse effect on the rights or preferences of any type or class of outstanding units in relation to other classes of units will require the approval of at least a majority of the type or class of units so affected. Any amendment that reduces the voting percentage required to take any action is required to be approved by the affirmative vote of limited partners whose aggregate outstanding units constitute not less than the voting requirement sought to be reduced. See "—Voting Rights."

Merger, Consolidation, Conversion, Sale or Other Disposition of Assets

A merger, consolidation or conversion of us requires the prior consent of our general partner. However, our general partner will have no duty or obligation to consent to any merger, consolidation or conversion and may decline to do so free of any fiduciary duty or obligation whatsoever to us or the limited partners, including any duty to act in good faith or in the best interest of us or the limited partners.

In addition, the Partnership Agreement generally prohibits our general partner without the prior approval of the holders of a unit majority, from causing us to, among other things, sell, exchange or otherwise dispose of all or substantially all of our assets in a single transaction or a series of related transactions, including by way of merger, consolidation or other combination, or approving on our behalf the sale, exchange or other disposition of all or substantially all of the assets of our subsidiaries. Our general partner may, however, mortgage, pledge, hypothecate or grant a security interest in all or substantially all of our assets without that approval. Our general partner may also sell all or substantially all of our assets under a foreclosure or other realization upon those encumbrances without that approval. Finally, our general partner may consummate any merger without the prior approval of our unitholders if we are the surviving entity in the transaction, our general partner has received an opinion of counsel regarding limited liability and tax matters, the transaction would not result in a material amendment to the Partnership Agreement, each of our units will be an identical unit of our partnership following the transaction, and the partnership securities to be issued do not exceed 20% of our outstanding partnership securities immediately prior to the transaction.

If the conditions specified in the Partnership Agreement are satisfied, our general partner may convert us or any of our subsidiaries into a new limited liability entity or merge us or any of our subsidiaries into, or convey all of our assets to, a newly formed entity if the sole purpose of that conversion, merger or conveyance is to effect a mere change in our legal form into another limited liability entity, our general partner has received an opinion of counsel regarding limited liability and tax matters, and the governing instruments of the new entity provide the limited partners and the general partner with the same rights and obligations as contained in the Partnership Agreement. The unitholders are not entitled to dissenters' rights of appraisal under the Partnership Agreement or applicable Delaware law in the event of a conversion, merger or consolidation, a sale of substantially all of our assets or any other similar transaction or event.

Termination and Dissolution

We will continue as a limited partnership until terminated under our Partnership Agreement. We will dissolve upon:

•: the election of our general partner to dissolve us, if approved by the holders of units representing a unit majority;
•: there being no limited partners, unless we are continued without dissolution in accordance with applicable Delaware law;

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•: the entry of a decree of judicial dissolution of our partnership; or
•: the withdrawal or removal of our general partner or any other event that results in its ceasing to be our general partner other than by reason of a transfer of its general partner interest in accordance with our Partnership Agreement or withdrawal or removal following approval and admission of a successor.

Upon a dissolution under the last clause above, the holders of a unit majority may also elect, within specific time limitations, to continue our business on the same terms and conditions described in our Partnership Agreement by appointing as a successor general partner an entity approved by the holders of units representing a unit majority, subject to our receipt of an opinion of counsel to the effect that:

•: the action would not result in the loss of limited liability of any limited partner; and
•: neither our partnership, our operating partnership nor any of our other subsidiaries would be treated as an association taxable as a corporation or otherwise be taxable as an entity for federal income tax purposes upon the exercise of that right to continue.

Liquidation and Distribution of Proceeds

Upon our dissolution, unless we are continued as a new limited partnership, the liquidator authorized to wind up our affairs will, acting with all of the powers of our general partner that are necessary or appropriate to liquidate our assets and apply the proceeds of the liquidation as described in "Our Cash Distribution Policy—Distributions of Cash Upon Liquidation." The liquidator may defer liquidation or distribution of our assets for a reasonable period of time or distribute assets to partners in kind if it determines that a sale would be impractical or would cause undue loss to our partners.

Withdrawal or Removal of the General Partner

Our general partner may not withdraw as general partner.

Our general partner may not be removed unless that removal is approved by the vote of the holders of not less than 100% of the outstanding units, voting together as a single class, including units held by our general partner and its affiliates, and we receive an opinion of counsel regarding limited liability and tax matters. Any removal of our general partner is also subject to the approval of a successor general partner by the vote of the holders of a majority of the outstanding common units voting as a separate class. As of March 1, 2013, NGP beneficially owned 51,386,169 common units, representing over 35% of our outstanding common units.

In the event of removal of a general partner under circumstances where cause exists or withdrawal of a general partner where that withdrawal violates our Partnership Agreement, a successor general partner will have the option to purchase the general partner interest of the departing general partner for a cash payment equal to the fair market value of those interests. Under all other circumstances where a general partner withdraws or is removed by the limited partners, the departing general partner will have the option to require the successor general partner to purchase the general partner interest of the departing general partner for fair market value. In each case, this fair market value will be determined by agreement between the departing general partner and the successor general partner. If no agreement is reached, an independent investment banking firm or other independent expert selected by the departing general partner and the successor general partner will determine the fair market value. Or, if the departing general partner and the successor general partner cannot agree upon an expert, then an expert chosen by agreement of the experts selected by each of them will determine the fair market value.

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If the option described above is not exercised by either the departing general partner or the successor general partner, the departing general partner's general partner interest will automatically convert into common units equal to the fair market value of those interests as determined by an investment banking firm or other independent expert selected in the manner described in the preceding paragraph.

In addition, we will be required to reimburse the departing general partner for all amounts due the departing general partner, including, without limitation, all employee-related liabilities, including severance liabilities, incurred for the termination of any employees employed by the departing general partner or its affiliates for our benefit.

Transfer or Delegation of General Partner Authority

Our general partner may not transfer any or otherwise delegate the power and authority to manage and control our business and affairs.

Transfer of Ownership Interests in the General Partner

Our general partner must remain a direct or indirect subsidiary of ours.

Transfer of Partnership Securities by the NGP Parties

Prior to May 21, 2015, the NGP Parties may not, without the prior approval of the conflicts committee of the board of directors of our general partner, sell 5% or more of the partnership securities of any class for a sales price that exceeds the market price of our common units by 5% or more except in a broadly distributed underwritten public equity offering or where such premium is shared pro rata with all unitholders.

Change of Management Provisions

Our Partnership Agreement contains specific provisions that are intended to discourage a person or group from attempting to remove our general partner or otherwise change our management. If any person or group other than our general partner and its affiliates acquires beneficial ownership of 20% or more of any class of units, that person or group loses voting rights on all of its units. This loss of voting rights does not apply to the NGP Parties, to any person or group who acquires the units with the prior approval of the board of directors of our general partner and any other person or group designated by the board of directors of our general partner.

Meetings; Voting

Except as described below regarding a person or group owning 20% or more of any class of units then outstanding, record holders of units on the record date will be entitled to notice of, and to vote at, meetings of our limited partners and to act upon matters for which approvals may be solicited.

Any action that is required or permitted to be taken by the unitholders may be taken either at a meeting of the unitholders or without a meeting if consents in writing describing the action so taken are signed by holders of the number of units necessary to authorize or take that action at a meeting. Special meetings of the unitholders may be called by our general partner or by unitholders owning at least 20% of the outstanding units of the class for which a meeting is proposed. We hold annual meetings for the election of a portion of our directors. Please read "—Board of Directors." Unitholders may vote either in person or by proxy at meetings. The holders of a majority of the outstanding units of the class or classes for which a meeting has been called represented in person or by proxy will constitute a quorum unless any action by the unitholders requires approval by holders of a greater percentage of the units, in which case the quorum will be the greater percentage.

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Each record holder of a unit has a vote according to his percentage interest in us, although additional limited partner interests having special voting rights could be issued. Please read "—Issuance of Additional Securities." However, if at any time any person or group acquires, in the aggregate, beneficial ownership of 20% or more of any class of units then outstanding, that person or group will lose voting rights on all of its units and the units may not be voted on any matter and will not be considered to be outstanding when sending notices of a meeting of unitholders, calculating required votes, determining the presence of a quorum or for other similar purposes. This restriction does not apply to the NGP Parties and certain other holders. Please read "—Change of Management Provisions." Common units held in nominee or street name account will be voted by the broker or other nominee in accordance with the instruction of the beneficial owner unless the arrangement between the beneficial owner and his nominee provides otherwise.

Any notice, demand, request, report or proxy material required or permitted to be given or made to record holders of common units under our Partnership Agreement will be delivered to the record holder by us or by the transfer agent.

Board of Directors

Our board of directors is comprised of nine directors. Of those nine directors:

•: five directors are elected by our common unitholders other than the NGP Parties (the "Elected Directors"), three of which must be independent;
•: one management director (the "Management Director"), which will be the chief executive officer of G&P LLC or his designee; and
•: three directors appointed by NGP (the "NGP Directors").

The directors are classified with respect to their term of office into three classes as equal in number as possible. No class will contain more than one NGP Director.

Each calendar year, we hold an annual meeting of our limited partners to elect a number of individuals equal to the number of Elected Directors whose terms expire at such annual meeting to hold office until the third succeeding annual meeting or until such director's earlier death, resignation or removal. The individuals to stand for election as Elected Directors must be nominated by either a majority of the Elected Directors on the board of directors or a limited partner holding at least 10% of our outstanding common units at the time of notice for nomination. In order for a limited partner to make such nomination, it must provide notice of the nomination to our general partner not earlier than 135 days or less than 120 days prior to the anniversary of the preceding year's annual meeting and comply with certain other requirements set forth in our Partnership Agreement. The Elected Directors will be elected by a plurality of the votes cast. The NGP Parties are not entitled to vote in any election of Elected Directors unless the NGP Parties' ownership interest in our outstanding common units falls below 5%. In addition, at each annual meeting, the NGP Parties will appoint a number of individuals equal to the number of NGP Directors whose terms expire at such annual meeting, to hold office until the third succeeding annual meeting or until such director's earlier death, resignation or removal.

An Elected Director may be removed only for cause upon the vote of a majority of other Elected Directors. An NGP Director may be removed at any time by Natural Gas Partners or for cause by a majority of the remaining directors. In addition, if at any time that the NGP Parties' ownership interest in our outstanding common units falls below 20% or 10%, however, Natural Gas Partners will only have the right to nominate and elect two or one NGP Directors, respectively. If the NGP Parties' ownership interest in our outstanding common units falls below 5%, then all of our directors will be elected by our common unitholders.

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Any vacancies in Elected Directors (whether due to death, resignation or removal of an Elected Director or an increase in the total number of Elected Directors) may be filled, until the next annual meeting at which the term of such class expires, by a majority of the remaining Elected Directors then in office. An Elected Director may be removed only for cause and only upon a vote of the majority of the remaining Elected Directors then in office. Any vacancies in NGP Directors may be filled by NGP in its sole discretion.

Status as Limited Partner

By transfer of common units in accordance with our Partnership Agreement, each transferee of common units shall be admitted as a limited partner with respect to the common units transferred when such transfer and admission is reflected in our books and records. Except as described under "—Limited Liability," the common units will be fully paid, and unitholders will not be required to make additional contributions.

Non-Citizen Assignees; Redemption

If we are or become subject to federal, state or local laws or regulations that, in the reasonable determination of our general partner, create a substantial risk of cancellation or forfeiture of any property that we have an interest in because of the nationality, citizenship or other related status of any limited partner, we may redeem the units held by the limited partner at their current market price. In order to avoid any cancellation or forfeiture, our general partner may require each limited partner to furnish information about his nationality, citizenship or related status. If a limited partner fails to furnish information about his nationality, citizenship or other related status within 30 days after a request for the information or our general partner determines after receipt of the information that the limited partner is not an eligible citizen, the limited partner may be treated as a non-citizen assignee. A non-citizen assignee, is entitled to an interest equivalent to that of a limited partner for the right to share in allocations and distributions from us, including liquidating distributions. A non-citizen assignee does not have the right to direct the voting of his units and may not receive distributions in-kind upon our liquidation.

Indemnification

Under our Partnership Agreement, in most circumstances, we will indemnify the following persons, to the fullest extent permitted by law, from and against all losses, claims, damages or similar events:

•: our general partner;
•: any departing general partner;
•: any person who is or was an affiliate of a general partner or any departing general partner;
•: any person who is or was a director, officer, member, partner, fiduciary or trustee of any entity set forth in the preceding three bullet points;
•: any person who is or was serving as director, officer, member, partner, fiduciary or trustee of another person at the request of our general partner or any departing general partner; and
•: any person designated by our general partner.

Any indemnification under these provisions will only be out of our assets. Unless it otherwise agrees, our general partner will not be personally liable for, or have any obligation to contribute or lend funds or assets to us to enable us to effectuate, indemnification. We may purchase insurance against liabilities asserted against and expenses incurred by persons for our activities, regardless of whether we would have the power to indemnify the person against liabilities under our Partnership Agreement.

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In addition to the indemnification provisions in our Partnership Agreement, we have also entered into indemnification agreements with the officers and directors of G&P LLC.

Reimbursement of Expenses

Our Partnership Agreement requires us to reimburse our general partner for all direct and indirect expenses it incurs or payments it makes on our behalf and all other expenses allocable to us or otherwise incurred by our general partner in connection with operating our business. These expenses include salary, bonus, incentive compensation and other amounts paid to persons who perform services for us or on our behalf and expenses allocated to our general partner by its affiliates. The general partner is entitled to determine in good faith the expenses that are allocable to us.

Books and Reports

Our general partner is required to keep appropriate books of our business at our principal offices. The books will be maintained for both tax and financial reporting purposes on an accrual basis. For tax and fiscal reporting purposes, our fiscal year is the calendar year.

We will furnish or make available to record holders of common units, within 120 days after the close of each fiscal year, an annual report containing audited financial statements and a report on those financial statements by our independent public accountants. Except for our fourth quarter, we will also furnish or make available summary financial information within 90 days after the close of each quarter.

We will furnish each record holder of a unit with information reasonably required for tax reporting purposes within 90 days after the close of each calendar year. This information is expected to be furnished in summary form so that some complex calculations normally required of partners can be avoided. Our ability to furnish this summary information to unitholders will depend on the cooperation of unitholders in supplying us with specific information. Every unitholder will receive information to assist him in determining his federal and state tax liability and filing his federal and state income tax returns, regardless of whether he supplies us with information.

Right to Inspect Our Books and Records

Our Partnership Agreement provides that a limited partner can, for a purpose reasonably related to his interest as a limited partner, upon reasonable written demand stating the purpose of such demand and at his own expense, have furnished to him:

•: a current list of the name and last known address of each partner;
•: a copy of our tax returns;
•: information as to the amount of cash, and a description and statement of the agreed value of any other property or services, contributed or to be contributed by each partner and the date on which each partner became a partner;
•: copies of our Partnership Agreement, our certificate of limited partnership, related amendments and powers of attorney under which they have been executed;
•: information regarding the status of our business and financial condition; and
•: any other information regarding our affairs as is just and reasonable.

Our general partner may, and intends to, keep confidential from the limited partners trade secrets or other information the disclosure of which our general partner believes in good faith is not in our best interests or that we are required by law or by agreements with third parties to keep confidential.

Registration Rights

Under our Partnership Agreement, we have agreed to register for resale under the Securities Act and applicable state securities laws any common units or other partnership securities proposed to be sold by our general partner or any of its affiliates (including, without limitation, the NGP Parties) or their assignees if an exemption from the registration requirements is not otherwise available. These registration rights continue for two years following any withdrawal or removal of Eagle Rock Energy GP, L.P. as general partner. We are obligated to pay all expenses incidental to the registration, excluding underwriting discounts and fees.

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DESCRIPTION OF PARTNERSHIP SECURITIES

Our Partnership Agreement authorizes us to issue an unlimited number of additional limited partner interests and other equity securities for the consideration and on the terms and conditions established by our general partner in its sole discretion without the approval of any limited partners.

It is possible that we will fund acquisitions through the issuance of additional common units or other equity securities. Holders of any additional common units we issue will be entitled to share equally with the then-existing holders of common units in our distributions of available cash. In addition, the issuance of additional partnership interests may dilute the value of the interests of the then-existing holders of common units in our net assets.

In accordance with Delaware law and the provisions of our Partnership Agreement, we also may issue additional partnership interests that, in the sole discretion of our general partner, have special voting rights to which the common units are not entitled.

Upon issuance of additional partnership interests, our general partner may make, but is not required to make, additional capital contributions in us. If our general partner chooses not to make an additional capital contribution equal to its percentage interest, such interest will be reduced to reflect its percentage of the total capital contributed.

The following is a description of the general terms and provisions of our partnership securities. The particular terms of any series of partnership securities will be described in the applicable prospectus supplement and the amendment to our Partnership Agreement, if necessary, relating to that series of partnership securities, which will be filed as an exhibit to or incorporated by reference in this prospectus at or before the time of issuance of any such series of partnership securities. If so indicated in a prospectus supplement, the terms of any such series may differ from the terms set forth below.

Our general partner is authorized to approve the issuance of one or more series of partnership securities without further authorization of the limited partners and to fix the number of securities, the designations, rights, privileges, restrictions and conditions of any such series.

The applicable prospectus supplement will set forth the number of securities, particular designation, relative rights and preferences and the limitations of any series of partnership securities in respect of which this prospectus is delivered. The particular terms of any such series will include the following:

•: the maximum number of securities to constitute the series and the designation and ranking thereof;
•: the annual distribution rate, if any, on securities of the series, whether such rate is fixed or variable or both, the dates from which distributions will begin to accrue or accumulate, whether distributions will be cumulative and whether such distributions will be paid in cash, securities or otherwise;
•: whether the securities of the series will be redeemable and, if so, the price at the terms and conditions on which the securities of the series may be redeemed, including the time during which securities of the series may be redeemed and any accumulated distributions thereof that the holders of the securities of the series will be entitled to receive upon the redemption thereof;
•: the liquidation preference, if any, applicable to securities of the series;
•: the terms and conditions, if any, on which the securities of the series will be convertible into, or exchangeable for, securities of any other class or classes of partnership securities, including the price or prices or the rate or rates of conversion or exchange and the method, is any, of adjusting the same; and

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•: the voting rights, if any, of the securities of the series.

Partnership securities will be fully paid and non-assessable when issued upon full payment of the purchase price therefor. The prospectus supplement will contain, if applicable, a description of the material United States federal income tax consequences relating to the purchase and ownership of the series of partnership securities offered by the prospectus supplement. The transfer agent, registrar and distributions disbursement agent for the partnership securities will be designated in the applicable prospectus supplement.

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DESCRIPTION OF THE COMMON UNITS

The Common Units

The common units represent limited partner interests in us. The holders of common units are entitled to participate in distributions and exercise the rights or privileges available to limited partners under our Partnership Agreement. For a description of the relative rights and preferences of holders of common units in and to distributions, please read this section and "Our Cash Distribution Policy and Restrictions on Distributions." For a description of the rights and privileges of limited partners under our Partnership Agreement, including voting rights, please read "The Partnership Agreement."

Transfer Agent and Registrar

Duties. American Stock Transfer & Trust Company serves as registrar and transfer agent for the common units. We pay all fees charged by the transfer agent for transfers of common units except the following that must be paid by unitholders:

•: surety bond premiums to replace lost or stolen certificates, taxes and other governmental charges;
•: special charges for services requested by a common unitholder; and
•: other similar fees or charges.

There is no charge to unitholders for disbursements of our cash distributions. We indemnify the transfer agent, its agents and each of their stockholders, directors, officers and employees against all claims and losses that may arise out of acts performed or omitted for its activities in that capacity, except for any liability due to any gross negligence or intentional misconduct of the indemnified person or entity.

Resignation or Removal. The transfer agent may resign, by notice to us, or be removed by us. The resignation or removal of the transfer agent will become effective upon our appointment of a successor transfer agent and registrar and its acceptance of the appointment. If no successor has been appointed and has accepted the appointment within 30 days after notice of the resignation or removal, our general partner may act as the transfer agent and registrar until a successor is appointed.

Transfer of Common Units

•: represents that the transferee has the capacity, power and authority to become bound by our Partnership Agreement;
•: automatically agrees to be bound by the terms and conditions of, and is deemed to have executed, our Partnership Agreement; and
•: gives the consents and approvals contained in our Partnership Agreement.

A transferee will become a substituted limited partner of our partnership for the transferred common units automatically upon the recording of the transfer on our books and records. Our general partner will cause any transfers to be recorded on our books and records no less frequently than quarterly.

We may, at our discretion, treat the nominee holder of a common unit as the absolute owner. In that case, the beneficial holder's rights are limited solely to those that it has against the nominee holder as a result of any agreement between the beneficial owner and the nominee holder.

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Common units are securities and are transferable according to the laws governing transfers of securities. In addition to other rights acquired upon transfer, the transferor gives the transferee the right to become a substituted limited partner in our partnership for the transferred common units.

Until a common unit has been transferred on our books, we and the transfer agent may treat the record holder of the unit as the absolute owner for all purposes, except as otherwise required by law or stock exchange regulations.

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DESCRIPTION OF DEBT SECURITIES

General

The debt securities will be:

•: our direct general obligations;
•: senior debt securities; and
•: issued under an indenture among us and an indenture trustee ("Trustee").

We may issue debt securities in one or more series.

Eagle Rock Energy Partners, L.P. may issue debt securities in one or more series, and Eagle Rock Energy Finance Corp. may be a co-issuer of one or more series of debt securities. Eagle Rock Energy Finance Corp. is wholly-owned by Eagle Rock Energy Partners, L.P., and has no material assets or any liabilities other than as a co-issuer of debt securities. Its activities are limited to co-issuing debt securities and engaging in other activities incidental thereto. When used in this section "Description of Debt Securities," the terms "we," "us," "our" and "issuers" refer jointly to Eagle Rock Energy Partners, L.P. and Eagle Rock Energy Finance Corp. if the latter is a co-issuer of the series of debt securities and otherwise only to the former, and the terms "Eagle Rock Energy Partners" and "Eagle Rock Finance" refer strictly to Eagle Rock Energy Partners, L.P. and Eagle Rock Energy Finance Corp., respectively.

If we offer debt securities, we will issue them under an indenture. A form of the indenture is filed as an exhibit to the registration statement of which this prospectus is a part. We have not restated the indenture in its entirety in this description. You should read the relevant indenture because it, and not this description, controls your rights as holders of the debt securities. Capitalized terms used in the summary have the meanings specified in the indenture.

Specific Terms of Each Series of Debt Securities in the Prospectus Supplement

A prospectus supplement and a supplemental indenture or authorizing resolutions relating to any series of debt securities being offered will include specific terms relating to the offering. These terms will include some or all of the following:

•: whether Eagle Rock Finance will be a co-issuer;
•: the guarantors of the debt securities, if any;
•: the title of the debt securities;
•: the total principal amount of the debt securities;
•: the assets, if any, that are pledged as security for the payment of the debt securities;
•: whether we will issue the debt securities in individual certificates to each holder in registered form, or in the form of temporary or permanent global securities held by a depository on behalf of holders;
•: the prices at which we will issue the debt securities;
•: the portion of the principal amount that will be payable if the maturity of the debt securities is accelerated;
•: the currency or currency unit in which the debt securities will be payable, if not U.S. dollars;
•: the dates on which the principal of the debt securities will be payable;

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•: the interest rate that the debt securities will bear and the interest payment dates for the debt securities;
•: any conversion or exchange provisions;
•: any optional redemption provisions;
•: any sinking fund or other provisions that would obligate us to repurchase or redeem the debt securities;
•: any changes to or additional events of default or covenants; and
•: any other terms of the debt securities.

We may offer and sell debt securities, including original issue discount debt securities, at a substantial discount below their principal amount. The prospectus supplement will describe special U.S. federal income tax and any other considerations applicable to those securities. In addition, the prospectus supplement may describe certain special U.S. federal income tax or other considerations applicable to any debt securities that are denominated in a currency other than U.S. dollars.

Guarantees

If specified in the prospectus supplement respecting a series of debt securities, our subsidiaries specified in the prospectus supplement will fully and unconditionally guarantee to each holder and the Trustee, on a joint and several basis, the full and prompt payment of principal of, premium, if any, and interest on the debt securities of that series when and as the same become due and payable, whether at stated maturity, upon redemption or repurchase, by declaration of acceleration or otherwise. The prospectus supplement will describe any limitation on the maximum amount of any particular guarantee and the customary conditions under which guarantees may be released.

The guarantees will be general obligations of the guarantors.

Consolidation, Merger or Asset Sale

The indenture will, in general, allow us to consolidate or merge with or into another domestic entity. It will also allow each issuer to sell, lease, transfer or otherwise dispose of all or substantially all of its assets to another domestic entity. If this happens, the remaining or acquiring entity must assume all of the issuer's responsibilities and liabilities under the indenture including the payment of all amounts due on the debt securities and performance of the issuer's covenants in the indenture.

However, the indenture will impose certain requirements with respect to any consolidation or merger with or into an entity, or any sale, lease, transfer or other disposition of all or substantially all of an issuer's assets, including:

•: the remaining or acquiring entity must be organized under the laws of the United States, any state or the District of Columbia;
•: the remaining or acquiring entity must assume the issuer's obligations under the indenture; and
•: immediately after giving effect to the transaction, no Default or Event of Default (as defined under "—Events of Default and Remedies") may exist.

The remaining or acquiring entity will be substituted for the issuer in the indenture with the same effect as if it had been an original party to the indenture, and the issuer will be relieved from any further obligations under the indenture, except in the case of a lease of all or substantially all of its assets.

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No Protection in the Event of a Change of Control

Unless otherwise set forth in the prospectus supplement, the debt securities will not contain any provisions that protect the holders of the debt securities in the event of a change of control of us or in the event of a highly leveraged transaction, whether or not such transaction results in a change of control of us.

Modification of Indenture

We may supplement or amend the indenture if the holders of a majority in aggregate principal amount of the outstanding debt securities of each series affected by the supplement or amendment consent to it. Further, the holders of a majority in aggregate principal amount of the outstanding debt securities of any series may waive past defaults under the indenture and compliance by us with our covenants with respect to the debt securities of that series only. However, without the consent of each outstanding debt security affected, no modification of the indenture or waiver may:

•: reduce the principal of or extend the fixed maturity of any debt security;
•: reduce any premium payable upon redemption or change any redemption date with respect to the redemption of the debt securities;
•: reduce the rate of or extend the time for payment of interest on any debt security;
•: waive a past Default or an Event of Default in the payment of principal of or premium, if any, or interest on the debt securities or in respect of an indenture provision that cannot be modified without the consent of each affected holder;
•: except as otherwise permitted under the indenture, release any security that may have been granted with respect to the debt securities;
•: make any debt security payable in currency other than that stated in the debt securities;
•: in the case of any subordinated debt security, make any change in the subordination provisions that adversely affects the rights of any holder under those provisions;
•: impair the right of any holder to receive any payment on its debt securities on or after the due date therefor or to institute suit for the enforcement of any such payment;
•: except as otherwise permitted in the indenture, release any guarantor from its obligations under its guarantee or the indenture or change any guarantee in any manner adverse to the holders; or
•: make any change in the preceding amendment, supplement and waiver provisions (except to increase any percentage set forth therein).

We may supplement or amend the indenture without the consent of any holders of the debt securities in certain circumstances, including:

•: to establish the form of terms of any series of debt securities;
•: to cure any ambiguity, defect or inconsistency;
•: to provide for uncertificated notes in addition to or in place of certificated notes;
•: to provide for the assumption of an issuer's obligations to holders of debt securities in the case of a merger or consolidation or disposition of all or substantially all of such issuer's assets;
•: to add or release guarantors pursuant to the terms of the indenture;
•: to make any change that does not adversely affect the rights under the indenture of any holder of debt securities;

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•: to comply with requirements of the SEC in order to effect or maintain the qualification of the Indenture under the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act");
•: to evidence or provide for the acceptance of appointment under the indenture of a successor Trustee;
•: to add any additional Events of Default (as defined below) with respect to any series of debt securities; or
•: to secure the debt securities or the guarantees.

Events of Default and Remedies

"Event of Default," when used in the indenture, will mean any of the following with respect to the debt securities of any series:

•: failure to pay when due the principal of or any premium on any debt security of that series;
•: failure to pay, within 60 days of the due date, interest on any debt security of that series;
•: failure to pay when due any sinking fund payment with respect to any debt securities of that series;
•: failure on the part of an issuer to comply with the covenant described under "—Consolidation, Merger or Asset Sale";
•: failure to perform any other covenant in the indenture that continues for 30 days after written notice is given to the issuers;
•: certain events of bankruptcy, insolvency or reorganization of an issuer or any guarantor of that series;
•: if the debt securities of that series are entitled to a guarantee, the guarantee ceases to be in full force and effect; or
•: any other Event of Default provided under the terms of the debt securities of that series.

An Event of Default for a particular series of debt securities will not necessarily constitute an Event of Default for any other series of debt securities issued under the indenture. The Trustee may withhold notice to the holders of debt securities of any default (except in the payment of principal, premium, if any, or interest) if it considers such withholding of notice to be in the best interests of the holders.

If an Event of Default for any series of debt securities occurs and continues, the Trustee or the holders of at least 25% in aggregate principal amount of the debt securities of the series may declare the entire principal of, and accrued interest on, all the debt securities of that series to be due and payable immediately. If this happens, subject to certain conditions, the holders of a majority in the aggregate principal amount of the debt securities of that series can rescind the declaration.

Other than its duties in case of a default, a Trustee is not obligated to exercise any of its rights or powers under either indenture at the request, order or direction of any holders, unless the holders offer the Trustee reasonable security or indemnity. If they provide this reasonable security or indemnification, the holders of a majority in aggregate principal amount of any series of debt securities may direct the time, method and place of conducting any proceeding or any remedy available to the Trustee, or exercising any power conferred upon the Trustee, for that series of debt securities.

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No Limit on Amount of Debt Securities

The indenture will not limit the amount of debt securities that we may issue, unless we indicate otherwise in a prospectus supplement. The indenture will allow us to issue debt securities of any series up to the aggregate principal amount that we authorize.

Registration of Notes

We will issue debt securities of a series only in registered form, without coupons.

Minimum Denominations

Unless the prospectus supplement states otherwise, the debt securities will be issued only in principal amounts of $1,000 each or integral multiples of $1,000.

No Personal Liability

None of the past, present or future partners, incorporators, managers, members, directors, officers, employees, unitholders or stockholders of either issuer, the general partner of Eagle Rock Energy Partners or any guarantor, as such, will have any liability for the obligations of the issuers or any guarantor under the indenture or the debt securities or for any claim based on such obligations or their creation. Each holder of debt securities by accepting a debt security waives and releases all such liability. The waiver and release are part of the consideration for the issuance of the debt securities. The waiver may not be effective under federal securities laws, however, and it is the view of the SEC that such a waiver is against public policy.

Payment and Transfer

The Trustee will initially act as paying agent and registrar under the indenture. The issuers may change the paying agent or registrar without prior notice to the holders of debt securities, and the issuers or any of their subsidiaries may act as paying agent or registrar.

If a holder of debt securities has given wire transfer instructions to the issuers, the issuers will make all payments on the debt securities in accordance with those instructions. All other payments on any debt securities not in a global form will be made at the corporate trust office of the Trustee, unless the issuers elect to make interest payments by check mailed to the holders at their addresses set forth in the debt security register.

The Trustee and any paying agent will repay to us upon request any funds held by them for payments on the debt securities that remain unclaimed for two years after the date upon which that payment has become due. After payment to us, holders entitled to the money must look to us for payment as general creditors.

Exchange, Registration and Transfer

Debt securities of any series will be exchangeable for other debt securities of the same series, the same total principal amount and the same terms but in different authorized denominations in accordance with the indenture. Holders may present debt securities for exchange or registration of transfer at the office of the registrar. The registrar will effect the transfer or exchange when it is satisfied with the documents of title and identity of the person making the request. We will not charge a service charge for any registration of transfer or exchange of the debt securities. We may, however, require the payment of any tax or other governmental charge payable for that registration.

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We will not be required:

•: to issue, register the transfer of, or exchange debt securities of a series either during a period of 15 days prior to the mailing of a notice of redemption of debt securities of that series; or
•: to register the transfer of or exchange any debt security called for redemption, except the unredeemed portion of any debt security we are redeeming in part.

Ranking

The debt securities will rank equally in right of payment with all of our other senior and unsubordinated debt. The debt securities will be effectively subordinated, however, to all of our secured debt to the extent of the value of the collateral for that debt. We will disclose the amount of our secured debt in the prospectus supplement.

Book Entry, Delivery and Form

The debt securities of a particular series may be issued in whole or in part in the form of one or more global certificates that will be deposited with the Trustee as custodian for The Depository Trust Company, New York, New York ("DTC"), and registered in the name of DTC's nominee, Cede & Co. This means that we will not issue certificates to each holder. Instead, one or more global debt securities will be issued to DTC, who will keep a computerized record of its participants (for example, your broker) whose clients have purchased the debt securities. The participant will then keep a record of its clients who purchased the debt securities. Unless it is exchanged in whole or in part for a certificated debt security, a global debt security may not be transferred, except that DTC, its nominees and their successors may transfer a global debt security as a whole to one another.

Beneficial interests in global debt securities will be shown on, and transfers of beneficial interests in global debt securities will be made only through, records maintained by DTC and its participants.

DTC has provided us the following information: DTC is a limited-purpose trust company organized under the New York Banking Law, a "banking organization" within the meaning of the New York Banking Law, a member of the United States Federal Reserve System, a "clearing corporation" within the meaning of the New York Uniform Commercial Code and a "clearing agency" registered under the provisions of Section 17A of the Securities Exchange Act of 1934, as amended. DTC holds securities that its participants ("Direct Participants") deposit with DTC. DTC also records the settlement among Direct Participants of securities transactions, such as transfers and pledges, in deposited securities through computerized records for Direct Participants' accounts. This eliminates the need to exchange certificates. Direct Participants include securities brokers and dealers, banks, trust companies, clearing corporations and certain other organizations.

DTC's book-entry system is also used by other organizations such as securities brokers and dealers, banks and trust companies that work through a Direct Participant. The rules that apply to DTC and its Direct Participants are on file with the SEC.

DTC is a wholly-owned subsidiary of The Depository Trust & Clearing Corporation ("DTCC"). DTCC, in turn, is owned by a number of its participants and by, among other institutions, the Financial Industry Regulatory Authority, Inc. The rules that apply to DTC and its participants are on file with the SEC.

We will wire all payments on the global debt securities to DTC's nominee. We and the Trustee will treat DTC's nominee as the owner of the global debt securities for all purposes. Accordingly, we, the Trustee and any paying agent will have no direct responsibility or liability to pay amounts due on the global debt securities to owners of beneficial interests in the global debt securities.

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It is DTC's current practice, upon receipt of any payment on the global debt securities, to credit Direct Participants' accounts on the payment date according to their respective holdings of beneficial interests in the global debt securities as shown on DTC's records. In addition, it is DTC's current practice to assign any consenting or voting rights to Direct Participants whose accounts are credited with debt securities on a record date, by using an omnibus proxy. Payments by Direct Participants to owners of beneficial interests in the global debt securities, and voting by Direct Participants, will be governed by the customary practices between the Direct Participants and owners of beneficial interests, as is the case with debt securities held for the account of customers registered in "street name." However, payments will be the responsibility of the Direct Participants and not of DTC, the Trustee or us.

Debt securities represented by a global debt security will be exchangeable for certificated debt securities with the same terms in authorized denominations only if:

•: DTC notifies us that it is unwilling or unable to continue as depositary or if DTC ceases to be a clearing agency registered under applicable law and in either event a successor depositary is not appointed by us within 90 days; or
•: following an Event of Default, DTC notifies the Trustee of its decision to require that the debt securities of a series shall no longer be represented by a global debt security.

Satisfaction and Discharge; Defeasance

The indenture will be discharged and will cease to be of further effect as to all outstanding debt securities of any series issued thereunder, when:

(a) either:

(1) all outstanding debt securities of that series that have been authenticated (except lost, stolen or destroyed debt securities that have been replaced or paid and debt securities for whose payment money has theretofore been deposited in trust and thereafter repaid to us) have been delivered to the Trustee for cancellation; or

(2) all outstanding debt securities of that series that have not been delivered to the Trustee for cancellation have become due and payable by reason of the giving of a notice of redemption or otherwise or will become due and payable at their stated maturity within one year or are to be called for redemption within one year under arrangements satisfactory to the Trustee and in any case we have irrevocably deposited with the Trustee as trust funds in trust cash sufficient, without consideration of any reinvestment of interest, to pay and discharge the entire indebtedness of such debt securities not delivered to the Trustee for cancellation, for principal, premium, if any, and accrued interest to the date of such deposit (in the case of debt securities that have been due and payable) or the stated maturity or redemption date; and

(b) we have paid or caused to be paid all other sums payable by us under the indenture.

The debt securities of a particular series will be subject to legal or covenant defeasance to the extent, and upon the terms and conditions, set forth in the prospectus supplement.

Governing Law

The indenture and all of the debt securities will be governed by the laws of the State of New York.

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The Trustee

We will enter into the indenture with a Trustee that is qualified to act under the Trust Indenture Act, and with any other Trustees chosen by us and appointed in a supplemental indenture for a particular series of debt securities. We will identify in the applicable prospectus supplement, the Trustee for each series of debt securities and will file an application with the SEC under the Trust Indenture Act to qualify the Trustee.

Resignation or Removal of Trustee

If the Trustee has or acquires a conflicting interest within the meaning of the Trust Indenture Act, the Trustee must either eliminate its conflicting interest or resign, to the extent and in the manner provided by, and subject to the provisions of, the Trust Indenture Act and the indenture. Any resignation will require the appointment of a successor Trustee in accordance with the terms and conditions of the indenture.

The Trustee may resign or be removed by us with respect to one or more series of debt securities and a successor Trustee may be appointed to act with respect to any such series. The holders of a majority in aggregate principal amount of the debt securities of any series may remove the Trustee with respect to the debt securities of such series.

Limitations on Trustee if it is Our Creditor

The indenture will contain certain limitations on the right of the Trustee, in the event that it becomes a creditor of an issuer, to obtain payment of claims in certain cases, or to realize on certain property received in respect of any such claim as security or otherwise.

Annual Trustee Report to Holders of Debt Securities

The Trustee will submit an annual report to the holders of the debt securities regarding, among other things, the Trustee's eligibility to serve as such, the priority of the Trustee's claims regarding certain advances made by it, and any action taken by the Trustee materially affecting the debt securities.

Certificates and Opinions to be Furnished to Trustee

The indenture will provide that, in addition to other certificates or opinions that may be specifically required by other provisions of the indenture, every application by us for action by the Trustee shall be accompanied by a certificate of certain of our officers and an opinion of counsel (who may be our counsel) stating that, in the opinion of the signers, all conditions precedent to such action have been complied with by us.

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MATERIAL TAX CONSEQUENCES

This section summarizes the material U.S. federal income tax consequences that may be relevant to prospective common unitholders and is based upon current provisions of the U.S. Internal Revenue Code of 1986, as amended (the "Code"), existing and proposed U.S. Treasury regulations thereunder (the "Treasury Regulations"), and current administrative rulings and court decisions, all of which are subject to change. Changes in these authorities may cause the federal income tax consequences to a prospective unitholder to vary substantially from those described below. Unless the context otherwise requires, references in this section to "we" or "us" are references Eagle Rock Energy Partners, L.P. and our subsidiaries.

Legal conclusions contained in this section, unless otherwise noted, are the opinion of Vinson & Elkins L.L.P. and are based on the accuracy of representations made by us to them for this purpose. However, this section does not address all federal income tax matters that affect us or our common unitholders and does not describe the application of the alternative minimum tax that may be applicable to certain common unitholders. Furthermore, this section focuses on common unitholders who are individual citizens or residents of the United States (for federal income tax purposes), who have the U.S. dollar as their functional currency and who hold units as capital assets (generally, property that is held for investment). This section has limited applicability to corporations, partnerships (including entities treated as partnerships for U.S. federal income tax purposes), estates, trusts, non-resident aliens or other common unitholders subject to specialized tax treatment, such as tax-exempt institutions, non- U.S. persons, individual retirement accounts ("IRAs"), employee benefit plans, real estate investment trusts ("REITs") or mutual funds.Accordingly, we encourage each common unitholder to consult his own tax advisor in analyzing the federal, state, local and non-U.S. tax consequences particular to him resulting from the ownership or disposition of common units and potential changes in applicable tax laws.

We are relying on opinions and advice of Vinson & Elkins L.L.P. with respect to the matters described herein. An opinion of counsel represents only that counsel's best legal judgment and does not bind the Internal Revenue Service (the "IRS") or a court. Accordingly, the opinions and statements made herein may not be sustained by a court if contested by the IRS. Any such contest of the matters described herein may materially and adversely impact the market for the common units and the prices at which the common units trade. In addition, the costs of any contest with the IRS will be borne indirectly by our common unitholders and our general partner because the costs will reduce our cash available for distribution. Furthermore, the tax consequences of an investment in us may be significantly modified by future legislative or administrative changes or court decisions, which may be retroactively applied.

For the reasons described below, Vinson & Elkins L.L.P. has not rendered an opinion with respect to the following federal income tax issues: (1) the treatment of a common unitholder whose common units are the subject of a securities loan (e.g., a loan to a short seller to cover a short sale of common units) (please read "—Tax Consequences of Common Unit Ownership—Treatment of Securities Loans"); (2) whether our monthly convention for allocating taxable income and losses is permitted by existing Treasury Regulations (please read "—Disposition of Common Units—Allocations Between Transferors and Transferees"); (3) whether percentage depletion will be available to a unitholder or the extent of the percentage depletion deduction available to any unitholder (please read "—Tax Treatment of Operations—Oil and Natural Gas Taxation—Depletion Deductions"); (4) whether the deduction related to U.S. production activities will be available to a unitholder or the extent of such deduction to any unitholder (please read "—Tax Treatment of Operations—Oil and Natural Gas Taxation—Deduction for U.S. Production Activities"); and (5) whether our method for taking into account Section 743 adjustments is sustainable in certain cases (please read "—Tax Consequences of Common Unit Ownership—Section 754 Election" and "—Uniformity of Common Units).

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Taxation of the Partnership

Partnership Status

We expect to be treated as a partnership for U.S. federal income tax purposes and, therefore, generally will not be liable for entity-level federal income taxes. Instead, as described below, each of our common unitholders will take into account his respective share of our items of income, gain, loss and deduction as if the common unitholder had earned such income directly, even if we make no cash distributions to the common unitholder. Distributions we make to a common unitholder generally will not give rise to income or gain taxable to such unitholder unless the amount of cash distributed to him exceeds his adjusted basis in his common units.

Section 7704 of the Code generally provides that publicly traded partnerships will be treated as corporations for federal income tax purposes. However, if 90% or more of a partnership's gross income for every taxable year it is publicly traded consists of "qualifying income," the partnership may continue to be treated as a partnership for federal income tax purposes (the "Qualifying Income Exception"). Qualifying income includes income and gains derived from the exploration, development, mining or production, processing, refining, transportation, storage, processing, and marketing of crude oil, natural gas and products thereof, as well as other types of qualifying income such as interest (other than from a financial business) and dividends. We estimate that less than 1% of our current gross income is not qualifying income; however, this estimate could change from time to time. Based upon the factual representations made by us and our general partner regarding the composition of our income and the other representations set forth below, Vinson & Elkins L.L.P. is of the opinion that we will be treated as a partnership for federal income tax purposes and each of our operating subsidiaries that are partnerships or limited liability companies will be disregarded as an entity separate from us for federal income tax purposes.

In rendering its opinion, Vinson & Elkins L.L.P. has relied on factual representations made by us and our general partner. The representations made by us and our general partner upon which Vinson & Elkins L.L.P. has relied include, without limitation:

(a) Neither we nor any of our operating subsidiaries that are partnerships or limited liability companies has elected nor will elect to be treated as a corporation for federal income tax purposes;

(b) For each taxable year of the Partnership beginning with 2006, more than 90% of our gross income has been and will be income of a character that Vinson & Elkins L.L.P. has opined is "qualifying income" within the meaning of Section 7704(d) of the Code;

(c) No material portion (i.e., less than 1 percent) of the Partnership's gross income from the sales of natural gas, natural gas liquids, oil, condensate and sulfur that is treated as qualifying income is derived from sales that could be construed as sales to an end-user (i.e. sales to a purchaser whose use of the product cannot be identified as refining, processing, reselling or marketing); and

(d) Each hedging transaction that we treat as resulting in qualifying income has been and will be appropriately identified as a hedging transaction pursuant to applicable Treasury Regulations, and has been and will be associated with oil, natural gas, or products thereof that are held or to be held by us in activities that Vinson & Elkins L.L.P. has opined or will opine result in qualifying income.

We believe that these representations are true and will be true in the future.

If we fail to meet the Qualifying Income Exception, other than a failure that is determined by the IRS to be inadvertent and that is cured within a reasonable time after discovery (in which case the IRS may also require us to make adjustments with respect to our common unitholders or pay other

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amounts), we will be treated as transferring all of our assets, subject to liabilities, to a newly formed corporation, on the first day of the year in which we fail to meet the Qualifying Income Exception, in return for stock in that corporation, and then as distributing that stock to the common unitholders in liquidation. This deemed contribution and liquidation should not result in the recognition of taxable income by common unitholders or us so long as our liabilities do not exceed the tax basis of our assets. Thereafter, we would be treated as an association taxable as a corporation for federal income tax purposes.

The present federal income tax treatment of publicly traded partnerships, including us, or an investment in our common units may be modified by administrative, legislative or judicial interpretation at any time. For example, from time to time, members of the U.S. Congress propose and consider substantive changes to the existing federal income tax laws that affect publicly traded partnerships. One such legislative proposal would eliminate the qualifying income exception upon which we rely for our treatment as a partnership for U.S. federal income tax purposes. Please read "—Taxation of the Partnership—Partnership Status." We are unable to predict whether any such changes will ultimately be enacted. However, it is possible that a change in law could affect us and may be applied retroactively. Any such changes could negatively impact the value of an investment in our units.

If we were treated as an association taxable as a corporation in any taxable year, either as a result of a failure to meet the Qualifying Income Exception or otherwise, our items of income, gain, loss and deduction would be reflected only on our tax return rather than being passed through to our common unitholders, and our net income would be taxed to us at corporate rates, which is currently a maximum of 35% and would likely pay state income tax at varying rates. Distributions would generally be taxed again as corporate dividends, and no income, gains, losses or deductions would flow through to the limited partners. Because a tax would be imposed upon us as a corporation, our cash available for distributions would be substantially reduced. Therefore, treatment of us as a corporation would result in a material reduction in the anticipated cash flow and after-tax return to the unitholders, likely causing a substantial reduction in the value of our common units.

At the state level, because of widespread state budget deficits and other reasons, several states are evaluating ways to subject partnerships to entity-level taxation through the imposition of state income, franchise and other forms of taxation. We are, for example, subject to an entity level tax on the portion of our income that is generated in Texas. Imposition of such any such tax on us by any other state will reduce the cash available for distribution.

The remainder of this discussion is based on the opinion of Vinson & Elkins L.L.P. that we will be treated as a partnership for federal income tax purposes.

Tax Consequences of Common Unit Ownership

Limited Partner Status

Common Unitholders who are admitted as limited partners of Eagle Rock Energy Partners, L.P. will be treated as partners of Eagle Rock Energy Partners, L.P. for federal income tax purposes. Also:

(a) assignees who have executed and delivered transfer applications and are awaiting admission as limited partners, and

(b) common unitholders whose common units are held in street name or by a nominee and who have the right to direct the nominee in the exercise of all substantive rights attendant to the ownership of their common units

will be treated as partners of Eagle Rock Energy Partners, L.P. for federal income tax purposes. As there is no direct or indirect controlling authority addressing the federal income tax treatment of assignees of common units who are entitled to execute and deliver transfer applications and thereby

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become entitled to direct the exercise of attendant rights, but who fail to execute and deliver transfer applications, Vinson & Elkins L.L.P.'s opinion does not extend to these persons. Furthermore, a purchaser or other transferee of common units who does not execute and deliver a transfer application may not receive some federal income tax information or reports furnished to record holders of common units unless the common units are held in a nominee or street name account and the nominee or broker has executed and delivered a transfer application for those common units.

For a discussion related to the risks of losing partner status as a result of securities loans, please read "—Treatment of Securities Loans." Unitholders who are not treated as partners of the partnership as described above are urged to consult their own tax advisors with respect to the tax consequences applicable to them under the circumstances.

The references to "unitholders" in the discussion that follows are to persons who are treated as partners in Eagle Rock Energy Partners, L.P. for federal income tax purposes.

Flow-Through of Taxable Income. Subject to the discussion below under "—Entity-Level Collections of Unitholder Taxes" with respect to payments we may be required to make on behalf of our unitholders, we will not pay any federal income tax. Rather, each common unitholder will be required to report on his federal income tax return each year his share of our income, gains, losses and deductions for our taxable year or years ending with or within his taxable year. Consequently, we may allocate income to a common unitholder even if he has not received a cash distribution.

Basis of Units. A common unitholder's tax basis in its units initially will be the amount paid for those units plus the common unitholder's share of our liabilities. That basis generally will be (i) increased by the common unitholder's share of our income and any increases in such unitholder's share of our liabilities, and (ii) decreased, but not below zero, by the amount of all distributions, the common unitholder's share of our losses, and any decreases in his share of our liabilities.

Treatment of Distributions. Distributions made by us to a common unitholder generally will not be taxable to the common unitholder, unless such distributions exceed the unitholder's tax basis in his units, in which case the unitholder generally will recognize gain taxable in the manner described below under "—Disposition of Common Units."

Any reduction in a common unitholder's share of our "liabilities" will be treated as a distribution by us of cash to that common unitholder. A decrease in a common unitholder's percentage interest in us because of our issuance of additional common units may decrease the common unitholder's share of our liabilities. For purposes of the foregoing, a common unitholder's share of our nonrecourse liabilities (liabilities for which no partner bears the economic risk of loss) generally will be based upon that common unitholder's share of the unrealized appreciation (or depreciation) in our assets, to the extent thereof, with any excess liabilities allocated based on the common unitholder's share of our profits. Please read "—Disposition of Common Units."

A non-pro rata distribution of money or property (including a deemed distribution as a result of the reduction in a common unitholder's share of our liabilities as described above) may cause a common unitholder to recognize ordinary income, if the distribution reduces the common unitholder's share of our "unrealized receivables," including depreciation recapture and substantially appreciated "inventory items," both as defined in Section 751 of the Code ("Section 751 Assets"). To the extent of such reduction, the unitholder would be deemed to receive his proportionate share of the Section 751 Assets and exchange such assets with us in return for a portion of the non-pro rata distribution. This deemed exchange generally will result in the common unitholder's recognition of ordinary income in an amount equal to the excess of (1) the non-pro rata portion of that distribution over (2) the common unitholder's tax basis (generally zero) in the Section 751 Assets deemed to be relinquished in the exchange.

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Limitations on Deductibility of Losses. A unitholder may not be entitled to deduct the full amount of loss we allocate to him because his share of our losses will be limited to the lesser of (i) the unitholder's tax basis in his common units, and (ii) in the case of a unitholder that is an individual, estate, trust or certain types of closely-held corporations, the amount for which the common unitholder is considered to be "at risk" with respect to our activities. In general, a unitholder will be at risk to the extent of his tax basis in his common units, reduced by (1) any portion of that basis attributable to the unitholder's share of our liabilities, (2) any portion of that basis representing amounts otherwise protected against loss because of a guarantee, stop loss agreement or similar arrangement and (3) any amount of money he borrows to acquire or hold his common units, if the lender of those borrowed funds owns an interest in us, is related to another unitholder or can look only to the common units for repayment. A common unitholder subject to the at risk limitation must recapture losses deducted in previous years to the extent that distributions (including distributions deemed to result from a reduction in a unitholder's share of nonrecourse liabilities) cause the unitholder's at risk amount to be less than zero at the end of any taxable year.

Losses disallowed to a common unitholder or recaptured as a result of the basis or at risk limitations will carry forward and will be allowable as a deduction in a later year to the extent that the common unitholder's tax basis or at risk amount, whichever is the limiting factor, is subsequently increased. Upon a taxable disposition of units, any gain recognized by a common unitholder can be offset by losses that were previously suspended by the at risk limitation but not losses suspended by the basis limitation. Any loss previously suspended by the at risk limitation in excess of that gain can no longer be used, and will not be available to offset a common unitholder's salary or active business income.

In addition to the basis and at risk limitations, a passive activity loss limitation generally limits the deductibility of losses incurred by individuals, estates, trusts, some closely held corporations and personal service corporations from "passive activities" (generally, trade or business activities in which the taxpayer does not materially participate). The passive loss limitations are applied separately with respect to each publicly-traded partnership. Consequently, any passive losses we generate will be available to offset only passive income generated by us. Passive losses that exceed a common unitholder's share of passive income we generate may be deducted in full when the unitholder disposes of all of his units in a fully taxable transaction with an unrelated party. The passive loss rules generally are applied after other applicable limitations on deductions, including the at risk and basis limitations.Limitations on Interest Deductions. The deductibility of a non-corporate taxpayer's "investment interest expense" generally is limited to the amount of that taxpayer's "net investment income." Investment interest expense includes:

•: interest on indebtedness properly allocable to property held for investment;
•: our interest expense allocated against portfolio income; and
•: the portion of interest expense incurred to purchase or carry an interest in a passive activity to the extent allocable against portfolio income.

The computation of a common unitholder's investment interest expense will take into account interest on any margin account borrowing or other loan incurred to purchase or carry a common unit. Net investment income includes gross income from property held for investment and amounts treated as portfolio income under the passive loss rules, less deductible expenses, other than interest, directly connected with the production of investment income. Net investment income generally does not include qualified dividend income (if applicable) or gains attributable to the disposition of property held for investment. A common unitholder's share of a publicly traded partnership's portfolio income and, according to the IRS, net passive income will be treated as investment income for purposes of the investment interest expense limitation.

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Entity-Level Collections of Unitholder Taxes. If we are required or elect under applicable law to pay any federal, state, local or non-U.S. tax on behalf of any common unitholder or our general partner or any former common unitholder, we are authorized to treat the payment as a distribution of cash to the relevant common unitholder or general partner. Where the tax is payable on behalf of all the unitholders or we cannot determine the specific unitholder on whose behalf the tax is payable, we are authorized to treat the payment as a distribution to all current common unitholders. We are authorized to amend our Partnership Agreement in the manner necessary to maintain the uniformity of intrinsic tax characteristics of common units and to adjust later distributions, so that after giving effect to these distributions, the priority and characterization of distributions otherwise applicable under our Partnership Agreement is maintained as nearly as is practicable. Payments by us as described above could give rise to an overpayment of tax on behalf of an individual common unitholder in which event the common unitholder may be entitled to claim a refund of the overpayment amount. Unitholders are urged to consult their tax advisors to determine the consequences to them of any tax payment we make on their behalf.

Allocation of Income, Gain, Loss and Deduction. In general, our items of income, gain, loss and deduction will be allocated among the common unitholders in accordance with their percentage interests in us. Specified items of our income, gain, loss and deduction will be allocated under Section 704(c) of the Code (or the principles of Section 704(c) of the Code) to account for any difference between the tax basis and fair market value of our assets at the time such assets are contributed to us and at the time of any subsequent offering of our units (a "Book-Tax Disparity"). As a result, the federal income tax burden associated with any Book-Tax Disparity immediately prior to an offering generally will be borne by our partners holding interests in us prior to such offering. In addition, items of recapture income will be specifically allocated to the extent possible to the common unitholder who was allocated the deduction giving rise to that recapture income in order to minimize the recognition of ordinary income by other unitholders. Finally, although we do not expect that our operations will result in the creation of negative capital accounts, if negative capital accounts nevertheless result, items of our income and gain will be allocated in an amount and manner sufficient to eliminate the negative balance as quickly as possible.

An allocation of items of our income, gain, loss or deduction, other than an allocation required by the Code to a Book-Tax Disparity will generally be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction only if the allocation has substantial economic effect. In any other case, a partner's share of an item will be determined on the basis of his interest in us, which will be determined by taking into account all the facts and circumstances, including:

•: his relative contributions to us;
•: the interests of all the partners in profits and losses;
•: the interest of all the partners in cash flow; and
•: the rights of all the partners to distributions of capital upon liquidation.

Vinson & Elkins L.L.P. is of the opinion that, with the exception of the issues described in "—Section 754 Election" and "—Disposition of Common Units—Allocations Between Transferors and Transferees," allocations under our Partnership Agreement will be given effect for federal income tax purposes in determining a partner's share of an item of income, gain, loss or deduction.

Treatment of Securities Loans. A common unitholder whose common units are the subject of a securities loan (e.g., a loan to a "short seller" to cover a short sale of units) may be considered as having disposed of those common units. If so, he would no longer be treated for tax purposes as a

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partner with respect to those common units during the period of the loan and may recognize gain or loss from the disposition. As a result, during this period:

•: any of our income, gain, loss or deduction with respect to those common units would not be reportable by the common unitholder;
•: any cash distributions received by the common unitholder as to those common units would be fully taxable; and
•: all of these distributions would appear to be ordinary income.

Due to a lack of controlling authority, Vinson & Elkins L.L.P. has not rendered an opinion regarding the tax treatment of a common unitholder that enters into a securities loan with respect to his units; Common unitholders desiring to assure their status as partners and avoid the risk of income recognition from a loan of their units are urged to modify any applicable brokerage account agreements to prohibit their brokers from borrowing and lending their common units. The IRS has announced that it is studying issues relating to the tax treatment of short sales of partnership interests. Please also read "—Disposition of Common Units—Recognition of Gain or Loss."

Tax Rates. Beginning January 1, 2013, the highest marginal U.S. federal income tax rates for individuals applicable to ordinary income and long-term capital gains (generally, gains from the sale or exchange of certain investment assets held for more than one year) are 39.6% and 20%, respectively. These rates are subject to change by new legislation at any time.

In addition, a 3.8% Medicare tax on certain net investment income earned by individuals, estates, and trusts applies for taxable years beginning after December 31, 2012. For these purposes, net investment income generally includes a unitholder's allocable share of our income and gain realized by a unitholder from a sale of units. In the case of an individual, the tax will be imposed on the lesser of (i) the unitholder's net investment income from all investments, or (ii) the amount by which the unitholder's modified adjusted gross income exceeds $250,000 (if the unitholder is married and filing jointly or a surviving spouse), $125,000 (if married filing separately) or $200,000 (if the unitholder is unmarried or in any other case). In the case of an estate or trust, the tax will be imposed on the lesser of (i) undistributed net investment income, or (ii) the excess adjusted gross income over the dollar amount at which the highest income tax bracket applicable to an estate or trust begins.

Section 754 Election. We have made the election permitted by Section 754 of the Code that permits us to adjust the tax bases in our assets as to specific purchasers of our units under Section 743(b) of the Code. The Section 743(b) adjustment separately applies to each purchaser of units based upon the values and bases of our assets at the time of the relevant purchase, and the adjustment will reflect the purchase price paid. The Section 743(b) adjustment does not apply to a person who purchases units directly from us.

Under our Partnership Agreement, we are authorized to take a position to preserve the uniformity of units even if that position is not consistent with applicable Treasury Regulations. A literal application of Treasury Regulations governing a 743(b) adjustment attributable to properties depreciable under Section 167 of the Code may give rise to differences in the taxation of unitholders purchasing units from us and unitholders purchasing from other unitholders. If we have any such properties, we intend to adopt methods employed by other publicly traded partnerships to preserve the uniformity of units, even if inconsistent with existing Treasury Regulations, and Vinson & Elkins L.L.P. has not opined on the validity of this approach. Please read "—Uniformity of Common Units."

The IRS may challenge the positions we adopt with respect to depreciating or amortizing the Section 743(b) adjustment we take to preserve the uniformity of units due to lack of controlling authority. Because a unitholder's tax basis for its units is reduced by its share of our items of deduction or loss, any position we take that understates deductions will overstate a unitholder's basis in its units,

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and may cause the unitholder to understate gain or overstate loss on any sale of such units. Please read "—Disposition of Common Units—Recognition of Gain or Loss." If a challenge to such treatment were sustained, the gain from the sale of units may be increased without the benefit of additional deductions.

The calculations involved in the Section 754 election are complex and will be made on the basis of assumptions as to the value of our assets and other matters. The IRS could seek to reallocate some or all of any Section 743(b) adjustment we allocated to our assets subject to depreciation to goodwill or nondepreciable assets. Goodwill, as an intangible asset, is generally nonamortizable or amortizable over a longer period of time or under a less accelerated method than our tangible assets. We cannot assure any unitholder that the determinations we make will not be successfully challenged by the IRS or that the resulting deductions will not be reduced or disallowed altogether. Should the IRS require a different tax basis adjustment to be made, and should, in our opinion, the expense of compliance exceed the benefit of the election, we may seek permission from the IRS to revoke our Section 754 election. If permission is granted, a subsequent purchaser of units may be allocated more income than it would have been allocated had the election not been revoked.

Tax Treatment of Operations

Accounting Method and Taxable Year. We will use the year ending December 31 as our taxable year and the accrual method of accounting for federal income tax purposes. Each common unitholder will be required to include in income his share of our income, gain, loss and deduction for our taxable year ending within or with his taxable year. In addition, a common unitholder who has a taxable year ending on a date other than December 31 and who disposes of all of his common units following the close of our taxable year but before the close of his taxable year must include his share of our income, gain, loss and deduction in income for his taxable year, with the result that he will be required to include in his taxable income for his taxable year his share of more than twelve months of our income, gain, loss and deduction. Please read "—Disposition of Common Units—Allocations Between Transferors and Transferees."

Tax Basis, Depreciation and Amortization. The tax basis of our assets will be used for purposes of computing depreciation and cost recovery deductions and, ultimately, gain or loss on the disposition of these assets. If we dispose of depreciable property by sale, foreclosure or otherwise, all or a portion of any gain, determined by reference to the amount of depreciation deductions previously taken, may be subject to the recapture rules and taxed as ordinary income rather than capital gain. Similarly, a unitholder who has taken cost recovery or depreciation deductions with respect to property we own will likely be required to recapture some or all of those deductions as ordinary income upon a sale of his interest in us. Please read "—Tax Consequences of Common Unit Ownership—Allocation of Income, Gain, Loss and Deduction" and "—Disposition of Common Units—Recognition of Gain or Loss."

The costs incurred in offering and selling our common units (called "syndication expenses") must be capitalized and cannot be deducted currently, ratably, or upon our termination. While there are uncertainties regarding the classification of costs as organization expenses, which may be amortized by us, and as syndication expenses, which may not be amortized by us, the underwriting discounts and commissions we incur will be treated as syndication expenses.

Valuation and Tax Basis of Our Properties. The federal income tax consequences of the ownership and disposition of common units will depend in part on our estimates of the relative fair market values, and the tax bases, of our assets. Although we may from time to time consult with professional appraisers regarding valuation matters, we will make many of the relative fair market value estimates ourselves. These estimates and determinations of basis are subject to challenge and will not be binding on the IRS or the courts. If the estimates of fair market value or basis are later found to be incorrect, the character and amount of items of income, gain, loss or deduction previously reported by common unitholders could change, and common unitholders could be required to adjust their tax liability for prior years and incur interest and penalties with respect to those adjustments.

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Oil and Natural Gas Taxation

Depletion Deductions. Subject to the limitations on deductibility of losses discussed above (please read "—Tax Consequences of Common Unit Ownership—Limitations on Deductibility of Losses"), common unitholders will be entitled to deductions for the greater of either cost depletion or (if otherwise allowable) percentage depletion with respect to our oil and natural gas interests. Although the Code requires each common unitholder to compute his own depletion allowance and maintain records of his share of the adjusted tax basis of the underlying property for depletion and other purposes, we intend to furnish each of our common unitholders with information relating to this computation for federal income tax purposes. Each common unitholder, however, remains responsible for calculating his own depletion allowance and maintaining records of his share of the adjusted tax basis of the underlying property for depletion and other purposes.

Percentage depletion is generally available with respect to common unitholders who qualify under the independent producer exemption contained in Section 613A(c) of the Code. For this purpose, an independent producer is a person not directly or indirectly involved in the retail sale of oil, natural gas, or derivative contracts or the operation of a major refinery. Percentage depletion is calculated as an amount generally equal to 15% (and, in the case of marginal production, potentially a higher percentage) of the common unitholder's gross income from the depletable property for the taxable year. The percentage depletion deduction with respect to any property is limited to 100% of the taxable income of the common unitholder from the property for each taxable year, computed without the depletion allowance. A common unitholder that qualifies as an independent producer may deduct percentage depletion only to the extent the common unitholder's average net daily production of domestic crude oil, or the natural gas equivalent, does not exceed 1,000 barrels. This depletable amount may be allocated between natural gas and oil production, with 6,000 cubic feet of domestic natural gas production regarded as equivalent to one barrel of crude oil. The 1,000-barrel limitation must be allocated among the independent producer and controlled or related persons and family members in proportion to the respective production by such persons during the period in question.

In addition to the foregoing limitations, the percentage depletion deduction otherwise available is limited to 65% of a common unitholder's total taxable income from all sources for the year, computed without the depletion allowance, net operating loss carrybacks, or capital loss carrybacks. Any percentage depletion deduction disallowed because of the 65% limitation may be deducted in the following taxable year if the percentage depletion deduction for such year plus the deduction carryover does not exceed 65% of the common unitholder's total taxable income for that year. The carryover period resulting from the 65% net income limitation is unlimited.

Common unitholders that do not qualify under the independent producer exemption are generally restricted to depletion deductions based on cost depletion. Cost depletion deductions are calculated by (a) dividing the common unitholder's share of the adjusted tax basis in the underlying mineral property by the number of mineral common units (barrels of oil and thousand cubic feet, or Mcf, of natural gas) remaining as of the beginning of the taxable year and (b) multiplying the result by the number of mineral common units sold within the taxable year. The total amount of deductions based on cost depletion cannot exceed the common unitholder's share of the total adjusted tax basis in the property.

All or a portion of any gain recognized by a common unitholder as a result of either the disposition by us of some or all of our oil and natural gas interests or the disposition by the common unitholder of some or all of his common units may be taxed as ordinary income to the extent of recapture of depletion deductions, except for percentage depletion deductions in excess of the tax basis of the property. The amount of the recapture is generally limited to the amount of gain recognized on the disposition.

The foregoing discussion of depletion deductions does not purport to be a complete analysis of the complex legislation and Treasury Regulations relating to the availability and calculation of depletion

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deductions by the common unitholders. Further, because depletion is required to be computed separately by each common unitholder and not by our partnership, no assurance can be given, and counsel is unable to express any opinion, with respect to the availability or extent of percentage depletion deductions to the common unitholders for any taxable year. Moreover, the availability of percentage depletion may be reduced or eliminated if recently proposed (or similar) tax legislation is enacted. For a discussion of such legislative proposals, please read "—Recent Legislative Developments." We encourage each prospective common unitholder to consult his tax advisor to determine whether percentage depletion would be available to him.

Deductions for Intangible Drilling and Development Costs. We will elect to currently deduct intangible drilling and development costs ("IDCs"). IDCs generally include our expenses for wages, fuel, repairs, hauling, supplies and other items that are incidental to, and necessary for, the drilling and preparation of wells for the production of oil or natural gas. The option to currently deduct IDCs applies only to those items that do not have a salvage value.

Although we will elect to currently deduct IDCs, each common unitholder will have the option of either currently deducting IDCs or capitalizing all or part of the IDCs and amortizing them on a straight-line basis over a 60-month period, beginning with the taxable month in which the expenditure is made. If a common unitholder makes the election to amortize the IDCs over a 60-month period, no IDC preference amount in respect of those IDCs will result for alternative minimum tax purposes.

Integrated oil companies must capitalize 30% of all their IDCs (other than IDCs paid or incurred with respect to oil and natural gas wells located outside of the United States) and amortize these IDCs over 60 months beginning in the month in which those costs are paid or incurred. If the taxpayer ceases to be an integrated oil company, it must continue to amortize those costs as long as it continues to own the property to which the IDCs relate. An "integrated oil company" is a taxpayer that has economic interests in oil or natural gas properties and also carries on substantial retailing or refining operations. An oil or natural gas producer is deemed to be a substantial retailer or refiner if it is subject to the rules disqualifying retailers and refiners from taking percentage depletion. To qualify as an "independent producer" that is not subject to these IDC deduction limits, a common unitholder, either directly or indirectly through certain related parties, may not be involved in the refining of more than 75,000 barrels of oil (or the equivalent of natural gas) on average for any day during the taxable year or in the retail marketing of oil and natural gas products exceeding $5 million per year in the aggregate.

IDCs previously deducted that are allocable to property (directly or through ownership of an interest in a partnership) and that would have been included in the adjusted tax basis of the property had the IDC deduction not been taken are recaptured to the extent of any gain realized upon the disposition of the property or upon the disposition by a common unitholder of interests in us. Recapture is generally determined at the common unitholder level. Where only a portion of the recapture property is sold, any IDCs related to the entire property are recaptured to the extent of the gain realized on the portion of the property sold. In the case of a disposition of an undivided interest in a property, a proportionate amount of the IDCs with respect to the property is treated as allocable to the transferred undivided interest to the extent of any gain recognized. Please read "—Disposition of Common Units—Recognition of Gain or Loss."

The election to currently deduct IDCs may be restricted or eliminated if recently proposed (or similar) tax legislation is enacted. For a discussion of such legislative proposals, please read "—Recent Legislative Developments."

Deduction for U.S. Production Activities. Subject to the limitations on the deductibility of losses discussed above and the limitations discussed below, common unitholders will be entitled to a deduction, herein referred to as the Section 199 deduction, equal to 9% of the lesser of (1) our qualified production activities income that is allocated to such common unitholder or (2) the common

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unitholder's taxable income, but not to exceed 50% of such common unitholder's IRS Form W-2 wages for the taxable year allocable to domestic production gross receipts.

Qualified production activities income is generally equal to gross receipts from domestic production activities reduced by cost of goods sold allocable to those receipts, other expenses directly associated with those receipts, and a share of other deductions, expenses, and losses that are not directly allocable to those receipts or another class of income. The products produced must be manufactured, produced, grown, or extracted in whole or in significant part by the taxpayer in the United States.

For a partnership, the Section 199 deduction is determined at the partner level. To determine his Section 199 deduction, each common unitholder will aggregate his share of the qualified production activities income allocated to him from us with the common unitholder's qualified production activities income from other sources. Each common unitholder must take into account his distributive share of the expenses allocated to him from our qualified production activities regardless of whether we otherwise have taxable income. However, our expenses that otherwise would be taken into account for purposes of computing the Section 199 deduction are taken into account only if and to the extent the common unitholder's share of losses and deductions from all of our activities is not disallowed by the tax basis rules, the at-risk rules or the passive activity loss rules. Please read "—Tax Consequences of Common Unit Ownership—Limitations on Deductibility of Losses."

The amount of a common unitholder's Section 199 deduction for each year is limited to 50% of the IRS Form W-2 wages actually or deemed paid by the common unitholder during the calendar year that are deducted in arriving at qualified production activities income. Each common unitholder is treated as having been allocated IRS Form W-2 wages from us equal to the common unitholder's allocable share of our wages that are deducted in arriving at qualified production activities income for that taxable year. It is not anticipated that we or our subsidiaries will pay material wages that will be allocated to our common unitholders, and thus a common unitholder's ability to claim the Section 199 deduction may be limited.

A unitholder's otherwise allowable Section 199 deduction for each taxable year is reduced by 3% of the least of (1) the oil related qualified production activities income of the taxpayer for the taxable year, (2) the qualified production activities income of the taxpayer for the taxable year, or (3) the taxpayer's taxable income for the taxable year (determined without regard to any Section 199 deduction). For this purpose, the term "oil related qualified production activities income" means the qualified production activities income attributable to the production, refining, processing, transportation, or distribution of oil, gas, or any primary production thereof. We expect that most or all of our qualified production activities income will consist of oil related qualified production activities income.

This discussion of the Section 199 deduction does not purport to be a complete analysis of the complex legislation and Treasury authority relating to the calculation of domestic production gross receipts, qualified production activities income, or IRS Form W-2 wages, or how such items are allocated by us to common unitholders. Further, because the Section 199 deduction is required to be computed separately by each common unitholder, no assurance can be given, and counsel is unable to express any opinion, as to the availability or extent of the Section 199 deduction to the common unitholders. Moreover, the availability of Section 199 deductions may be reduced or eliminated if recently proposed (or similar) tax legislation is enacted. For a discussion of such legislative proposals, please read "—Recent Legislative Developments." Each prospective common unitholder is encouraged to consult his tax advisor to determine whether the Section 199 deduction would be available to him.

Lease Acquisition Costs. The cost of acquiring oil and natural gas lease or similar property interests is a capital expenditure that must be recovered through depletion deductions if the lease is productive. If a lease is proved worthless and abandoned, the cost of acquisition less any depletion

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claimed may be deducted as an ordinary loss in the year the lease becomes worthless. Please read "—Tax Treatment of Operations—Oil and Natural Gas Taxation—Depletion Deductions."

Geophysical Costs. The cost of geophysical exploration incurred in connection with the exploration and development of oil and natural gas properties in the United States are deducted ratably over a 24-month period beginning on the date that such expense is paid or incurred. This 24-month period is extended to 7 years in the case of major integrated oil companies. Moreover, the 24-month period may be similarly extended for all taxpayers if recently proposed tax (or similar) legislation is enacted. For a discussion of such legislative proposals, please read "—Recent Legislative Developments."

Operating and Administrative Costs. Amounts paid for operating a producing well are deductible as ordinary business expenses, as are administrative costs to the extent they constitute ordinary and necessary business expenses that are reasonable in amount.

Recent Legislative Developments.

Both the Obama Administration's budget proposal for fiscal year 2013 and other recently introduced legislation include proposals that would, among other things, eliminate or reduce certain key U.S. federal income tax incentives currently available to oil and natural gas exploration and production companies. These changes include, but are not limited to, (1) the repeal of the percentage depletion allowance for oil and natural gas properties, (2) the elimination of the deduction for intangible drilling and development costs and certain environmental clean-up costs, (3) the elimination of the deduction for certain domestic production activities, and (4) the extension of the amortization period for certain geological and geophysical expenditures. It is unclear whether these or similar changes will be enacted and, if enacted, how soon any such changes could become effective. The passage of any legislation as a result of these proposals or any other similar changes in U.S. federal income tax laws could eliminate or postpone certain tax deductions that are currently available with respect to oil and natural gas exploration and development, and any such change could increase the taxable income allocable to common unitholders and negatively impact the value of an investment in our common units.

Disposition of Common Units

Recognition of Gain or Loss. Gain or loss will be recognized on a sale of common units equal to the difference between the amount realized and the common unitholder's tax basis in the common units sold. A common unitholder's amount realized generally will equal the sum of the cash or the fair market value of other property received by him plus his share of our nonrecourse liabilities with respect to such units. Because the amount realized includes a common unitholder's share of our nonrecourse liabilities, the gain recognized on the sale of common units could result in a tax liability in excess of any cash received from the sale.

Except as noted below, gain or loss recognized by a common unitholder on the sale or exchange of a common unit held for more than one year will generally be taxable as long-term capital gain or loss. However, gain or loss recognized on the disposition of common units will be separately computed and taxed as ordinary income or loss under Section 751 of the Code to the extent attributable to Section 751 Assets, such as depreciation recapture. Ordinary income attributable to Section 751 Assets may exceed net taxable gain realized upon the sale of a common unit and may be recognized even if there is a net taxable loss realized on the sale of a common unit. Thus, a common unitholder may recognize both ordinary income and capital gain or loss upon a sale of common units. Net capital loss may offset capital gains, in the case of individuals, up to $3,000 of ordinary income per year.

The IRS has ruled that a partner who acquires interests in a partnership in separate transactions must combine those interests and maintain a single adjusted tax basis for all those interests. Upon a sale or other disposition of less than all of those interests, a portion of that tax basis must be allocated

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to the interests sold using an "equitable apportionment" method, which generally means that the tax basis allocated to the interest sold equals an amount that bears the same relation to the partner's tax basis in his entire interest in the partnership as the value of the interest sold bears to the value of the partner's entire interest in the partnership. Treasury Regulations under Section 1223 of the Code allow a selling common unitholder who can identify common units transferred with an ascertainable holding period to elect to use the actual holding period of the common units transferred. Thus, according to the ruling discussed above, a common unitholder will be unable to select high or low basis common units to sell as would be the case with corporate stock, but, according to the Treasury Regulations, he may designate specific common units sold for purposes of determining the holding period of common units transferred. A common unitholder electing to use the actual holding period of common units transferred must consistently use that identification method for all subsequent sales or exchanges of common units. A common unitholder considering the purchase of additional common units or a sale of common units purchased in separate transactions is urged to consult his tax advisor as to the possible consequences of this ruling and application of the Treasury Regulations.

Specific provisions of the Code affect the taxation of some financial products and securities, including partnership interests, by treating a taxpayer as having sold an "appreciated" financial position, including a partnership interest with respect to which gain would be recognized if it were sold, assigned or terminated at its fair market value, in the event the taxpayer or a related person enters into:

•: a short sale;
•: an offsetting notional principal contract; or
•: a futures or forward contract with respect to the partnership interest or substantially identical property.

Moreover, if a taxpayer has previously entered into a short sale, an offsetting notional principal contract or a futures or forward contract with respect to the partnership interest, the taxpayer will be treated as having sold that position if the taxpayer or a related person then acquires the partnership interest or substantially identical property. The Secretary of the Treasury is also authorized to issue regulations that treat a taxpayer that enters into transactions or positions that have substantially the same effect as the preceding transactions as having constructively sold the financial position.

Allocations Between Transferors and Transferees. In general, our taxable income or loss will be determined annually, will be prorated on a monthly basis and will be subsequently apportioned among the common unitholders in proportion to the number of common units owned by each of them as of the opening of the applicable exchange on the first business day of the month (the "Allocation Date"). However, gain or loss realized on a sale or other disposition of our assets other than in the ordinary course of business or, in the discretion of the general partner, any other extraordinary item of income, gain, loss or deduction will be allocated among the common unitholders on the Allocation Date in the month in which such income, gain, loss or deduction is recognized. As a result, a common unitholder transferring common units may be allocated income, gain, loss and deduction realized after the date of transfer.

Although simplifying conventions are contemplated by the Code, and most publicly traded partnerships use similar simplifying conventions, the use of this method may not be permitted under existing Treasury Regulations. Recently, however, the Department of the Treasury and the IRS issued proposed Treasury Regulations that provide a safe harbor pursuant to which a publicly traded partnership may use a similar monthly simplifying convention to allocate tax items among transferor and transferee common unitholders, although such tax items must be prorated on a daily basis. Nonetheless, the proposed regulations do not specifically authorize the use of the proration method we have adopted. Accordingly, Vinson & Elkins L.L.P. is unable to opine on the validity of this method of allocating income and deductions between transferor and transferee common unitholders. If this

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method is not allowed under the final Treasury Regulations, or only applies to transfers of less than all of the common unitholder's interest, our taxable income or losses could be reallocated among the common unitholders. We are authorized to revise our method of allocation between transferor and transferee common unitholders, as well as common unitholders whose interests vary during a taxable year, to conform to a method permitted under future Treasury Regulations.

A common unitholder who disposes of common units prior to the record date set for a cash distribution for that quarter will be allocated items of our income, gain, loss and deduction attributable to that quarter but will not be entitled to receive that cash distribution for that period.

Notification Requirements. A common unitholder who sells or purchases any of his common units is generally required to notify us in writing of that transaction within 30 days after the transaction (or, if earlier, January 15 of the year following the transaction in the case of a seller). Upon receiving such notifications, we are required to notify the IRS of that transaction and to furnish specified information to the transferor and transferee. Failure to notify us of a transfer of units may, in some cases, lead to the imposition of penalties. However, these reporting requirements do not apply to a sale by an individual who is a citizen of the United States and who effects the sale through a broker who will satisfy such requirements.

Constructive Termination. We will be considered to have constructively terminated our partnership for federal income tax purposes upon the sale or exchange of 50% or more of the total interests in our capital and profits within a twelve-month period. For such purposes, multiple sales of the same unit are counted only once. Our termination results in the closing of our taxable year for all unitholders. In the case of a unitholder reporting on a taxable year other than a fiscal year ending December 31, the closing of our taxable year may result in more than twelve months of our taxable income or loss being includable in his taxable income for the year of termination. Our termination currently would not affect our consolidated financial statements or our classification as a partnership for federal income tax purposes, but instead, we would be treated as a new partnership for tax purposes.

A technical termination occurring on a date other than December 31 generally would require that we file two tax returns for one fiscal year, and the cost of the preparation of these returns will be borne by all unitholders. However, pursuant to an IRS relief procedure, the IRS may allow a constructively terminated partnership to provide a single Schedule K-1 for the calendar year in which a termination occurs. Following a constructive termination, we would be required to make new tax elections, including a new election under Section 754 of the Code, and the termination would result in a deferral of our deductions for depreciation. A termination could also result in penalties if we were unable to determine that the termination had occurred. Moreover, a termination may either accelerate the application of, or subject us to, any tax legislation enacted before the termination that would not otherwise have been applied to us as a continuing as opposed to a terminating partnership

Uniformity of Common Units

Because we cannot match transferors and transferees of common units and for other reasons, we must maintain uniformity of the economic and tax characteristics of the common units to a purchaser of these common units. In the absence of uniformity, we may be unable to completely comply with a number of federal income tax requirements. Any non-uniformity could have a negative impact on the value of the common units. Please read "—Tax Consequences of Common Unit Ownership—Section 754 Election."

Our Partnership Agreement permits our general partner to take positions in filing our tax returns that preserve the uniformity of our common units. These positions may include reducing the depreciation, amortization or loss deductions to which a unitholder would otherwise be entitled or reporting a slower amortization of Section 743(b) adjustments for some unitholders than that to which

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they would otherwise be entitled. Vinson & Elkins L.L.P. is unable to opine as to validity of such filing positions.

A unitholder's basis in units is reduced by its share of our deductions (whether or not such deductions were claimed on an individual income tax return) so that any position that we take that understates deductions will overstate the unitholder's basis in his common units, and may cause the unitholder to understate gain or overstate loss on any sale of such common units. Please read "—Disposition of Common Units—Recognition of Gain or Loss" above and "—Tax Consequences of Common Unit Ownership—Section 754 Election" above. The IRS may challenge one or more of any positions we take to preserve the uniformity of units. If such a challenge were sustained, the uniformity of units might be affected, and, under some circumstances, the gain from the sale of units might be increased without the benefit of additional deductions.

Tax-Exempt Organizations and Other Investors

Ownership of common units by employee benefit plans, other tax-exempt organizations, non-resident aliens, non-U.S. corporations and other non-U.S. persons raises issues unique to those investors and, as described below, may have substantially adverse tax consequences to them. Prospective unitholders that are tax-exempt entities or non-U.S. persons should consult their tax advisors before investing in our common units.

Employee benefit plans and most other organizations exempt from federal income tax, including IRAs and other retirement plans, are subject to federal income tax on unrelated business taxable income. Virtually all of our income will be unrelated business taxable income and will be taxable to a tax-exempt unitholder.

Non-resident aliens and foreign corporations, trusts or estates that own common units will be considered to be engaged in business in the United States because of the ownership of common units. Consequently, they will be required to file federal tax returns to report their share of our income, gain, loss or deduction and pay federal income tax at regular rates on their share of our net income or gain. Moreover, under rules applicable to publicly traded partnerships, distributions to non-U.S. common unitholders are subject to withholding at the highest applicable effective tax rate. Each non-U.S. common unitholder must obtain a taxpayer identification number from the IRS and submit that number to our transfer agent on a Form W-8BEN or applicable substitute form in order to obtain credit for these withholding taxes. A change in applicable law may require us to change these procedures.

In addition, because a foreign corporation that owns common units will be treated as engaged in a United States trade or business, that corporation may be subject to the U.S. branch profits tax at a rate of 30%, in addition to regular federal income tax, on its share of our income and gain, to the extent reflected in earnings and profits, and as adjusted for changes in the foreign corporation's "U.S. net equity." That tax may be reduced or eliminated by an income tax treaty between the United States and the country in which the foreign corporate common unitholder is a "qualified resident." In addition, this type of common unitholder is subject to special information reporting requirements under Section 6038C of the Code.

A non-U.S. common unitholder who sells or otherwise disposes of a common unit will be subject to U.S. federal income tax on gain realized from the sale or disposition of that common unit to the extent the gain is effectively connected with a U.S. trade or business of the non-U.S. common unitholder. Under a ruling published by the IRS interpreting the scope of "effectively connected income," part or all of a non-U.S. common unitholder's gain may be treated as effectively connected with that common unitholder's indirect U.S. trade or business constituted by its investment in us. Moreover, under the Foreign Investment in Real Property Tax Act, a non-U.S. common unitholder generally will be subject to U.S. federal income tax upon the sale or disposition of a common unit if

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(i) he owned (directly or constructively applying certain attribution rules) more than 5% of our common units at any time during the five-year period ending on the date of such disposition and (ii) 50% or more of the fair market value of all of our assets consisted of U.S. real property interests at any time during the shorter of the period during which such common unitholder held the common units or the 5-year period ending on the date of disposition. More than 50% of our assets may consist of U.S. real property interests and we do not expect that to change in the foreseeable future. Therefore, non-U.S. common unitholders may be subject to federal income tax on gain from the sale or disposition of their common units.

Administrative Matters

Information Returns and Audit Procedures. We intend to furnish to each common unitholder, within 90 days after the close of each taxable year, specific tax information, including a Schedule K-1, which describes his share of our income, gain, loss and deduction for our preceding taxable year. In preparing this information, which will not be reviewed by counsel, we will take various accounting and reporting positions, some of which have been mentioned earlier, to determine each common unitholder's share of income, gain, loss and deduction. We cannot assure you that those positions will yield a result that conforms to the requirements of the Internal Revenue Code, Treasury Regulations or administrative interpretations of the IRS. The IRS may audit our federal income tax information returns. Neither we nor Vinson & Elkins L.L.P. can assure prospective common unitholders that the IRS will not successfully challenge the positions we adopt, and such a challenge could adversely affect the value of the common units.

The IRS may audit our federal income tax information returns. Adjustments resulting from an IRS audit may require each common unitholder to adjust a prior year's tax liability, and may result in an audit of his return. Any audit of a common unitholder's return could result in adjustments unrelated to our returns.

Publicly traded partnerships generally are treated as entities separate from their owners for purposes of federal income tax audits, judicial review of administrative adjustments by the IRS and tax settlement proceedings. The tax treatment of partnership items of income, gain, loss and deduction are determined in a partnership proceeding rather than in separate proceedings of the partners. The Code requires that one partner be designated as the "Tax Matters Partner" for these purposes and our Partnership Agreement designates our general partner.

The Tax Matters Partner can extend the statute of limitations for assessment of tax deficiencies against common unitholders for items in our returns. The Tax Matters Partner may bind a common unitholder with less than a 1% profits interest in us to a settlement with the IRS unless that common unitholder elects, by filing a statement with the IRS, not to give that authority to the Tax Matters Partner. The Tax Matters Partner may seek judicial review, by which all the common unitholders are bound, of a final partnership administrative adjustment and, if the Tax Matters Partner fails to seek judicial review, judicial review may be sought by any common unitholder having at least a 1% interest in profits or by any group of common unitholders having in the aggregate at least a 5% interest in profits. However, only one action for judicial review may go forward, and each common unitholder with an interest in the outcome may participate in that action.

A common unitholder must file a statement with the IRS identifying the treatment of any item on his federal income tax return that is not consistent with the treatment of the item on our return. Intentional or negligent disregard of this consistency requirement may subject a common unitholder to substantial penalties.

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Nominee Reporting. Persons who hold an interest in us as a nominee for another person are required to furnish to us:

(a) the name, address and taxpayer identification number of the beneficial owner and the nominee;

(b) a statement regarding whether the beneficial owner is:

1. a non-U.S. person;

2. a non-U.S. government, an international organization or any wholly-owned agency or instrumentality of either of the foregoing; or

3. a tax-exempt entity;

(d) specific information including the dates of acquisitions and transfers, means of acquisitions and transfers, and acquisition cost for purchases, as well as the amount of net proceeds from sales.

Brokers and financial institutions are required to furnish additional information, including whether they are U.S. persons and specific information on common units they acquire, hold or transfer for their own account. A penalty of $100 per failure, up to a maximum of $1.5 million per calendar year, is imposed by the Internal Revenue Code for failure to report that information to us. The nominee is required to supply the beneficial owner of the common units with the information furnished to us.

Accuracy-Related Penalties. An additional tax equal to 20% of the amount of any portion of an underpayment of tax that is attributable to one or more specified causes, including negligence or disregard of rules or regulations, substantial understatements of income tax and substantial valuation misstatements, is imposed by the Code. No penalty will be imposed, however, for any portion of an underpayment if it is shown that there was a reasonable cause for the underpayment of that portion and that the taxpayer acted in good faith regarding the underpayment of that portion.

State, Local, Non-U.S. and Other Tax Considerations

In addition to federal income taxes, unitholders may be subject to other taxes, including state and local and non-U.S. income taxes, unincorporated business taxes, and estate, inheritance or intangibles taxes that may be imposed by the various jurisdictions in which we conduct business or own property now or in the future or in which you are a resident. We currently conduct business or own property in several states. Some or all of these states may impose an income tax on nonresident partners of partnerships doing business within the state, and we may also own property or do business in other states in the future that impose income or similar taxes on nonresident persons owning an interest in us. Although an analysis of those various taxes is not presented here, each prospective common unitholder should consider their potential impact on his investment in us.

It is the responsibility of each common unitholder to investigate the legal and tax consequences, under the laws of pertinent jurisdictions, of his investment in us. We strongly recommend that each prospective common unitholder consult, and depend upon, his tax counsel or other advisor with regard to those matters. Further, it is the responsibility of each common unitholder to file all state, local and non-U.S., as well as U.S., federal tax returns that may be required of him. Vinson & Elkins L.L.P. has not rendered an opinion on the state, local, alternative minimum tax or non-U.S. tax consequences of an investment in us.

Tax Consequences of Ownership of Debt Securities

A description of the material federal income tax consequences of the acquisition, ownership and disposition of debt securities will be set forth on the prospectus supplement relating to the offering of debt securities.

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INVESTMENT IN EAGLE ROCK ENERGY PARTNERS, L.P. BY EMPLOYEE BENEFIT PLANS

An investment in our units or debt securities by an employee benefit plan is subject to certain additional considerations because the investments of these plans are subject to the fiduciary responsibility and prohibited transaction provisions of the Employee Retirement Income Security Act of 1974, as amended ("ERISA") and the restrictions imposed by Section 4975 of the Internal Revenue Code and provisions under any federal, state, local, non-U.S. or other laws or regulations that are similar to such provisions of the Internal Revenue Code or ERISA (collectively, "Similar Laws"). As used herein, the term "employee benefit plan" includes, but is not limited to, qualified pension, profit-sharing and stock bonus plans, Keogh plans, simplified employee pension plans and tax deferred annuities, IRAs and other arrangements established or maintained by an employer or employee organization, and entities whose underlying assets are considered to include "plan assets" of such plans, accounts and arrangements.

General Fiduciary Matters

ERISA and the Internal Revenue Code impose certain duties on persons who are fiduciaries of an employee benefit plan that is subject to Title I of ERISA or Section 4975 of the Internal Revenue Code (an "ERISA Plan") and prohibit certain transactions involving the assets of an ERISA Plan and its fiduciaries or other interested parties. Under ERISA and the Internal Revenue Code, any person who exercises any discretionary authority or control over the administration of an ERISA Plan or the management or disposition of the assets of an ERISA Plan, or who renders investment advice for a fee or other compensation to an ERISA plan, is generally considered to be a fiduciary of the ERISA Plan. In considering an investment in our units or debt securities, among other things, consideration should be given to:

•: whether the investment is prudent under Section 404(a)(1)(B) of ERISA and any other applicable Similar Laws;
•: whether in making the investment, the plan will satisfy the diversification requirements of Section 404(a)(1)(C) of ERISA and any other applicable Similar Laws; and
•: whether the investment will result in recognition of unrelated business taxable income by the plan and, if so, the potential after-tax investment return. Please read "Material Tax Consequences—Tax-Exempt Organizations and Other Investors."

The person with investment discretion with respect to the assets of an employee benefit plan should determine whether an investment in our units or debt securities is authorized by the appropriate governing instrument and is a proper investment for the plan.

Prohibited Transaction Issues

Section 406 of ERISA and Section 4975 of the Internal Revenue Code prohibit employee benefit plans, and IRAs that are not considered part of an employee benefit plan, from engaging in specified transactions involving "plan assets" with parties that, with respect to the plan, are "parties in interest" under ERISA or "disqualified persons" under the Internal Revenue Code. Accordingly, a fiduciary should consider whether a purchase of our common units is a prohibited transaction, unless an exemption is available. A party in interest or disqualified person who engages in a non-exempt prohibited transaction may be subject to excise taxes and other penalties and liabilities under ERISA and the Internal Revenue Code. In addition, the fiduciary of the ERISA Plan that engaged in such a non-exempt prohibited transaction may be subject to excise taxes, penalties and liabilities under ERISA and the Internal Revenue Code.

The acquisition and/or holding of debt securities by an ERISA Plan with respect to which we or the initial purchasers are considered a party in interest or a disqualified person, may constitute or

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result in a direct or indirect prohibited transaction under Section 406 of ERISA and/or Section 4975 of the Internal Revenue Code, unless the debt securities are acquired and held in accordance with an applicable statutory, class or individual prohibited transaction exemption. In this regard, the U.S. Department of Labor has issued prohibited transaction class exemptions, or PTCEs, that may apply to the acquisition, holding and, if applicable, conversion of the debt securities. These class exemptions include, without limitation, PTCE 84-14 respecting transactions determined by independent qualified professional asset managers, PTCE 90-1 respecting insurance company pooled separate accounts, PTCE 91-38 respecting bank collective investment funds, PTCE 95-60 respecting life insurance company general accounts and PTCE 96-23 respecting transactions determined by in-house asset managers. There can be no assurance that all of the conditions of any such exemptions will be satisfied. In addition, Section 408(b)(17) of ERISA and Section 4975(d)(20) of the Internal Revenue Code provide relief from the prohibited transaction provisions of ERISA and Section 4975 of the Internal Revenue Code for certain transactions, provided that (i) neither the issuer of the securities nor any of its affiliates (directly or indirectly) have or exercise any discretionary authority or control or render any investment advice with respect to the assets of any ERISA Plan involved in the transaction and (ii) the ERISA Plan pays no more than adequate consideration in connection with the transaction. Each of these PTCEs contains conditions and limitations on its application. Thus, the fiduciaries of an employee benefit plan that is considering acquiring and/or holding the notes in reliance on any of these, or any other, PTCEs should carefully review the PTCE and consult with their counsel to confirm that it is applicable. There can be no, and we do not provide any, assurance that all of the conditions of any such exemptions will be satisfied.

Because of the foregoing, our units or debt securities may not be purchased or held (or converted to equity securities, in the case of any convertible debt) by any person investing "plan assets" of any employee benefit plan, unless such purchase and holding (or conversion, if any) will not constitute a non-exempt prohibited transaction under ERISA or the Internal Revenue Code or similar violation of any applicable Similar Laws.

Representation

Accordingly, by acceptance of our units or debt securities, each purchaser and subsequent transferee of the units or debt securities will be deemed to have represented and warranted that either (i) no portion of the assets used by such purchaser or transferee to acquire and hold the units or debt securities constitutes assets of any employee benefit plan or (ii) the purchase and holding (and any conversion, if applicable) of the units or debt securities by such purchaser or transferee will not constitute a non-exempt prohibited transaction under Section 406 of ERISA or Section 4975 of the Internal Revenue Code or similar violation under any applicable Similar Laws.

Plan Asset Issues

In addition to considering whether the purchase of our units or debt securities is a prohibited transaction, a fiduciary of an employee benefit plan should consider whether the plan will, by investing in our units or debt securities, be deemed to own an undivided interest in our assets, with the result that our general partner also would be a fiduciary of the plan and our operations would be subject to the regulatory restrictions of ERISA, including its prohibited transaction rules, as well as the prohibited transaction rules of the Internal Revenue Code and any other applicable Similar Laws.

The Department of Labor regulations provide guidance with respect to whether, in certain circumstances, the assets of an entity in which employee benefit plans acquire equity interests would be

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deemed "plan assets." Under these regulations, an entity's assets would not be considered to be "plan assets" if, among other things:

(a) the equity interests acquired by the employee benefit plan are publicly offered securities—i.e., the equity interests are widely held by 100 or more investors independent of the issuer and each other, are freely transferable and are registered pursuant to certain provisions of the federal securities laws;

(b) the entity is an "operating company,"—i.e., it is primarily engaged in the production or sale of a product or service, other than the investment of capital, either directly or through a majority-owned subsidiary or subsidiaries; or

(c) there is no significant investment by benefit plan investors, which is defined to mean that less than 25% of the value of each class of equity interest, disregarding certain interests held by our general partner, its affiliates, and certain other persons, is held by employee benefit plans that are subject to part 4 of Title I of ERISA (which excludes governmental plans and non-electing church plans) and/or Section 4975 of the Internal Revenue Code and IRAs.

With respect to an investment in our units, we believe that our assets should not be considered "plan assets" under these regulations because it is expected that the investment will satisfy the requirements in (a) and (b) above and may also satisfy the requirement in (c) above (although we do not monitor the level of benefit plan investors as required for compliance with (c)). With respect to an investment in our debt securities, our assets should not be considered "plan assets" under these regulations because such securities are not equity securities or, even if they are considered equity securities under the Department of Labor regulations, it is expected that the investment will satisfy the requirements in (a) above and may satisfy the requirements in (b) above.

The foregoing discussion of issues arising for employee benefit plan investments under ERISA, the Internal Revenue Code and Similar Laws is general in nature and is not intended to be all inclusive, nor should it be construed as legal advice. In light of the complexity of these rules and the excise taxes, penalties and liabilities that may be imposed on persons involved in non-exempt prohibited transactions or other violations, plan fiduciaries contemplating a purchase of our units or debt securities should consult with their own counsel regarding the consequences under ERISA, the Internal Revenue Code and Similar Laws.

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PLAN OF DISTRIBUTION

We may sell securities described in this prospectus and any accompanying prospectus supplement through one or more underwriters for public offering and sale, and we also may sell securities to investors directly through the exercise of warrants or rights, or through one or more broker-dealers or agents.

We will prepare a prospectus supplement for each offering that will disclose the terms of the offering, including the name or names of any underwriters, dealers or agents, the purchase price of the securities and the proceeds to us from the sale, any underwriting discounts and other items constituting compensation to underwriters, dealers or agents.

We will fix a price or prices of our securities at:

•: market prices prevailing at the time of any sale under this registration statement;
•: prices related to market prices; or
•: negotiated prices.

We may change the price of the securities offered from time to time.

If we use underwriters or dealers in the sale, they will acquire the securities for their own account and they may resell these securities from time to time in one or more transactions (which may involve crosses and block transactions), including negotiated transactions, at a fixed public offering price or at varying prices determined at the time of sale. The securities may be offered to the public either through underwriting syndicates represented by one or more managing underwriters or directly by one or more of such firms. Unless otherwise disclosed in the prospectus supplement, the obligations of the underwriters to purchase securities will be subject to certain conditions precedent, and the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement if any are purchased. Any initial public offering price and any discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

If a prospectus supplement so indicates, the underwriters may, pursuant to Regulation M under the Securities Exchange Act of 1934, as amended, engage in transactions, including stabilization bids or the imposition of penalty bids, that may have the effect of stabilizing or maintaining the market price of the securities at a level above that which might otherwise prevail in the open market.

We may sell the securities directly or through agents designated by us from time to time, including in connection with a distribution to our security holders of rights to purchase such securities. We will name any agent involved in the offering and sale of the securities for which this prospectus is delivered, and disclose any commissions payable by us to the agent or the method by which the commissions can be determined, in the prospectus supplement. Unless otherwise indicated in the prospectus supplement, any agent will be acting on a best efforts basis for the period of its appointment.

We may agree to indemnify underwriters, dealers and agents who participate in the distribution of securities against certain liabilities to which they may become subject in connection with the sale of the securities, including liabilities arising under the Securities Act of 1933, as amended.

Certain of the underwriters, dealers and agents and their affiliates may be customers of, may engage in transactions with and may perform services for us or our affiliates in the ordinary course of business.

A prospectus and accompanying prospectus supplement in electronic form may be made available on the web sites maintained by the underwriters. The underwriters may agree to allocate a number of securities for sale to their online brokerage account holders. Such allocations of securities for internet

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distributions will be made on the same basis as other allocations. In addition, securities may be sold by the underwriters to securities dealers who resell securities to online brokerage account holders.

We may offer our units into an existing trading market on terms described in the prospectus supplement relating thereto. Underwriters and dealers who may participate in any at-the-market offerings will be described in the prospectus supplement relating thereto.

We may offer securities solicited directly by us and sell directly to institutional investors or offers, who may be deemed to be underwriters within the meaning of the Securities Act of 1933; as amended, with respect to any resale thereof. The terms of any such sales will be described in the prospectus supplement relating thereto.

Because FINRA views our common units as a direct participation program, any offering of common units under the registration statement, of which this prospectus forms a part, will be made in compliance with Rule 2310 of the FINRA Conduct Rules.

To the extent required, this prospectus may be amended or supplemented from time to time to describe a specific plan of distribution. The place and time of delivery for the securities in respect of which this prospectus is delivered will be set forth in the accompanying prospectus supplement.

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LEGAL MATTERS

Vinson & Elkins L.L.P., will pass upon the validity of the securities offered in this registration statement. If certain legal matters in connection with an offering of the securities made by this prospectus and a related prospectus supplement are passed on by counsel for the underwriters of such offering, that counsel will be named in the applicable prospectus supplement related to that offering.

EXPERTS

The consolidated financial statements of the Partnership as of December 31, 2011 and 2012, and for the years then ended, and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2012 have been incorporated by reference herein and in the registration statement in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

The 2010 consolidated financial statements (before the effects of the retrospective adjustments to the consolidated financial statement disclosures) (not separately presented herein) have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report incorporated by reference from the Partnership's Annual Report on Form 10-K for the year ended December 31, 2012 in this prospectus. The retrospective adjustments to the 2010 consolidated financial statements have been audited by KPMG LLP. The 2010 consolidated financial statements incorporated by reference in this prospectus have been so included in reliance upon the reports of Deloitte & Touche LLP and KPMG LLP, given upon their authority as experts in accounting and auditing.

The information incorporated by reference into this prospectus regarding estimated quantities of proved reserves and their present value is based on estimates of the proved reserves and present values of proved reserves as of December 31, 2012 prepared by Cawley, Gillespie & Associates, Inc., independent petroleum engineers. These estimates are incorporated by reference into this prospectus in reliance upon the authority of the firm as experts in these matters.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.

Set forth below are the expenses (other than underwriting discounts and commissions) expected to be incurred in connection with the issuance and distribution of the securities registered hereby. With the exception of the Securities and Exchange Commission registration fee, the amounts set forth below are estimates. We will pay all expenses (other than underwriting discounts and commissions) incurred by the offering unitholders.


Securities and Exchange Commission registration fee	$	37,179
Legal fees and expenses		50,000
Accounting fees and expenses		50,000
Printing expenses		15,000
Miscellaneous		47,821

Total	$	200,000

Item 15. Indemnification of Directors and Officers.

Eagle Rock Energy Partners, L.P.

Section 17-108 of the Delaware Revised Uniform Limited Partnership Act empowers a Delaware limited partnership to indemnify and hold harmless any partner or other persons from and against all claims and demands whatsoever. Under Eagle Rock Energy Partners, L.P.'s limited partnership agreement and subject to specified limitations, Eagle Rock Energy Partners, L.P. shall indemnify to the fullest extent permitted by Delaware law any person serving as a director, officer, member, partner, fiduciary or trustee of Eagle Rock Energy Partners, L.P. or any of its affiliates or any person serving in such capacity for any other entity at the request of Eagle Rock Energy Partners, L.P. or any of its affiliates from and against all losses, claims, damages or similar events arising by reason of such person's above mentioned position with respect to Eagle Rock Energy Partners, L.P. Provided, that such person shall not be indemnified and held harmless if there has been a final and non-appealable judgment entered by a court determining that such person acted in bad faith. Additionally, Eagle Rock Energy Partners, L.P. will indemnify to the fullest extent permitted by law, from and against all losses, claims, damages or similar events any person designated by Eagle Rock Energy Partners, L.P.'s general partner. Any indemnification under Eagle Rock Energy Partners, L.P.'s limited partnership agreement will only be out of its assets. Eagle Rock Energy Partners, L.P. is authorized to purchase insurance against liabilities asserted against and expenses incurred by persons from Eagle Rock Energy Partners, L.P.'s activities, regardless of whether Eagle Rock Energy Partners, L.P. would have the power to indemnify the person against liabilities under Eagle Rock Energy Partners, L.P.'s limited partnership agreement.

Each of the nine directors and the six senior vice presidents of G&P (collectively, the "Indemnitees") and Eagle Rock Energy Partners, L.P., G&P, Eagle Rock Energy GP, L.P. (all three entities collectively, "the Indemnitors") have entered into a Supplemental Indemnification Agreement. The agreement provides for indemnification coverage if a person (a) serving Eagle Rock Energy Partners, L.P. or any of its subsidiaries, or (b) serving at the request of Eagle Rock Energy Partners, L.P. or any of its subsidiaries, becomes involved in litigation proceedings. The Indemnitee may request advancement of expenses upon delivery of an undertaking to G&P that the Indemnitee will reimburse G&P for the expenses if it is determined that the Indemnitee is not entitled to the expenses. The Indemnitee also may request that independent counsel determine whether the Indemnitee is entitled to indemnification. If not requested, the disinterested board of directors members will make

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the determination of entitlement, or the board of directors will appoint independent counsel. The Indemnitee is entitled to indemnification to the fullest extent of the applicable Delaware law unless the Indemnitee's conduct was knowingly fraudulent, not in good faith or constituted willful misconduct, or, in the case of a criminal matter, was knowingly unlawful or was otherwise covered by insurance payments. Although the indemnification obligations of Eagle Rock Energy Partners, L.P. under the Supplemental Indemnification Agreements are intended to be supplemental to the indemnification provided under Eagle Rock Energy Partners, L.P.'s partnership agreement as discussed above, the general indemnification standard is substantively no different than that provided under that partnership agreement.

Eagle Rock Energy Finance Corp.

Section 145 of the General Corporation Law of the State of Delaware, among other things, empowers a Delaware corporation to indemnify any person who was or is a party or is threatened to be made a party to any threatened, pending, or completed action, suit, or proceeding (other than an action by or in the right of the corporation) by reason of the fact that such person is or was a director, officer, employee, or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee, or agent of another corporation or other enterprise, against expenses (including attorneys' fees), judgments, fines, and amounts paid in settlement actually and reasonably incurred by him in connection with such action, suit, or proceeding if he acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, with respect to any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful. Similar indemnity is authorized for such persons against expenses (including attorneys' fees) actually and reasonably incurred by such persons in connection with the defense or settlement of any such threatened, pending, or completed action or suit if such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and provided further that (unless a court of competent jurisdiction otherwise provides) such person shall not have been adjudged liable to the corporation. Any such indemnification may be made only as authorized in each specific case upon a determination by the stockholders or disinterested directors or by independent legal counsel in a written opinion that indemnification is proper because the indemnitee has met the applicable standard of conduct.

Section 145 further authorizes a corporation to purchase and maintain insurance on behalf of any person who is or was a director, officer, employee, or agent of the corporation, or is or was serving at the request of the corporation as a director, officer, employee, or agent of another corporation or enterprise, if any, as the corporation deems appropriate.

The bylaws of Eagle Rock Energy Finance Corp. provide for indemnification obligations substantially similar to those otherwise provided by Section 145.

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Item 16. Exhibits.

Exhibit Number			Description

	**1.1		Form of Underwriting Agreement
	2.1		Purchase and Sale Agreement by and between BP America Production Company and Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 1.1 of the registrant's Current Report on Form 8-K filed on August 10, 2012).
	2.2		Membership Interest Contribution Agreement, by and among (i) CC Energy II L.L.C., Crow Creek Energy II L.L.C. and Crow Creek Operating Company II L.L.C., (ii) Natural Gas Partners VIII, L.P. and the other contributors party thereto and (iii) Eagle Rock Energy Partners, L.P., dated as of April 12, 2011 (incorporated by reference to Exhibit 2.1 to the Partnership's Current Report on From 8-K filed on April 13, 2011).
	3.1		Certificate of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 3.1 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.2		Second Amended and Restated Agreement of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 3.1 of the registrant's current report on Form 8-K filed with the Commission on May 25, 2010).
	3.3		Amendment No. 1 to the Second Amended and Restated Agreement of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 4.1 of the registrant's current report on Form 8-K filed with the Commission on July 30, 2010).
	3.4		Certificate of Limited Partnership of Eagle Rock Energy GP, L.P. (incorporated by reference to Exhibit 3.3 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.5		Limited Partnership Agreement of Eagle Rock Energy GP, L.P. (incorporated by reference to Exhibit 3.4 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.6		Certificate of Formation of Eagle Rock Energy G&P, LLC (incorporated by reference to Exhibit 3.5 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.7		Third Amended and Restated Limited Liability Company Agreement of Eagle Rock Energy G&P, LLC (incorporated by reference to Exhibit 42 of the registrant's current report on Form 8-K filed with the Commission on July 30, 2010).
	*4.1		Form of Indenture for Debt Securities.
	*4.2		Form of Debt Securities (included in Exhibit 4.1).
	4.3		Indenture dated as of May 27, 2011 among Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.1 to Eagle Rock Energy Partners, L.P.'s Current Report on Form 8-K filed on May 27, 2011).
	4.4		First Supplemental Indenture dated as of June 28, 2011, among Eagle Rock Gas Services, LLC, a subsidiary of Eagle Rock Energy Partners, L.P., Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.3 to Eagle Rock Energy Partners, L.P.'s Quarterly Report on Form 10-Q filed on August 4, 2011).

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Exhibit Number			Description

	4.5		Second Supplemental Indenture dated as of November 19, 2012, among Eagle Rock Crude Pipelines, LLC, a subsidiary of Eagle Rock Energy Partners, L.P., Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.4 to Eagle Rock Energy Partners, L.P.'s Exchange Offer on Form S-4 filed on November 20, 2012).
	4.6		Form of Common Unit Certificate (included as Exhibit A to the Second Partnership Agreement of Eagle Rock Energy Partners, L.P.) (incorporated by reference to Exhibit 3.1 of the registrant's current report on Form 8-K filed on May 25, 2010).
	*5.1		Opinion of Vinson & Elkins L.L.P. as to the legality of the securities being registered.
	*8.1		Opinion of Vinson & Elkins L.L.P. as to tax matters.
	*12.1		Statement of Computation of Ratio of Earnings to Fixed Charges.
	*23.1		Consent of KPMG LLP.
	*23.2		Consent of Deloitte & Touche LLP.
	*23.3		Consent of Cawley, Gillespie & Associates, Inc.
	*23.4		Consent of Vinson & Elkins L.L.P. (contained in Exhibits 5.1 and 8.1).
	*24.1		Power of Attorney (included on signature page of this registration statement).
	***25.1		Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 under the Senior Indenture.

*: Filed herewith
**: To be filed as an Exhibit to a Current Report on Form 8-K or a post-effective amendment to this registration statement.
***: To be filed in accordance with Section 310(a) of the Trust Indenture Act of 1939, as amended.

Item 17. Undertakings.

The undersigned registrant hereby undertakes:

(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

(ii) To reflect in the prospectus any facts or events arising after the effective date of this registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in this registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of a prospectus filed with the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent of the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement; and

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(iii) To include any material information with respect to the plan of distribution not previously disclosed in this registration statement or any material change to such information in this registration statement;

provided, however, that paragraphs (1)(i) and (1)(ii) above do not apply if the registration statement is on Form S-3 and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the SEC by the registrants pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement;

(2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

(4) That, for the purpose of determining liability under the Securities Act to any purchaser:

(a) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(b) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(1)(i), (vii), or (x) for the purpose of providing the information required by section 10(a) of the Securities Act shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. Provided, however, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date.

(5) That, for the purpose of determining liability of the registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(a) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(b) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

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(c) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(d) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser.

Each undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in this registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers and controlling persons of the registrant pursuant to the foregoing provisions, or otherwise, the registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act of 1933 and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue.

The undersigned registrant hereby undertakes to file an application for the purpose of determining the eligibility of the Trustee to act under subsection (a) of Section 310 of the Trust Indenture Act of 1939, as amended (the "Act") in accordance with the rules and regulations prescribed by the SEC under Section 305(b)(2) of the Act.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filings on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Houston, Texas on March 26, 2013.


		EAGLE ROCK ENERGY PARTNERS, L.P.
		By:		Eagle Rock Energy GP, L.P., its general partner
		By:		Eagle Rock Energy G&P, LLC, its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chairman and Chief Executive Officer
		EAGLE ROCK ENERGY FINANCE CORP.
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		EAGLE ROCK ENERGY G&P, LLC
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chairman and Chief Executive Officer
		EAGLE ROCK ENERGY GP, L.P.
		By:		Eagle Rock Energy G&P, LLC, its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chairman and Chief Executive Officer

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		EROC PRODUCTION, LLC
		By:		Eagle Rock Energy Partners, L.P., its sole member
		By:		Eagle Rock Energy GP, L.P., its general partner
		By:		Eagle Rock Energy G&P, LLC, its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chairman and Chief Executive Officer
		CMA PIPELINE PARTNERSHIP, LLC EAGLE ROCK GAS SERVICES, LLC EAGLE ROCK MARKETING, LLC EAGLE ROCK MID-CONTINENT HOLDING, LLC EAGLE ROCK PIPELINE GP, LLC ESCAMBIA ASSET CO. LLC ESCAMBIA OPERATING CO. LLC GALVESTON BAY GATHERING, LLC SUPERIOR GAS COMPRESSION, LLC
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		EAGLE ROCK MID-CONTINENT ASSET, LLC EAGLE ROCK MID-CONTINENT OPERATING, LLC
		By:		Eagle Rock Mid-Continent Holding, LLC, their sole member
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer

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		EAGLE ROCK DESOTO PIPELINE, L.P. EAGLE ROCK ENERGY SERVICES, L.P. EAGLE ROCK FIELD SERVICES, L.P. EAGLE ROCK GAS GATHERING & PROCESSING, LTD. EAGLE ROCK GOM, L.P. EAGLE ROCK MIDSTREAM, L.P. EAGLE ROCK OPERATING, L.P. EAGLE ROCK PIPELINE, L.P. EROC GATHERING COMPANY, LP EROC MIDSTREAM ENERGY, L.P. EROC QUITMAN GATHERING CO., LP MIDSTREAM GAS SERVICES, L.P.
		By:		Eagle Rock Pipeline GP, LLC, their general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		EAGLE ROCK UPSTREAM DEVELOPMENT II, L.P.
		By:		EROC Production, LLC, its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		HESCO GATHERING COMPANY, LLC HESCO PIPELINE COMPANY, L.L.C.
		By:		EROC Midstream Energy, L.P., their sole member
		By:		Eagle Rock Pipeline GP, LLC, its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer

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		EAGLE ROCK ENERGY ACQUISITION CO., INC. EAGLE ROCK ENERGY ACQUISITION CO. II, INC. EAGLE ROCK ENERGY G&P HOLDING, INC. EAGLE ROCK UPSTREAM DEVELOPMENT COMPANY, INC. EAGLE ROCK UPSTREAM DEVELOPMENT COMPANY II, INC.
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		EAGLE ROCK ACQUISITION PARTNERSHIP, L.P.
		By:		Eagle Rock Upstream Development Company, Inc., its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer
		EAGLE ROCK ACQUISITION PARTNERSHIP II, L.P.
		By:		Eagle Rock Upstream Development Company II, Inc., its general partner
		By:		/s/ JOSEPH A. MILLS Joseph A. Mills Chief Executive Officer

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POWER OF ATTORNEY

All those persons whose signatures appear below do hereby constitute and appoint Joseph A. Mills, Jeffrey P. Wood and Charles C. Boettcher, and each of them, our true and lawful attorney-in-fact and agent, to do any and all acts and things in our names and on our behalf in our capacities as directors and officers and to execute any and all instruments for us and in our name in the capacities indicated below, which said attorney and agent may deem necessary or advisable to enable said registrant to comply with the Securities Act of 1933 and any rules, regulations and requirements of the Securities and Exchange Commission, in connection with the registration statements, or any registration statement for this offering that is to be effective upon filing pursuant to Rule 462 under the Securities Act of 1933, including specifically, but without limitation, power and authority to sign for us or any of us in our names in the capacities indicated below, any and all amendments (including post-effective amendments) hereof; and we do hereby ratify and confirm all that said attorneys and agents shall do or cause to be done by virtue thereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed below by the following persons in the capacities and the dates indicated.

EAGLE ROCK ENERGY G&P, LLC, on behalf of itself and as the general partner of EAGLE ROCK ENERGY GP, L.P., on behalf of itself and as the general partner of EAGLE ROCK ENERGY PARTNERS, L.P., on behalf of itself and as the sole member of EROC PRODUCTION, LLC, on behalf of itself and as the general partner of EAGLE ROCK UPSTREAM DEVELOPMENT II, L.P.

Signature	Title	Date


/s/ JOSEPH A. MILLS Joseph A. Mills	Director, Chief Executive Officer (Principal Executive Officer)	March 26, 2013
/s/ JEFFREY P. WOOD Jeffrey P. Wood	Senior Vice President, Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)	March 26, 2013
/s/ DAVID W. HAYES David W. Hayes	Director	March 26, 2013
/s/ WILLIAM J. QUINN William J. Quinn	Director	March 26, 2013
/s/ PHILIP B. SMITH Philip B. Smith	Director	March 26, 2013
/s/ WILLIAM A. SMITH William A. Smith	Director	March 26, 2013

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Signature	Title	Date


/s/ CHRISTOPHER D. RAY Christopher D. Ray	Director	March 26, 2013
/s/ WILLIAM K. WHITE William K. White	Director	March 26, 2013
/s/ PEGGY A. HEEG Peggy A. Heeg	Director	March 26, 2013
/s/ HERBERT C. WILLIAMSON, III Herbert C. Williamson, III	Director	March 26, 2013

EAGLE ROCK ENERGY FINANCE CORP.

Signature	Title	Date


/s/ JOSEPH A. MILLS Joseph A. Mills	Director, Chief Executive Officer (Principal Executive Officer)	March 26, 2013
/s/ JEFFREY P. WOOD Jeffrey P. Wood	Director, Senior Vice President, Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)	March 26, 2013
/s/ CHARLES C. BOETTCHER Charles C. Boettcher	Director, Senior Vice President, General Counsel, Chief Compliance Officer and Secretary	March 26, 2013

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CMA PIPELINE PARTNERSHIP, LLC, EAGLE ROCK GAS SERVICES, LLC, EAGLE ROCK MARKETING, LLC, ESCAMBIA ASSET CO. LLC, ESCAMBIA OPERATING CO. LLC, GALVESTON BAY GATHERING, LLC and SUPERIOR GAS COMPRESSION, LLC

and

EAGLE ROCK MID-CONTINENT HOLDING, LLC, on behalf of itself and as the sole member of each of EAGLE ROCK MID-CONTINENT ASSET, LLC and EAGLE ROCK MID-CONTINENT OPERATING, LLC

and

EAGLE ROCK PIPELINE GP, LLC, on behalf of itself and as the general partner of EAGLE ROCK DESOTO PIPELINE, L.P., EAGLE ROCK ENERGY SERVICES, L.P., EAGLE ROCK FIELD SERVICES, L.P., EAGLE ROCK GAS GATHERING & PROCESSING, LTD., EAGLE ROCK GOM, L.P., EAGLE ROCK OPERATING, L.P., EAGLE ROCK PIPELINE, L.P., EROC GATHERING COMPANY, LP, EROC MIDSTREAM ENERGY, L.P., EROC QUITMAN GATHERING CO., LP, MIDSTREAM GAS SERVICES, L.P. and EAGLE ROCK MIDSTREAM, L.P., on behalf of itself and as the sole member of each of HESCO GATHERING COMPANY, LLC and HESCO PIPELINE COMPANY, LLC

Signature	Title	Date


/s/ JOSEPH A. MILLS Joseph A. Mills	Manager, Chief Executive Officer (Principal Executive Officer)	March 26, 2013
/s/ JEFFREY P. WOOD Jeffrey P. Wood	Manager, Senior Vice President, Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)	March 26, 2013
/s/ CHARLES C. BOETTCHER Charles C. Boettcher	Manager, Senior Vice President, General Counsel, Chief Compliance Officer and Secretary	March 26, 2013

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EAGLE ROCK ENERGY ACQUISITION CO., INC., EAGLE ROCK ENERGY ACQUISITION CO. II, INC., EAGLE ROCK ENERGY G&P HOLDING, INC.

and

EAGLE ROCK UPSTREAM DEVELOPMENT COMPANY, INC., on behalf of itself and as the general partner of EAGLE ROCK ACQUISITION PARTNERSHIP, L.P.

and

EAGLE ROCK UPSTREAM DEVELOPMENT COMPANY II, INC., on behalf of itself and as the general partner of EAGLE ROCK ACQUISITION PARTNERSHIP II, L.P.

Signature	Title	Date


/s/ JOSEPH A. MILLS Joseph A. Mills	Director, Chief Executive Officer (Principal Executive Officer)	March 26, 2013
/s/ JEFFREY P. WOOD Jeffrey P. Wood	Director, Senior Vice President, Chief Financial Officer and Treasurer (Principal Financial and Accounting Officer)	March 26, 2013
/s/ CHARLES C. BOETTCHER Charles C. Boettcher	Director, Senior Vice President, General Counsel, Chief Compliance Officer and Secretary	March 26, 2013

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INDEX TO EXHIBITS

Exhibit Number			Description

	**1.1		Form of Underwriting Agreement
	2.1		Purchase and Sale Agreement by and between BP America Production Company and Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 1.1 of the registrant's Current Report on Form 8-K filed on August 10, 2012).
	2.2		Membership Interest Contribution Agreement, by and among (i) CC Energy II L.L.C., Crow Creek Energy II L.L.C. and Crow Creek Operating Company II L.L.C., (ii) Natural Gas Partners VIII, L.P. and the other contributors party thereto and (iii) Eagle Rock Energy Partners, L.P., dated as of April 12, 2011 (incorporated by reference to Exhibit 2.1 to the Partnership's Current Report on From 8-K filed on April 13, 2011).
	3.1		Certificate of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 3.1 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.2		Second Amended and Restated Agreement of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 3.1 of the registrant's current report on Form 8-K filed with the Commission on May 25, 2010).
	3.3		Amendment No. 1 to the Second Amended and Restated Agreement of Limited Partnership of Eagle Rock Energy Partners, L.P. (incorporated by reference to Exhibit 4.1 of the registrant's current report on Form 8-K filed with the Commission on July 30, 2010).
	3.4		Certificate of Limited Partnership of Eagle Rock Energy GP, L.P. (incorporated by reference to Exhibit 3.3 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.5		Limited Partnership Agreement of Eagle Rock Energy GP, L.P. (incorporated by reference to Exhibit 3.4 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.6		Certificate of Formation of Eagle Rock Energy G&P, LLC (incorporated by reference to Exhibit 3.5 of the registrant's registration statement on Form S-1 (File No. 333-134750).
	3.7		Third Amended and Restated Limited Liability Company Agreement of Eagle Rock Energy G&P, LLC (incorporated by reference to Exhibit 42 of the registrant's current report on Form 8-K filed with the Commission on July 30, 2010).
	*4.1		Form of Indenture for Debt Securities.
	*4.2		Form of Debt Securities (included in Exhibit 4.1).
	4.3		Indenture dated as of May 27, 2011 among Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.1 to Eagle Rock Energy Partners, L.P.'s Current Report on Form 8-K filed on May 27, 2011).
	4.4		First Supplemental Indenture dated as of June 28, 2011, among Eagle Rock Gas Services, LLC, a subsidiary of Eagle Rock Energy Partners, L.P., Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.3 to Eagle Rock Energy Partners, L.P.'s Quarterly Report on Form 10-Q filed on August 4, 2011).

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Exhibit Number			Description

	4.5		Second Supplemental Indenture dated as of November 19, 2012, among Eagle Rock Crude Pipelines, LLC, a subsidiary of Eagle Rock Energy Partners, L.P., Eagle Rock Energy Partners, L.P., Eagle Rock Energy Finance Corp., the Guarantors named therein and U.S. Bank National Association, as trustee (incorporated by reference to Exhibit 4.4 to Eagle Rock Energy Partners, L.P.'s Exchange Offer on Form S-4 filed on November 20, 2012).
	4.6		Form of Common Unit Certificate (included as Exhibit A to the Second Partnership Agreement of Eagle Rock Energy Partners, L.P.) (incorporated by reference to Exhibit 3.1 of the registrant's current report on Form 8-K filed on May 25, 2010).
	*5.1		Opinion of Vinson & Elkins L.L.P. as to the legality of the securities being registered.
	*8.1		Opinion of Vinson & Elkins L.L.P. as to tax matters.
	*12.1		Statement of Computation of Ratio of Earnings to Fixed Charges.
	*23.1		Consent of KPMG LLP.
	*23.2		Consent of Deloitte & Touche LLP.
	*23.3		Consent of Cawley, Gillespie & Associates, Inc.
	*23.4		Consent of Vinson & Elkins L.L.P. (contained in Exhibits 5.1 and 8.1).
	*24.1		Power of Attorney (included on signature page of this registration statement).
	***25.1		Form T-1 Statement of Eligibility and Qualification under the Trust Indenture Act of 1939 under the Senior Indenture.

*: Filed herewith
**: To be filed as an Exhibit to a Current Report on Form 8-K or a post-effective amendment to this registration statement.
***: To be filed in accordance with Section 310(a) of the Trust Indenture Act of 1939, as amended.

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Eagle Rock Energy G&P Inactive S-3Shelf registration