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Our sole revenue generating asset is our 10.6%18.3% limited partner interest in OpCo. We also own the general partner interest of OpCo. OpCo owns:

As the owner of the general partner interest of OpCo, we control all aspects of the management of OpCo, including its cash distribution policy. See "—OpCo's Assets."

The following table provides information regarding OpCo's ethylene production facilities as of December 31, 2014:2017:

Two of OpCo's ethylene production facilities, which we refer to as Petro 1 and Petro 2 and, collectively, as Lake Charles Olefins, are located at Westlake's Lake Charles site. The combined capacity of OpCo'sthese two ethylene production facilities is approximately 2.73.0 billion pounds per year. In the first quarter of 2013, we completed the expansion of Petro 2 to increase the ethane-based ethylene capacity at the Lake Charles facility and its conversion to 100% ethane feedstock capability. The Petro 2 expansion increased ethane-based ethylene capacity by approximately 240 million pounds annually.

Within Westlake's Lake Charles site, Petro 1 and Petro 2 are connected by pipeline systems to Westlake's PEpolyethylene plants. Westlake may use the ethylene it purchases from OpCo at its Lake Charles facility or transfer it to its Geismar facility or its Longview facility, either through physical transportation or via exchange transactions. Westlake may also use the ethylene it purchases from OpCo with chlorine to produce ethylene dichloride and transport it via barge to Westlake's Calvert City site.

In addition, OpCo produces ethylene co-products including chemical grade propylene, crude butadiene, pyrolysis gasoline and hydrogen. OpCo sells its output of these co-products to external customers.

One of OpCo's ethylene production facilities is located at Westlake's Calvert City site, which we refer to as Calvert City Olefins. The capacity of Calvert City Olefins is 630approximately 730 million pounds per year. Our recently completed project at Calvert City Olefins converted its feedstock from propane to ethane and increased its ethylene capacity by approximately 180 million pounds annually. This conversion enables OpCo to access low-cost ethane produced from the Marcellus Shale versus higher cost propane historically utilized by Calvert City Olefins as a feedstock.

OpCo owns a 200-mile 10-inch diameter ethylene pipeline system that connects the Equistar Pipeline, the Flint Hills Pipeline and the Lone Star Storage Facility in Mont Belvieu to the Longview, Texas chemical site, which includes Westlake's Longview PE production facility. The system has a capacity of 3.5 million pounds per day of ethylene and is operated as a common carrier pipeline by Buckeye Development & Logistics I LLC. As a common carrier intrastate pipeline in Texas, the

system is subject to rate regulation under the Texas Utilities Code, as implemented by the Texas Railroad Commission, or the TRRC, and has a tariff on file with the TRRC.

OpCo has perpetual and paid-up licenses for steam cracking and process recovery technology used at its ethylene plants.

TheExcept as otherwise indicated, the agreements described below became effective on August 4, 2014, concurrent with the closing of the IPO.

OpCo and Westlake entered into the Ethylene Sales Agreement, which has an initial term through December 31, 2026 and automatic 12-month renewal periods until terminated at the end of the initial term or any renewal term on 12-months' notice. The Ethylene Sales Agreement requires Westlake to purchase OpCo's planned ethylene production each year, subject to certain exceptions and a maximum commitment of 3.8 billion pounds per year, less product sold by OpCo to third parties equal to approximately 5% of the annual output. If OpCo's actual production is in excess of planned ethylene production, Westlake has the option to purchase up to 95% of production in excess of planned production. Westlake's purchase price for ethylene under the Ethylene Sales Agreement includes a $0.10 per pound margin, the total costs incurred by OpCo for the feedstock and natural gas to produce each pound of ethylene (subject to a usage cap and a floor), and estimated operating costs, maintenance capital expenditures and other turnaround expenditures, less net proceeds from co-products sales. Under specified circumstances, cost underrecoveries may be carried forwardThis purchase price is not designed to cover capital expenditures for recovery in subsequent years.expansion. Variable costs not incurred by OpCo due to a deficiency in takes are rebated to Westlake. Under specified circumstances, unrecovered costs may be carried forward for recovery in subsequent years.

OpCo and Westlake entered into the Feedstock Supply Agreement, which has an initial term through December 31, 2026 and automatic 12-month renewal periods until terminated at the end of the initial term or any renewal term on 12-months' notice. Under the Feedstock Supply Agreement, Westlake agrees to sell OpCo ethane and other feedstock in amounts sufficient for OpCo to produce the ethylene to be sold under the Ethylene Sales Agreement. The price at which ethane and feedstock is sold includes an indexed price for spot gas liquids at Mont Belvieu and applicable transportation, storage and other costs.

OpCo and Westlake entered into the servicesServices and secondment agreement,Secondment Agreement, pursuant to which OpCo will provide Westlake with various utilities and utility services and in exchange for Westlake providing OpCo with various utility services, comprehensive operating services for OpCo's units, services for the maintenance and operation of the common facilities and seconded employees to perform all services required under the agreement.

OpCo and Westlake entered into two 50-year site lease agreements (the "Site Leases"). Under the Site Leases, OpCo leases the real property underlying Calvert City Olefins and Lake Charles Olefins and is granted certain use and access right related thereto, for a base rental amount of $1 per year per site. Each of the Site Leases is terminable by the lessor upon the occurrence of certain events of default or by OpCo if Calvert City Olefins or Lake Charles Olefins, as applicable, is destroyed by casualty. Pursuant to the Site Leases, the lessor has the right to restore and repurchase the units for fair market value if OpCo fails to expeditiously restore Calvert City Olefins or Lake Charles Olefins, as applicable, following a casualty loss. Subject to

We, OpCo GP and Westlake entered into an agreement of limited partnership for OpCo (the "OpCo LP Agreement"). The OpCo LP Agreement governs the ownership and management of OpCo and designates OpCo GP as the general partner of OpCo. OpCo GP generally has complete authority to manage OpCo's business and affairs. We control OpCo GP, as its sole member, subject to certain approval rights held by Westlake.

On August 1, 2017, the Partnership, OpCo and Other RegulationsWestlake executed an Investment Management Agreement that authorized Westlake to invest the Partnership and OpCo’s excess cash with Westlake for a term of up to a maximum of nine months. Per the terms of the Investment Management Agreement, the Partnership earns a market return plus five basis points and Westlake provides daily availability of the invested cash to meet any liquidity needs of the Partnership or OpCo.

As is common in our industry, producing ethylene involves the use, storage, transportationwe and disposal of large quantities of toxic and hazardous materials, and our manufacturing operations require the generation and disposal of large quantities of hazardous wastes. We are subject to extensive, evolving and increasingly stringent federal, state and local environmental laws and regulations, which address, among other things, the following:

EPA Region 4 has identified concerns with the facility’s compliance under the Risk Management Program and Release Prevention regulations in connection with certain emissions release events between 2011 and 2015. Westlake has not agreed that any flares are outengaged in communications with EPA Region 4 to resolve these concerns. The Partnership believes the resolution of compliance or that any corrective actions are warranted. Depending onthese matters may require the outcomepayment of Westlake's negotiations with the EPA, additional controls on emissions from our flares may be required and these could resulta monetary sanction in increased capital and operating costs. Westlake will indemnify us for liabilities that occurred or existed prior to August 4, 2014.excess of $100,000.

In addition to the extent that it covers our assets, Westlake will indemnify us for liabilitiesmatters described above, the Partnership is involved in various legal proceedings incidental to the extent such liabilities occurred or existed prior to August 4, 2014.

Also, see the discussion of our environmental matters contained in Item 1A. "Risk Factors" and remedial actions to comply with existing laws governing environmental protection will not have a material adverse effect on our business and financial results.Item 3"—Legal Proceedings" below.

Neither we nor OpCo has any employees. Under the servicesServices and secondment agreementSecondment Agreement with Westlake, Westlake seconds employees to OpCo to allow OpCo to operate its facilities. Such seconded employees are under OpCo's control while they work on OpCo's facilities. As of December 31, 2014, 1452017, 119 employees were seconded to OpCo. Of these, 21 are covered by collective bargaining agreements that expire on November 1, 2019. There have been no strikes or lockouts, and neither OpCo nor Westlake has experienced any work stoppages throughout its history. We believe that Westlake's relationship with the local union officials and bargaining committees is open and positive.

In the ordinary conduct of our business, we and Westlake and our and Westlake's subsidiaries, including OpCo, are subject to periodic lawsuits, investigations and claims, including environmental claims and employee related matters. Although we cannot predict with certainty the ultimate resolution of lawsuits, investigations and claims asserted against us, we do not believe that any currently pending legal proceeding or proceedings to which we or Westlake or any of our or Westlake's subsidiaries, including OpCo, are a party will have a material adverse effect on our business, results of operations, cash flows or financial condition.

Due to the Ethylene Sales Agreement and integration with Westlake, OpCo does not directly compete with other ethylene producers for 95% of the planned volumes it produces. It is only on the 5% of planned ethylene volumes not sold to Westlake where OpCo competes with other regional merchant ethylene producers, including LyondellBasell Industries, N.V., Royal Dutch Shell, Williams Companies, BASF Corporation and Flint Hills Resources.

Item 1A. Risk Factors

Limited partner interests are inherently different from the capital stock of a corporation, although many of the business risks to which we are subject are similar to those that would be faced by a corporation engaged in a similar business. Security

holders and potential investors should carefully consider the following risk factors together with all of the other information included in this report. If any of the following risks were actually to occur, our business, financial condition, results of operations or cash flows could be materially adversely affected.

Currently, all of our cash flow is generated from cash distributions from OpCo, and a substantial majority of OpCo's cash flow is generated from payments by Westlake under the Ethylene Sales Agreement. Westlake's obligations to purchase ethylene under the Ethylene Sales Agreement may be temporarily suspended to the extent OpCo is unable to perform its obligations caused by any of certain events outside the reasonable control of OpCo. Such events include, for example, acts of God or calamities which affect the operation of OpCo's facilities; certain labor difficulties (whether or not the demands of the employees are within the power of OpCo to concede); and governmental orders or laws. In addition, Westlake is not obligated to purchase ethylene with respect to any period during which OpCo's facilities are not operating due to scheduled or unscheduled maintenance or turnarounds (which occur approximately every five years) other than under certain circumstances relating to the occurrence of force majeure. We expect that each of OpCo's facilities will have a turnaround once every five years and will not operate for typically between 25 and 45 days during each turnaround by itself. However, the duration of a turnaround by itself may be longer than expected or may cost more than originally estimated. Furthermore, expansions may also coincide with turnarounds, which may complicate and delay the completion of such turnarounds. For example, the expansion of Petro 1, as described in "Item 1. Business—OpCo's Assets—Lake Charles Olefins," is being completed in conjunction with a planned turnaround, which is expected to result in a downtime of between 75 and 80 days. A suspension of Westlake's obligations under the Ethylene Sales Agreement, including during periods where OpCo's facilities are not operating

Westlake may be unable to generate enough cash flow from operations to meet its minimum obligations under the Ethylene Sales Agreement if its business is adversely impacted by competition, operational problems, general adverse economic conditions or the inability to obtain feedstock. For example, sustained lower prices of crude oil, such as the prices experienced insince the second halfthird quarter of 2014 and continuing through 2017 (as of December 31, 2017, approximately 44% lower than their 2014 peak levels) may lead to lower margins for Westlake in the United States. If Westlake were unable to meet its minimum payment obligations to OpCo as a result of any one or more of these factors, our ability to make distributions to our unitholders would be reduced or eliminated. The level of payments made by Westlake will depend upon its ability to pay its minimum obligations under the Ethylene Sales Agreement and its ability and election to increase volumes above the minimums specified in the Ethylene Sales Agreement, which in turn are dependent upon, among other things, the level of production at Westlake's other facilities. If Westlake is unable to generate sufficient cash flow from its operations to meet its obligations, or otherwise defaults on its obligations, under the Ethylene Sales Agreement, OpCo will not have sufficient available cash to distribute to us to enable us to pay the minimum quarterly distribution, which will fluctuate from quarter to quarter based on the following factors, some of which are beyond our control:

Our ability to make distributions to unitholders is substantially dependent on Westlake's ability to meet its minimum contractual obligations under the Ethylene Sales Agreement. If Westlake defaults on its obligations, our ability to make distributions to our unitholders would be reduced or eliminated. Westlake has not pledged any assets to us as security for the performance of its obligations.

Westlake has not agreed with us to limit its ability to incur indebtedness, pledge or sell assets or make investments, and we have no control over the amount of indebtedness Westlake incurs, the assets it pledges or sells or the investments it makes.

All of our cash is currently generated from cash distributions from OpCo. Westlake's credit facility and the indentures governing its senior notes impose significant operating and financial restrictions on OpCo. These restrictions limit OpCo's ability to:

In addition, the indentures governing Westlake's senior notes prevent OpCo from making distributions to us if any default or event of default (as defined in the indentures) exists.

These limitations are subject to a number of important qualifications and exceptions. However, the effectiveness of many of these restrictions in the indentures governing Westlake's senior notes is currently suspended under the indentures because the senior notes are currently rated investment grade by at least two nationally recognized credit rating agencies.

These covenants may adversely affect OpCo's ability to finance future business opportunities. A breach of any of these covenants could result in a default in respect of the related debt. If a default occurred, the relevant lenders could elect to declare the debt, together with accrued interest and other fees, to be immediately due and payable and proceed against any collateral securing that debt, including OpCo and its assets. In addition, any acceleration of debt under Westlake's credit facility will constitute a default under some of Westlake's other debt, including the indentures governing its senior notes each of which OpCo has guaranteed.

OpCo's operations are subject to significant hazards and risks inherent in ethylene production operations. These hazards and risks include, but are not limited to, equipment malfunction, explosions, fires and the effects of severe weather conditions, any of which could result in production and transportation difficulties and disruptions, pollution, personal injury or wrongful death claims and other damage to our properties and the property of others. There is also risk of mechanical failure of OpCo's facilities both in the normal course of operations and following unforeseen events. Any adverse developments at any of OpCo's facilities could have a material adverse effect on our results of operations and therefore our ability to distribute cash to unitholders.

Because substantially all of OpCo's sales are generated at three facilities located at two sites, any such events at any facility or site could significantly disrupt OpCo's ethylene production and its ability to supply ethylene to its customers. Any sustained disruption in its ability to meet its supply obligations under the Ethylene Sales Agreement could have a material adverse effect on our results of operations and therefore our ability to distribute cash to unitholders.

The purchase price under the Ethylene Sales Agreement will beis based on OpCo's actual ethane, other feedstock and natural gas costs and an annual estimate of other operating costs and maintenance capital expenditures and other turnaround expenditures. The price is designed to permit OpCo to recover the portion of its costs of feedstocks and other costs to operate the ethylene production facilities associated with the percentage of its production capacity purchased by Westlake and generate a fixed margin per pound of ethylene purchased by Westlake. The price is not designed to allow OpCo to recover any capital expenditures related to expansion (such as our plans to upgrade and expand the capacity of Petro 1 and our facility in Calvert City), or operational efficiency. The ethylene sales price willalso does not increase to cover our public partnership costs. Both of these costs which will reduce our net operating profit.

The Ethylene Sales Agreement sets a $0.10 per pound margin for a substantial majority of OpCo's ethylene production, limiting OpCo's ability to take advantage of potential decreased ethane and other feedstock prices, potential increased ethylene prices or other favorable market developments. Under these circumstances, OpCo may not be in a position to enable its partners, including us, to benefit from favorable market developments (including any potential ethylene price increase in the future) through increased distributions. In addition, under these circumstances, OpCo may be disadvantaged relative to those of its competitors that are in a better position to take advantage of favorable market developments.

Westlake's obligations under the Ethylene Sales Agreement, the Feedstock Supply Agreement and the related services and secondment agreement will become terminable by either party commencing December 31, 2026. If OpCo were unable to reach agreement with Westlake on an extension or replacement of these agreements, then our ability to make distributions on our common units could be materially adversely affected and the value of our common units could decline.

Westlake has (1) leased to OpCo the real property underlying Lake Charles Olefins and Calvert City Olefins and (2) granted OpCo rights to access and use certain other portions of Westlake's ethylene production facilities that are necessary to operate OpCo's units at such ethylene production facilities. The site lease agreements each have a term of 50 years and may be renewed if agreed to by the parties. If an event of default with respect to bankruptcy of OpCo occurs, if Westlake terminates the Ethylene Sales Agreement in accordance with its provisions either for cause or due to a force majeure event, or if OpCo ceases to operate Lake Charles Olefins or Calvert City Olefins for six consecutive months (other than due to force majeure or construction following a casualty loss), Westlake may terminate the applicable site lease following notice and expiration of a cure period to remedy the default. In addition, if OpCo fails to act in good faith to expeditiously restore Lake Charles Olefins or Calvert City Olefins following a casualty loss, Westlake has the ability to terminate the applicable site lease agreement, to restore Lake Charles Olefins or Calvert City Olefins, as the case may be, and to purchase such ethylene production facilityfacilities at

Pursuant to a services and secondment agreement, Westlake is obligated to provide OpCo operating services, utility access services and other key site services. Westlake provides the services of certain of its employees, who act as OpCo's agents in operating and maintaining OpCo's ethylene production facilities. If this agreement is terminated or if Westlake or its affiliates fail to satisfactorily provide these services or employees, OpCo would be required to hire labor, provide these services internally or find a third-party provider of these services. Any services or labor OpCo chooses to provide internally may not be as cost effective as those that Westlake or its affiliates provide, particularly in light of OpCo's lack of experience as an independent organization. If OpCo is required to obtain these services or labor from a third party, it may be unable to do so in a timely, efficient and cost-effective manner, the services or labor it receives may be inferior to or more costly than those that Westlake is currently providing, or such services and labor may be unavailable. Moreover, given the integration of OpCo's ethylene production facilities and Westlake's Lake Charles and Calvert City facilities, it may not be practical for us or for a third party to provide site services or labor for OpCo's ethylene production facilities separately.

OpCo's ability to increase throughput volumes through its assets is constrained by the capacity limitations of those assets, which are currently operating at close to full capacity. OpCo's ability to increase its cash flow by selling ethylene to third parties may be limited by the Ethylene Sales Agreement. OpCo's ability to sell ethylene to third parties is limited to available excess capacity, since Westlake has the right to purchase the substantial majority of production from OpCo's facilities through its minimum purchase commitment and option to purchase additional ethylene under the Ethylene Sales Agreement. The Ethylene Sales Agreement provisions may prohibit OpCo from competing effectively for third party business for this excess

production given the limited volumes available for sale. For example, so long as Westlake is not in default under the Ethylene Sales Agreement, Westlake has the right to purchase 95% of OpCo's production in excess of planned capacity.

The amount of cash we have available for distribution depends primarily upon our cash flow, including cash flow from reserves and working capital or other borrowings (including any under our credit facilities,) and not solely on profitability, which will be affected by non-cash items. As a result, we may pay cash distributions during periods when we record net losses for financial accounting purposes and may be unable to pay cash distributions during periods when we record net income. We may be unable to access our revolving credit facilities when we do not have sufficient cash flows to pay cash distributions.

Our strategy to grow our business and increase distributions to unitholders is dependent on our ability to make acquisitions that result in an increase in our cash distributions per unit. If we are unable to make acquisitions of additional interests in OpCo from Westlake on acceptable terms or we are unable to obtain financing for these acquisitions, our future growth and ability to increase distributions will be limited. In addition, we may be unable to make acquisitions from third parties as an alternative avenue to growth. Furthermore, even if we do consummate acquisitions that we believe will be accretive, they may in fact result in a decrease in our cash distributions per unit. Any acquisition involves potential risks, some of which are beyond our control, including, among other things:

If we consummate any future acquisitions, our capitalization and results of operations may change significantly, and unitholders will not have the opportunity to evaluate the economic, financial and other relevant information that we will consider in determining the application of our funds and other resources.

Many of the assets we use to produce ethylene are generally long-lived assets. As a result, some of those assets have been in service for many decades. The age and condition of these assets could result in increased maintenance or repair expenditures. In addition, while we intend to establish cash reserves in order to cover our turnaround expenditures, the amounts we reserve may be insufficient to fully cover such expenditures. Any significant and unexpected increase in these expenditures could adversely affect our results of operations, financial position or cash flows, as well as our ability to pay cash distributions.

Chemical manufacturing facilities may be at greater risk of terrorist attacks than other potential targets in the U.S. As a result, the chemicalchemicals industry responded to the issues surrounding the terrorist attacks of September 11, 2001 by starting initiatives relating to the security of chemicals industry facilities and the transportation of hazardous chemicals in the U.S. Simultaneously, local, state and federal governments began a regulatory process that led to new regulations impacting the security of chemical plant locations and the transportation of hazardous chemicals. Our business or our customers' businesses could be adversely affected because of the cost of complying with these regulations.

Our operations are subject to the usual hazards associated with commodity chemical and plastics manufacturing and the related use, storage, transportation and disposal of feedstocks, products and wastes, including:

All these hazards can cause personal injury and loss of life, catastrophic damage to or destruction of property and equipment and environmental damage, and may result in a suspension of operations and the imposition of civil or criminal penalties. We could become subject to environmental claims brought by governmental entities or third parties. A loss or shutdown of operations over an extended period at any one of our three major operating facilities would have a material adverse effect on us. We maintain property, business interruption and casualty insurance that we believe is in accordance with customary industry practices, but we cannot be fully insured against all potential hazards incident to our business, including losses resulting from war risks or terrorist acts. As a result of market conditions, premiums and deductibles for certain insurance policies can increase substantially and, in some instances, certain insurance may become unavailable or available only for reduced amounts of coverage. If we were to incur a significant liability for which we were not fully insured, it could have a material adverse effect on our financial position.

We use hazardous substances and generate hazardous wastes and emissions in our manufacturing operations. Our industry is highly regulated and monitored by various environmental regulatory authorities.authorities such as the Environmental Protection Agency (the "EPA"). As such, we are subject to extensive federal, state and local laws and regulations pertaining to pollution and protection of the environment, health and safety, which govern, among other things, emissions to the air, discharges onto land or waters, the maintenance of safe conditions in the workplace, the remediation of contaminated sites, and the generation, handling, storage, transportation, treatment and disposal of waste materials. Some of these laws and regulations are subject to varying and conflicting interpretations. Many of these laws and regulations provide for substantial fines and potential criminal sanctions for violations and require the installation of costly pollution control equipment or operational changes to limit pollution emissions or reduce the likelihood or impact of hazardous substance releases, whether permitted or not. For example, our petrochemical facilities may require improvements to comply with certain changes in process safety management requirements.

Our operations produce greenhouse gas ("GHG") emissions, which have been the subject of increased scrutiny and regulation. The EPA has adopted rules requiring the reporting of GHG emissions from specified large GHG emission sources on an annual basis including our facilities in Lake Charles and Calvert City. Various jurisdictions have considered or adopted laws and regulations on GHG emissions, with the general aim of reducing such emissions. The EPA currently requires certain industrial facilities to report their GHG emissions, and to obtain permits with stringent control requirements before constructing or modifying new facilities with significant criteria pollutant and GHG emissions. As our chemical manufacturing processes resultprocessing results in GHG emissions, these and other GHG laws and regulations could affect our costs of doing business.

We also may face liability for alleged personal injury or property damage due to exposure to chemicals or other hazardous substances at our facilities or to chemicals that we otherwise manufacture, handle or own. Although these types of claims have

Environmental laws may have a significant effect on the nature and scope of, and responsibility for, cleanup of contamination at our current and former operating facilities, the costs of transportation and storage of raw materials and finished products, the costs of reducing emissions and the costs of the storage and disposal of wastewater. CERCLAThe U.S. Comprehensive Environmental Response, Compensation, and Liability Act ("CERCLA") and similar state laws impose joint and several liability for the costs of remedial investigations and actions on the entities that are deemed responsible for a release of hazardous substances into the environment, including entities that have generated hazardous substances or arranged for their transportation or disposal, as well as the past and present owners and operators of disposal sites. All such potentially responsible parties (or any one of them, including us) may be required to bear all of such costs regardless of fault, legality of the original disposal or ownership of the disposal site. In addition, CERCLA and similar state laws could impose liability for damages to natural resources caused by contamination.

Although we seek to take preventive action, our operations are inherently subject to accidental spills, discharges or other releases of hazardous substances that may make us liable to governmental entities or private parties. This may involve contamination associated with our current and former facilities, facilities to which we sent wastes or by-products for treatment or disposal and other contamination. Accidental discharges may occur in the future, future action may be taken in connection with past discharges, governmental agencies may assess damages or penalties against us in connection with any past or future contamination, or third parties may assert claims against us for damages allegedly arising out of any past or future contamination. In addition, we may be liable for existing contamination related to certain of our facilities for which, in some cases, we believe third parties are liable in the event such third parties fail to perform their obligations.

Terrorist activities, anti-terrorist efforts and other armed conflicts involving the U.S. or other jurisdictions could adversely affect the U.S. and global economies and could prevent us from meeting financial and other obligations. We could experience loss of business, delays or defaults in payments from customers or disruptions of fuel supplies and markets if North American and global utilities are direct targets or indirect casualties of an act of terror or war. Terrorist activities and the threat of potential terrorist

Westlake owns and controls our general partner and appoints all of the directors of our general partner. Although our general partner has a duty to manage us in a manner that it believes is not adverse to our interests, the executive officers and directors of our general partner have a fiduciary duty to manage our general partner in a manner beneficial to Westlake. Therefore, conflicts of interest may arise between Westlake or any of its affiliates, including our general partner, on the one hand, and us or any of our unitholders, on the other hand. In resolving these conflicts of interest, our general partner may favor its own interests and the interests of its affiliates over the interests of our common unitholders. These conflicts include the following situations, among others:

In addition, we may compete directly with Westlake and entities in which it has an interest for acquisition opportunities and potentially will compete with these entities for new business or extensions of the existing services provided by us. Please read "Westlake and other affiliates of our general partner may compete with us."

The board of directors adopted a cash distribution policy pursuant to which we intend to distribute quarterly at least $0.2750 per unit on all of our units to the extent we have sufficient cash after the establishment of cash reserves and the payment of our expenses, including payments to our general partner and its affiliates. However, the board may change such policy at any time at its discretion and could elect not to pay distributions for one or more quarters.

In addition, our partnership agreement does not require us to pay any distributions at all. Accordingly, investors are cautioned not to place undue reliance on the permanence of such a policy in making an investment decision. Any modification or revocation of our cash distribution policy could substantially reduce or eliminate the amount we distribute to our unitholders. The amount of distributions we make, if any, and the decision to make any distribution at all will be determined by the board of directors, whose interests may differ from those of our common unitholders. Our general partner has limited duties to our unitholders, which may permit it to favor its own interests or the interests of Westlake to the detriment of our common unitholders.

Our general partner intends to limit its liability under contractual arrangements between us and third parties so that the counterparties to such arrangements have recourse only against our assets, and not against our general partner or its assets. Our general partner may therefore cause us to incur indebtedness or other obligations that are nonrecourse to our general partner. Our partnership agreement provides that any action taken by our general partner to limit its liability is not a breach of our general partner's duties, even if we could have obtained more favorable terms without the limitation on liability.

We plan to distribute most of our available cash, which may cause our growth to proceed at a slower pace than that of businesses that reinvest their 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 our partnership agreement 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 cash that we have available to distribute to our unitholders.

Our partnership agreement contains provisions that eliminate and replace the fiduciary standards to which our general partner would otherwise be held by state fiduciary duty law. For example, our partnership agreement permits our general partner to make a number of decisions in its individual capacity, as opposed to in its capacity as our general partner, or otherwise free of fiduciary duties to us and our unitholders. This entitles our general partner to consider only the interests and factors that it desires and relieves it of any duty or obligation to give any consideration to any interest of, or factors affecting, us, our affiliates or our limited partners. Examples of decisions that our general partner may make in its individual capacity include:

By purchasing a common unit, a unitholder is treated as having consented to the provisions in the partnership agreement, including the provisions discussed above.

Our partnership agreement contains provisions that restrict the remedies available to unitholders for actions taken by our general partner that might otherwise constitute breaches of fiduciary duty under state fiduciary duty law. For example, our partnership agreement provides that:

In connection with a situation involving a transaction with an affiliate or a conflict of interest, other than one where our general partner is permitted to act in its sole discretion, any determination by our general partner must be made in good faith. If an affiliate transaction or the resolution of a conflict of interest is not approved by our common unitholders or the conflicts committee, then it will be presumed that, in making its decision, taking any action or failing to act, the board of directors 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.

Our partnership agreement provides that the conflicts committee of the board of directors may be comprised of one or more independent directors. If the board of directors establishes a conflicts committee with only one independent director, your interests may not be as well served as if the conflicts committee was comprised of at least two independent directors. A single-member conflicts committee would not have the benefit of discussion with, and input from, other independent directors.

Affiliates of our general partner, including Westlake, are not prohibited from engaging in other businesses or activities, including those that might be in direct competition with us. In addition, Westlake may compete with us for investment opportunities and may own an interest in entities that compete with us.

Pursuant to the terms of our partnership agreement, the doctrine of corporate opportunity, or any analogous doctrine, does not apply to our general partner or any of its affiliates, including its executive officers and directors and Westlake. Any such person or entity that becomes aware of a potential transaction, agreement, arrangement or other matter that may be an opportunity for us will not have any duty to communicate or offer such opportunity to us. Any such person or entity will not be liable to us or to any limited partner for breach of any fiduciary duty or other duty by reason of the fact that such person or entity pursues or acquires such opportunity for itself, directs such opportunity to another person or entity or does not communicate such opportunity or information to us. This may create actual and potential conflicts of interest between us and affiliates of our general partner and result in less than favorable treatment of us and our unitholders.

The holder or holders of a majority of our incentive distribution rights (currently Westlake) have the right, at any time when there are no subordinated units outstanding and we have made cash distributions in excess of the then-applicable third target distribution for each of the prior four consecutive fiscal quarters, to reset the initial target distribution levels at higher levels based on our cash distribution levels at the time of the exercise of the reset election. Following a reset election by such

Westlake, as the current holder of our incentive distribution rights, could exercise this reset right in order to facilitate acquisitions or internal growth projects that would not be sufficiently accretive to cash distributions per unit without such conversion. However, Westlake may transfer the incentive distribution rights at any time. It is possible that Westlake or a transferee could exercise this reset election at a time when we are experiencing declines in our aggregate cash distributions or at a time when the holders of the incentive distribution rights expect that we will experience declines in our aggregate cash distributions in the foreseeable future. In such situations, a holder of the incentive distribution rights may be experiencing, or may expect to experience, declines in the cash distributions it receives related to the incentive distribution rights and may therefore desire to be issued our common units rather than retain the right to receive incentive distributions based on the initial target distribution levels. As a result, a reset election may cause our common unitholders to experience reduction in the amount

Compared to the holders of common stock in a corporation, unitholders have limited voting rights and, therefore, limited ability to influence management's decisions regarding our business. Unitholders will have no right on an annual or ongoing basis to elect our general partner or its board of directors. The board of directors, including the independent directors, is chosen entirely by Westlake, as a result of it owning our general partner, and not by our unitholders. Unlike publicly traded corporations, we will not conduct annual meetings of our unitholders to elect directors or conduct other matters routinely conducted at annual meetings of stockholders of corporations. As a result of these limitations, the price at which the common units trade could be diminished because of the absence or reduction of a takeover premium in the trading price.

Our general partner may transfer its general partner interest to a third party without the consent of our unitholders. Furthermore, our partnership agreement permits Westlake to transfer ownership of our general partner to a third party, also without the consent of our unitholders. The new owner of our general partner would then be in a position to replace the board of directors and executive officers of our general partner with its own designees and thereby exert significant control over the decisions taken by the board of directors and executive officers of our general partner. This effectively permits a "change of control" without the vote or consent of the unitholders.

Westlake may transfer the incentive distribution rights to a third party at any time without the consent of our unitholders. If Westlake transfers the incentive distribution rights to a third party, it would not have the same incentive to grow our partnership and increase quarterly distributions to unitholders over time. For example, a transfer of incentive distribution rights by Westlake could reduce the likelihood of it accepting offers made by us relating to assets owned by Westlake, as it would have less of an economic incentive to grow our business, which in turn would impact our ability to grow our asset base.

If at any time our general partner and its affiliates own more than 80% of the common units, our general partner will have the right, which it may assign to any of its affiliates or to us, but not the obligation, to acquire all, but not less than all, of the common units held by unaffiliated persons at a price equal to the greater of (1) the average of the daily closing price of the common units over the 20 trading days preceding the date three days before notice of exercise of the call right is first mailed and (2) the highest per-unit price paid by our general partner or any of its affiliates for common units during the 90-day period preceding the date such notice is first mailed. As a result, unitholders may be required to sell their common units at an undesirable time or price and may not receive any return or a negative return on their investment. Unitholders may also incur a tax liability upon a sale of their units. Our general partner is not obligated to obtain a fairness opinion regarding the value of the common units to be repurchased by it upon exercise of the limited call right. There is no restriction in our partnership agreement that prevents our general partner from causing us to issue additional common units and then exercising its call right. If our general partner exercised its limited call right, the effect would be to take us private and, if the units were subsequently deregistered, we would no longer be subject to the reporting requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act.

Our partnership agreement does not limit the number of additional limited partner interests we may issue at any time without the approval of our unitholders. The issuance of additional common units or other equity interests of equal or senior rank will have the following effects:

All of the subordinated units will convert into common units on a one-for-one basis at the end of the subordination period. Additionally, Westlake has registration rights with respect to the common units it holds. Sales by Westlake or other large holders of a substantial number of our common units in the public markets, or the perception that such sales might occur, could have a material adverse effect on the price of our common units or could impair our ability to obtain capital through an offering of equity securities.

Our partnership agreement restricts unitholders' voting rights by providing that any units held by a person or group that owns 20% or more of any class of units then outstanding, other than our general partner and its affiliates, their transferees and persons who acquired such units with the prior approval of the board of directors, cannot vote on any matter.

We are obligated under our partnership agreement to reimburse our general partner and its affiliates for all expenses they incur and payments they make on our behalf, including expenses we and OpCo will incur under the services and secondment agreement and the omnibus agreement. Our partnership agreement does not set a limit on the amount of expenses for which our general partner and its affiliates may be reimbursed. These expenses include all expenses incurred under the services and secondment agreement and the omnibus agreement, including 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. Our partnership agreement provides that our general partner will determine the expenses that are allocable to us. The reimbursement of expenses and payment of fees, if any, to our general partner and its affiliates will reduce the amount of our earnings and, thereby, our ability to distribute cash to our unitholders.

Under certain circumstances, unitholders may have to repay amounts wrongfully returned or distributed to them. Under Section 17-607 of the Delaware Revised Uniform Limited Partnership Act, or the Delaware Act, we may not make a distribution to our unitholders if the distribution would cause our liabilities to exceed the fair value of our assets. Delaware law provides that for a period of three years from the date of the impermissible distribution, limited partners who received the distribution and who knew at the time of the distribution that it violated Delaware law will be liable to the limited partnership for the distribution amount. Liabilities to partners on account of their partnership interests and liabilities that are non-recourse to the partnership are not counted for purposes of determining whether a distribution is permitted.

Effective internal controls are necessary for us to provide reliable financial reports, prevent fraud and operate successfully as a public company. If we cannot provide reliable financial reports or prevent fraud, our reputation and operating results would be harmed. We cannot be certain that our efforts to maintain our internal controls will be successful, that we will be able to maintain adequate controls over our financial processes and reporting in the future or that we will be able to comply with our obligations under Section 404 of Sarbanes-Oxley. Any failure to maintain effective internal controls, or difficulties encountered

in implementing or improving our internal controls, could harm our operating results or cause us to fail to meet our reporting obligations. Ineffective internal controls could also cause investors to lose confidence in our reported financial information, which would likely have a negative effect on the trading price of our units.

The anticipated after-tax economic benefit of an investment in our common units depends largely on our being treated as a partnership for federal income tax purposes.

Despite the fact that we are organized as a limited partnership under Delaware law, we would be treated as a corporation for U.S. federal income tax purposes unless we satisfy a "qualifying income" requirement.requirement (the "Qualifying Income Exception") under Section 7704 of the Internal Revenue Code of 1986, as amended (the "Code"). Failure to meet the Qualifying Income Exception would cause us to be treated as a corporation for U.S. federal income tax purposes. Based upon our current operations, we believe we satisfy the qualifying income requirement. We have

Prior to our initial public offering, we requested and obtained a favorable private letter ruling from the IRS to the effect that, based on facts presented in the private letter ruling request, our income from the production, transportation, storage and marketing of ethylene and its co-products will constituteconstitutes "qualifying income" within the meaning of Section 7704 of the Code. However, no ruling has been or will be requested from the IRS regarding our treatment as a partnership for U.S. federal income tax purposes. FailingFailure to meet the qualifying income requirement or a change in current law could cause us to be treated as a corporation for U.S. federal income tax purposes or otherwise subject us to taxation as an entity.

If we were treated as a corporation for federal income tax purposes, we would pay U.S. federal income tax on our taxable income at the corporate tax rate, which is currently a maximum of 35%.rate. Distributions to youour unitholders would generally be taxed again as corporate distributions, and no income, gains, losses or deductions would flow through to you.our unitholders. Because a tax would be imposed upon us as a corporation, our cash available for distribution to youour unitholders 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 theour unitholders, likely causing a substantial reduction in the value of our common units.

Our partnership agreement provides that if a law is enacted or existing law is modified or interpreted in a manner that subjects us to taxation as a corporation or otherwise subjects us to entity-level taxation for U.S. federal, state, local or foreign income tax purposes, the minimum quarterly distribution amount and the target distribution amounts may be adjusted to reflect

Any modification to the U.S. federal income tax laws may be applied retroactively and could make it more difficult or impossible for us to meet the exception for certain publicly traded partnerships to be treated as partnerships for U.S. federal

The IRS may adopt positions that differ from the positions we take. It may be necessary to resort to administrative or court proceedings to sustain some or all of the positions we take. A court may not agree with some or all of the positions we take. Any contest with the IRS may materially and adversely impact the market for our common units and the price at which they trade. Moreover, the costs of any contest between us and the IRS will result in a reduction in our cash available for distribution to our unitholders and thus will be borne indirectly by our unitholders.

You will beUnitholders are required to pay federal income taxes and, in some cases, state and local income taxes, on yourunitholders’ share of our taxable income, whether or not youthey receive cash distributions from us. YouUnitholders may not receive cash distributions from us equal to yourtheir share of our taxable income or even equal to the actual tax due from youthem with respect to that income.

If you sell youra unitholder sells common units, youthe unitholder will recognize a gain or loss equal to the difference between the amount realized and yourthat unitholder’s tax basis in those common units. Because distributions in excess of youra unitholder’s allocable share of our net taxable income decrease yoursuch unitholder’s tax basis in yourits common units, the amount, if any, of such prior excess distributions with respect to the units you sella unitholder sells will, in effect, become taxable income to youa unitholder if you sellit sells such units at a price greater than yourits tax basis in those units, even if the price you receivesuch unitholder receives is less than yourits original cost. Furthermore, a substantial portion of the amount realized, whether or not representing gain, may be taxed as ordinary income due to potential recapture items, including depreciation recapture. In addition, because the amount realized includes a unitholder'sunitholder’s share of our nonrecourse liabilities, if you sell youra unitholder sells its units, youa unitholder may incur a tax liability in excess of the amount of cash you receivereceived from the sale.

Non-U.S. unitholders are generally taxed and subject to income tax filing requirements by the United States on income effectively connected with a U.S. trade or business (“effectively connected income”). Income allocated to our unitholders and any gain from the sale of our units will generally be considered to be “effectively connected” with a U.S. trade or business.  As a result, distributions to a Non-U.S. unitholder will be subject to withholding taxes at the

The Tax Cuts and Jobs Act imposes a withholding obligation of 10% of the amount realized upon a Non-U.S. unitholder’s sale or exchange of an interest in a partnership that is engaged in a U.S. trade or business. However, due to challenges of administering a withholding obligation applicable to open market trading and other complications, the IRS has temporarily suspended the application of this withholding rule to open market transfers of interests in publicly traded partnerships pending promulgation of regulations or other guidance that resolves the challenges.  It is not clear if or when such regulations or other guidance will be required to file U.S. federalissued.  Non-U.S. unitholders should consult a tax returns and pay tax on their share ofadvisor before investing in our taxable income.common units.

Because we cannot match transferors and transferees of common units, and because of other reasons, we will adopthave adopted certain methods for allocating depreciation and amortization positionsdeductions that may not conform to all aspects of existing Treasury Regulations. A successful IRS challenge to those positionsthe use of these methods could adversely affect the amount of tax benefits available to you.our unitholders. It also could affect the timing of these tax benefits or the amount of gain from yourany sale of common units and could have a negative impact on the value of our common units or result in audit adjustments to youra unitholder’s tax returns.

We generally prorate our items of income, gain, loss and deduction between transferors and transferees of our units each month based upon the ownership of our units on the first day of each month (the “Allocation Date”), instead of on the basis of the date a particular unit is transferred. The useSimilarly, we generally allocate certain deductions for depreciation of this proration method may not be permitted under existing Treasury regulations. The U.S. Treasury Department has issued proposedcapital additions, gain or loss realized on a sale or other disposition of our assets and, in the discretion of the general partner, any other extraordinary item of income, gain, loss or deduction based upon ownership on the Allocation Date. Treasury Regulations that provide a safe harbor pursuant to which a publicly traded partnership may useallow a similar monthly simplifying convention, to allocate tax items among transferor and transferee unitholders. Nonetheless, the proposedbut such regulations do not specifically authorize the useall aspects of theour proration method we have adopted.

method. If the IRS were to challenge our proration method, or new Treasury Regulations were issued, we may be required to change the allocation of items of income, gain, loss and deduction among our unitholders.

Because there are no specific rules governing the U.S. federal income tax consequence of loaning a partnership interest, a unitholder whose units are the subject of a securities loan may be considered as havingto have disposed of the loaned units. In that case, the unitholder may no longer be treated for tax purposes as a partner with respect to those units during the period of the loan to the short seller and the unitholder may recognize gain or loss from such disposition. Moreover, during the period of the loan, any of our income, gain, loss or deduction with respect to those units may not be reportable by the unitholder and any cash distributions received by the unitholder as to those units could be fully taxable as ordinary income. Unitholders desiring to assure their status as partners and avoid the risk of gain recognition from a securities loan are urged to consult a tax advisor to determine whether it is advisable to modify any applicable brokerage account agreements to prohibit their brokers from borrowing their units.

In determining the items of income, gain, loss and deduction allocable to our unitholders, we must routinely determine the fair market value of our respective assets. Although we may, from time to time, consult with professional appraisers regarding valuation matters, we make many fair market value estimates using a methodology based on the market value of our common units as a means to measure the fair market value of our respective assets. The IRS may challenge these valuation methods and the resulting allocations of income, gain, loss and deduction.

A successful IRS challenge to these methods or allocations could adversely affect the timing or amount character, and timing of taxable income or loss being allocated to our unitholders. It also could affect the amount of gain recognized from our unitholders'the sale of our common units, and could have a negative impact on the value of theour common units or result in audit adjustments to our unitholders'unitholders’ tax returns without the benefit of additional deductions.

In addition to U.S. federal income taxes, youour unitholders may be subject to other taxes, including foreign, state and local taxes, unincorporated business taxes and estate, inheritance or intangible taxes that are imposed by the various jurisdictions in which we conduct business or own property now or in the future, even if youthey do not live in any of those jurisdictions. YouOur unitholders will likely be required to file foreign, state and local income tax returns and pay state and local income taxes in some or all of these various jurisdictions. Further, youour unitholders may be subject to penalties for failure to comply with those requirements.

Item 1B. Unresolved Staff Comments

Item 2. Properties

Information regarding our properties is contained in "Item 1. Business—OpCo's Assets" and "Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations."

Item 3. Legal Proceedings

In the ordinary conduct of our business, we and Westlake and Westlake's subsidiaries, including OpCo, are subject to periodic lawsuits, investigations and claims, including environmental claims and employee related matters. See the discussion

Item 5. Market for Registrant's Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities

Our common units are listed and traded on the New York Stock Exchange ("NYSE") under the symbol "WLKP." Our common units began trading on July 30, 2014 at an initial offering price of $24.00 per unit. Prior to July 30, 2014, our units were not listed on any exchange and there was no public market for our units. The following table sets forth for the indicated periods the high and low sales prices per unit for our common units on the NYSE:

As of the close of business on March 2, 2015,February 22, 2018, based upon information received from our transfer agent, there were approximately 14,373,615 unitholderstwo holders of record of our common units. This number does not include unitholders whose units are held in trust by other entities. The actual number of beneficial owners of the common units is greater than the number of holders of record. We have also issued 12,686,115 subordinated units, for which there is no established public trading market. All of the subordinated units are held by Westlake. The principal difference between our common units and subordinated units is that for any quarter during the subordination period, holders of the subordinated units are not entitled to receive any distribution from operating surplus until the common units have received the minimum quarterly distribution from operating surplus for such quarter plus any arrearages in the payment of the minimum quarterly distribution from prior quarters. Subordinated units will not accrue arrearages. When the subordination period ends, all of the subordinated units will convert into an equal number of common units.

Cash distributions paid to unitholders for the yearyears ended December 31, 20142017 and 2016 were as follows:

We are a publicly traded partnership and are not subject to federal income tax. Instead, unitholders are required to report their allocable share of our income, gain, loss and deduction, regardless of whether we make distributions.

Set forth below is a summary of the significant provisions of our partnership agreement that relate to cash distributions, minimum quarterly distributions and incentive distribution rights.

Our partnership agreement provides that our general partner will make a determination as to whether to make a distribution, but our partnership agreement does not require us to pay distributions at any time or in any amount. Instead, the

board of directors adopted a cash distribution policy in connection with the closing of the IPO that sets forth our general partner's intention with respect to the distributions to be made to unitholders. Pursuant to our cash distribution policy, within 60 days after the end of each quarter, we intend to make a minimum quarterly distribution of $0.2750 per unit to the extent we have sufficient cash after establishment of cash reserves and payment of fees and expenses, including payments to our general partner and its affiliates.

The board of directors may change our cash distribution policy at any time and from time to time, and even if our cash distribution policy is not modified or revoked, the amount of distributions paid under our policy and the decision to make any distribution is determined by our general partner.

Any distribution we make is characterized as made from "operating surplus" or "capital surplus." Distributions from operating surplus are made differently than cash distributions we would make from capital surplus. Operating surplus distributions will be made to our unitholders and, if we make quarterly distributions above the first target distribution level described below, to the holder of our incentive distribution rights. We do not anticipate that we will make any distributions from capital surplus. In such an event, however, any capital surplus distribution would be made pro rata to all unitholders, but the incentive distribution rights would generally not participate in any capital surplus distributions. Any distribution of capital surplus would result in a reduction of the minimum quarterly distribution and target distribution levels and, if we reduce the minimum quarterly distribution to zero and eliminate any unpaid arrearages, thereafter capital surplus would be distributed as if it were operating surplus and the incentive distribution rights would thereafter be entitled to participate in such distributions. In determining operating surplus and capital surplus, we will only take into account our proportionate share of our consolidated subsidiaries that are not wholly owned, such as OpCo.

Our partnership agreement provides that, during the subordination period, the common units will have the right to receive distributions of available cash from operating surplus each quarter in an amount equal to $0.2750 per common unit, which amount is defined in our partnership agreement as the minimum quarterly distribution, plus any arrearages in the payment of the minimum quarterly distribution on the common units from prior quarters, before any distributions of available cash from operating surplus may be made on the subordinated units. These units are deemed "subordinated" because for a period of time, referred to as the subordination period, the subordinated units will not be entitled to receive any distributions from operating surplus until the common units have received the minimum quarterly distribution plus any arrearages in the payment of the minimum quarterly distribution from prior quarters. Furthermore, no arrearages will be paid on the subordinated units. The practical effect of the subordinated units is to increase the likelihood that during the subordination period there will be sufficient available cash from operating surplus to pay the minimum quarterly distribution on the common units. Following the Partnership’s cash distribution for the second quarter of 2017, the requirement under the Partnership’s partnership agreement for the conversion of all subordinated units was satisfied. As a result, effective August 30, 2017, all the 12,686,115 subordinated units owned by Westlake were converted into common units on a one-for-one basis and thereafter participate on terms equal with all other common units in distributions of available cash.

Our general partner owns a non-economic general partner interest in us, which does not entitle it to receive cash distributions. However, our general partner may in the future own common units or other equity interests in us and will be entitled to receive distributions on any such interests.

Incentive distribution rights represent the right to receive increasing percentages (15.0%, 25.0% and 50.0%) of quarterly distributions from operating surplus after the minimum quarterly distribution and the target distribution levels have been achieved. Westlake currently holds the incentive distribution rights, but may transfer these rights separately from its general partner interest.

None.