8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

December 3, 2012

Date of Report (Date of earliest event reported)

WESTERN GAS PARTNERS, LP

(Exact name of Registrant as specified in its charter)

Delaware	001-34046	26-1075808
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification Number)

1201 Lake Robbins Drive

The Woodlands, Texas 77380-1046

(Address of principal executive offices)

(832) 636-6000

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01. Regulation FD Disclosure.

On December 3, 2012, Western Gas Equity Partners, LP (“WGP”), a wholly owned subsidiary of Anadarko Petroleum Corporation (“Anadarko”), filed an Amendment to its Registration Statement on Form S-1 (File No. 333-184763) (as it may be amended from time to time, the “Registration Statement”) with the U.S. Securities and Exchange Commission (the “SEC”) relating to the proposed initial public offering of common units representing limited partner interests in WGP (the “WGP Offering”). WGP holds the 40,573,239 common units of Western Gas Partners, LP (“WES,” “we,” “our,” or “us”) indirectly owned by Anadarko and a 100% membership interest in our general partner, Western Gas Holdings, LLC.

For Regulation FD purposes, WES wishes to disclose certain information pertaining to the use of proceeds from the proposed WGP Offering and WGP’s estimation of the minimum Adjusted EBITDA that WES needs to generate to enable WGP to pay its annualized initial quarterly distribution for the year ending December 31, 2013, which information is furnished in Exhibit 99.1 hereto and is incorporated herein by reference (the “WGP S-1 Excerpt”). As indicated in the WGP S-1 Excerpt, the baseline estimate of WES Adjusted EBITDA should not be viewed as management’s full projection of WES’s expected operating results and financial performance for the year ending December 31, 2013. Similarly, such baseline estimate is not intended to modify or replace the guidance that WES provides on an annual basis. WES’s management believes that WES’s actual Adjusted EBITDA during the year ending December 31, 2013 will exceed the amount presented therein.

The Registration Statement relating to the common units of WGP has been filed with the SEC, but has not yet become effective. Such common units may not be sold nor may offers to buy be accepted prior to the time the Registration Statement becomes effective. Neither this Current Report on Form 8-K nor the information contained herein shall constitute an offer to sell or the solicitation of an offer to buy such common units nor shall there be any sale of such common units in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

This Current Report on Form 8-K contains forward-looking statements concerning our operations, economic performance and financial condition. These statements can be identified by the use of forward-looking terminology, including “may,” “will,” “believe,” “expect,” “anticipate,” “estimate,” “continue,” or other similar words. These statements discuss future expectations, contain projections of results of operations or financial condition or include other “forward-looking” information. Although we and our general partner believe that the expectations reflected in such forward-looking statements are reasonable, we and our general partner can give no assurance that such expectations will prove to have been correct.

These forward-looking statements involve risks and uncertainties. Important factors that could cause actual results to differ materially from our expectations include, but are not limited to, the following risks and uncertainties:

• our assumptions about the energy market;

• future throughput, including Anadarko’s production, which is gathered or processed by or transported through our assets;

• operating results;

• competitive conditions;

• technology;

• the availability of capital resources to fund acquisitions, capital expenditures and other contractual obligations, and our ability to access those resources from Anadarko or through the debt or equity capital markets;

• the supply of, the demand for, and the prices of oil, natural gas, NGLs and related products or services;

• the weather;

• inflation;

• the availability of goods and services;

• general economic conditions, either internationally or nationally or in the jurisdictions in which we are doing business;

• changes in environmental and safety regulations; environmental risks; regulations by the Federal Energy Regulatory Commission; and liability under federal and state laws and regulations;

• legislative or regulatory changes affecting our status as a partnership for federal income tax purposes;

• changes in the financial or operational condition of our sponsor, Anadarko;

• changes in Anadarko’s capital program, strategy or desired areas of focus;

• our commitments to capital projects and the ability to complete such projects on time and within budget expectations;

• the ability to utilize our revolving credit facility;

• the creditworthiness of Anadarko or our other counterparties, including financial institutions, operating partners, and other parties;

• our ability to repay debt;

• our ability to maintain and/or obtain rights to operate our assets on land owned by third parties;

• our ability to acquire assets on acceptable terms;

• non-payment or non-performance of Anadarko or other significant customers, including under our gathering, processing and transportation agreements and our $260.0 million note receivable from Anadarko;

• the timing, amount and terms of future issuances of equity and debt securities;

• the timing, completion and proceeds of the WGP Offering; and

• other factors discussed in “Risk Factors” included in our 2011 Form 10-K, in “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates” included in our Current Report on Form 8-K filed May 22, 2012, in our quarterly reports on Form 10-Q and elsewhere in our other public filings and press releases.

The risk factors and other factors noted or incorporated by reference in this report could cause our actual results to differ materially from those contained in any forward-looking statement. We undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise

In accordance with General Instruction B.2, the information contained in this report is being “furnished” to the U.S. Securities and Exchange and shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities under such section. Furthermore, such information shall not be deemed to be incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, unless specifically identified as being incorporated therein by reference.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Exhibit Number	Description of the Exhibit
Exhibit 99.1	WGP S-1 Excerpt

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	WESTERN GAS PARTNERS, LP
	By:	Western Gas Holdings, LLC,
		its general partner
Date: December 3, 2012	By:	/s/ Philip H. Peacock
		Philip H. Peacock
		Vice President, General Counsel and Corporate Secretary

EXHIBIT INDEX

Exhibit Number	Description of the Exhibit
Exhibit 99.1	WGP S-1 Excerpt

EX-99.1

Exhibit 99.1

The following is an excerpt from the Registration Statement of Western Gas Equity Partners, LP filed on December 3, 2012. Throughout this excerpt, when the terms “WGP,” “we,” “us,” “our” and “Western Gas Equity Partners, LP,” are used, they refer to Western Gas Equity Partners, LP in its individual capacity or to Western Gas Equity Partners, LP and its consolidated subsidiaries collectively, as the context requires. As used herein, (i) “our general partner” refers to Western Gas Equity Holdings, LLC, the general partner of Western Gas Equity Partners, LP; (ii) “WES” refers to Western Gas Partners, LP in its individual capacity or to Western Gas Partners, LP and its subsidiaries collectively, as the context requires; (iii) “WES GP” refers to Western Gas Holdings, LLC, a wholly owned subsidiary of Western Gas Equity Partners, LP and the general partner of Western Gas Partners, LP; (iv) “Anadarko” refers to Anadarko Petroleum Corporation and its subsidiaries and affiliates, other than Western Gas Equity Partners, LP, its general partner, WES GP, WES, and its subsidiaries as of the closing date of the initial public offering of Western Gas Equity Partners, LP; and (v) “Anadarko Petroleum Corporation” refers to Anadarko Petroleum Corporation excluding its subsidiaries and affiliates.

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USE OF PROCEEDS

We expect to receive net proceeds of approximately $281.5 million from the sale of our common units assuming an initial public offering price of $20.00 per common unit (the midpoint of the price range set forth on the cover page of this prospectus), after deducting underwriting discounts, the structuring fee and offering expenses. We will use the net proceeds from this offering as follows:

• to purchase from WES 5,997,174 common units representing limited partner interests in WES for approximately $275.9 million; and

• to make a capital contribution to WES on behalf of WES GP of approximately $5.6 million in exchange for 122,391 WES general partner units in order to maintain WES GP’s 2.0% general partner interest in WES.

We will use any net proceeds from the exercise of the underwriters’ over-allotment option to purchase from WES additional common units and a corresponding number of general partner units.

Please read “Prospectus Summary—Our Structure” for a discussion of the impact on our equity capitalization of a change in the public offering price of our common units or the number of common units sold in this offering.

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Estimated Minimum Necessary WES Adjusted EBITDA to Enable Us to Pay the Aggregate Annualized Initial Quarterly Distribution for the Year Ending December 31, 2013

In order to have sufficient available cash to pay the aggregate annualized initial quarterly distribution on all of our outstanding common units for the year ending December 31, 2013, we estimate that we must receive cash distributions from WES of at least $140.6 million. In order for WES to pay us cash distributions that would permit us to pay the full initial quarterly distribution on all of our outstanding common units for the year ending December 31, 2013 (including the additional common units that we would issue if the offering price or size were increased to yield aggregate gross offering proceeds of approximately $435 million), we estimate that WES must generate Adjusted EBITDA of at least $340.0 million. WES defines Adjusted EBITDA as net income (loss) attributable to Western Gas Partners, LP, plus distributions from equity investees, non-cash equity–based compensation expense, expense in excess of the expense reimbursement cap provided in the WES omnibus agreement (if applicable), interest expense, income tax expense, depreciation, amortization and impairments, and other expense, less income from equity investments, interest income, income tax benefit, and other income. Adjusted EBITDA should not be considered an alternative to net income, net cash provided by operating activities, or any other measure of financial performance calculated in accordance with generally accepted accounting principles in the United States (“GAAP”).

The table below is intended to be an indicator or benchmark of the amount management considers to be the minimum amount of WES Adjusted EBITDA necessary for WES to pay distributions to its partners, including us, which will enable us to have sufficient available cash to pay the initial quarterly distribution of $0.165 per common unit per quarter (or $0.660 per common unit on an annualized basis) on our common units for the year ending December 31, 2013 (including the additional common units that we would issue if the offering price or size were increased to yield aggregate gross offering proceeds of approximately $435 million). The baseline estimate of WES Adjusted EBITDA should not be viewed as management’s full projection of WES’s expected operating results and financial performance for the year ending December 31, 2013. Similarly, such baseline estimate is not intended to modify or replace the guidance that WES provides on an annual basis. Our management believes that WES’s actual Adjusted EBITDA during the year ending December 31, 2013 will exceed the amount presented below.

We believe that our partnership interests in WES, including the incentive distribution rights, will generate sufficient cash flow to enable us to pay the aggregate annualized initial quarterly distribution on all of our common units for the year ending December 31, 2013. You should read the footnotes to the table below for a discussion of the material assumptions underlying this belief. Our belief is based on several assumptions and reflects our judgment of conditions we expect to exist and the course of action we expect WES to take. While we believe that these assumptions are reasonable in light of our current expectations regarding future events, the assumptions underlying our belief are inherently uncertain and are subject to significant business, economic, regulatory and competitive risks and uncertainties that could cause actual results to differ materially from those we anticipate. If WES’s expected results of operations are not realized, the amount of cash that WES distributes to us could be substantially less than that currently expected and could, therefore, be insufficient to permit us to pay the initial quarterly distribution, or any distribution, on our common units, which could cause the market price of our common units to decline materially. Consequently, our belief that we will have sufficient available cash to pay the initial quarterly distribution on all of our common units for the year ending December 31, 2013 should not be regarded as a representation by us, the underwriters or any other person that we will declare and pay such a distribution.

We have prepared the table below and related disclosure to substantiate our belief that we will have sufficient available cash to pay the aggregate annualized initial quarterly distribution on all of our common units for the year ending December 31, 2013. The statements made below are forward-looking statements and should be read together with the historical and pro forma financial statements and the accompanying notes included elsewhere in this prospectus and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” The financial information below was not prepared with a view toward complying with the

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guidelines established by the American Institute of Certified Public Accountants with respect to prospective financial information, but, in the view of our management, was prepared on a reasonable basis, reflects the best currently available estimates and judgments, and presents, to the best of management’s knowledge and belief, the assumptions on which we base our belief that we can generate sufficient available cash to pay the aggregate annualized initial quarterly distribution on all of our common units for the year ending December 31, 2013. However, this information is not fact and should not be relied upon as being necessarily indicative of future results, and we undertake no obligation to release publicly the results of any future revisions we may make to this financial information to reflect events or circumstances after the date of this prospectus. As a result, readers of this prospectus are cautioned not to place undue reliance on this financial information.

Neither our independent auditors nor any other independent accountants have compiled, examined or performed any procedures with respect to the prospective financial information contained herein, nor have they expressed any opinion or any other form of assurance on such information or its achievability, and they assume no responsibility for, and disclaim any association with, the prospective financial information.

When reading this section, you should keep in mind the risk factors and other cautionary statements under the heading “Risk Factors” in this prospectus. Any of these factors or the other risks discussed in this prospectus could cause our financial condition and consolidated results of operations to vary significantly from those set forth in the table below.

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Western Gas Equity Partners, LP

Estimated Minimum Necessary WES Adjusted EBITDA

	Year Ending December 31, 2013
	(in thousands, except ratio)
Western Gas Partners, LP
Estimated Minimum Necessary Adjusted EBITDA attributable to Western Gas Partners, LP (1)	$	339,977
Less:
Cash interest expense (2)		55,848
Cash income taxes (3)		249
Maintenance capital expenditures (4)		38,150
Plus:
Cash interest income (5)		16,900
Estimated available cash of Western Gas Partners, LP	$	262,630
Less:
Expansion capital expenditures (6)		325,901
Plus:
Borrowings to fund expansion capital expenditures (7)		44,401
Proceeds from sale of units to WGP to fund expansion capital expenditures (7)		281,500
Estimated available cash of Western Gas Partners, LP	$	262,630
Distributions to non-affiliated owners of WES (8)	$	115,158
Distributions to Western Gas Equity Partners, LP (8)
2% general partner interest		5,116
Incentive distribution rights		38,649
Common units		96,866
Total distributions to Western Gas Equity Partners, LP	$	140,631
Total distributions of Western Gas Partners, LP	$	255,789
Excess of estimated available cash of Western Gas Partners, LP over total distributions of Western Gas Partners, LP(8)	$	6,841
Western Gas Equity Partners, LP
Distributions from Western Gas Partners, LP	$	140,631
Less:
General and administrative expenses (9)		3,000
Estimated available cash of Western Gas Equity Partners, LP	$	137,631
Aggregate annualized initial quarterly distribution of Western Gas Equity Partners, LP (8)	$	137,631
WES leverage ratio (10)		3.57x

(1) In order to have sufficient available cash to pay the aggregate annualized initial quarterly distribution on all of our outstanding common units for the year ending December 31, 2013, we estimate that we must receive cash distributions from WES of at least $140.6 million. In order for WES to pay us cash distributions that would permit us to pay the full initial quarterly distribution on all of our outstanding common units for the year ending December 31, 2013 (including the additional common units that we would issue if the offering price or size were increased to yield aggregate gross offering proceeds of approximately $435 million), we estimate that WES must generate Adjusted EBITDA of at least $340.0 million for the year ending December 31, 2013, as compared to pro forma Adjusted EBITDA of $324.3 million and $327.4 million for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively.

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This table is intended to be an indicator or benchmark of the amount management considers to be the lowest amount of WES Adjusted EBITDA necessary for WES to pay distributions to its partners, including us, which will enable us to have sufficient available cash to pay the initial quarterly distribution of $0.165 per common unit per quarter (or $0.660 per common unit on an annualized basis) on our common units for the year ending December 31, 2013 (including the additional common units that we would issue if the offering price or size were increased to yield aggregate gross offering proceeds of approximately $435 million). The baseline estimate of WES Adjusted EBITDA should not be viewed as management’s full projection of WES’s expected operating results and financial performance for the year ending December 31, 2013. Similarly, such baseline estimate is not intended to modify or replace the guidance that WES provides on an annual basis. As discussed in more detail in footnote 8 below, our management believes that WES’s Adjusted EBITDA during the year ending December 31, 2013 will exceed the amount presented below.

Our calculation of estimated throughput presented below represents our estimate of the minimum throughput that we believe necessary for WES to generate sufficient Adjusted EBITDA to enable us to pay our annualized initial quarterly distribution on all of our common units if the aggregate offering size increases as described above. We calculated this estimated minimum throughput as follows:

• We adjusted the estimated minimum Adjusted EBITDA attributable to WES of $340.0 million for certain items, including forecasted property and ad valorem taxes and general and administrative expenses, to derive an estimated minimum gross margin;

• We divided the resulting estimated minimum gross margin into gross margin attributable to (i) gathering, treating and transportation, (ii) processing and (iii) equity investment, based on the percentage that each subset represents in the current 2013 forecast for WES; and

• We divided each category of minimum gross margin by the applicable gross margin per Mcf included in the current 2013 forecast for WES, which yielded a minimum estimated throughput for each category.

The Estimated Minimum Necessary WES Adjusted EBITDA is based on a number of significant assumptions, including the following:

• Total gathering, treating and transportation throughput of 1,196 MMcf/d for the year ending December 31, 2013, as compared to 1,321 MMcf/d and 1,268 MMcf/d for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively.

• Total processing throughput of 1,106 MMcf/d for the year ending December 31, 2013, as compared to 962 MMcf/d and 1,143 MMcf/d for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively.

• Total equity investment throughput of 157 MMcf/d for the year ending December 31, 2013, as compared to 198 MMcf/d and 231 MMcf/d for the year ended December 31, 2011 and twelve months ended September 30, 2012, respectively.

• Reported throughput volumes will continue to exclude average NGL pipeline volumes and WES’s 10% share of White Cliffs pipeline volumes, both of which are measured in barrels. We assume throughput on WES’s NGL pipeline of 26 MBbls/d for the year ending December 31, 2013, as compared to 24 MBbls/d and 26 MBbls/d for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively. We assume throughput attributable to WES’s 10% share of White Cliffs of 6 MBbls/d for the year ending December 31, 2013, as compared to 4 MBbls/d and 6 MBbls/d for the year ended December 31, 2011 and twelve months ended September 30, 2012, respectively.

• Equity income of $17.2 million for the year ending December 31, 2013, as compared to $11.3 million and $14.3 million for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively. The assumed increase is primarily attributable to additional anticipated transportation volumes for the White Cliffs pipeline.

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• Distributions from equity investees of $22.1 million for the year ending December 31, 2013, as compared to $16.0 million and $19.6 million for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively. The assumed increase is primarily related to additional anticipated transportation volumes for the White Cliffs pipeline.

• Equity-based compensation expense related to employees seconded to WES of $2.8 million for the year ending December 31, 2013, as compared to $13.8 million and $23.9 million for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively. The assumed decrease is primarily due to the settlement, in cash, of liabilities related to the Incentive Plan in conjunction with the closing of this offering. We will not have an equity compensation plan similar to the Incentive Plan, in which the value of the awards is tied to the value of the general partner of WES. Although we will have a typical long-term incentive plan, we expect that awards under this plan will be settled in our common units (as opposed to cash-settled liability-based awards granted under the Incentive Plan), and we therefore anticipate significantly lower equity-based compensation expense in the future relative to awards under the Incentive Plan. Please read “Management—Executive Compensation Discussion and Analysis” for more information.

• WES does not consummate any material acquisitions from Anadarko or third parties during the year ending December 31, 2013.

• WES does not issue any common units, general partner units or other partnership securities during the year ending December 31, 2013, other than common units and general partner units to be issued to us in connection with this offering.

• Our general partner does not approve any waiver, reduction, limitation or modification of or to WES’s incentive distribution rights that would alter incentive distributions during the year ending December 31, 2013.

• There will not be any new federal, state or local regulation of the portions of the energy industry in which we and WES operate, or any new interpretations of existing regulations, that will be materially adverse to our or WES’s business.

• There will not be any major adverse change in the portions of the energy industry in which we and WES operate resulting from supply or production disruptions, reduced demand for our products or services, or significant changes in the market prices of natural gas or NGLs.

• Market, insurance and overall economic conditions will not change substantially.

We cannot assure you that any of the assumptions summarized above, or any other assumptions upon which our Estimated Minimum Necessary WES Adjusted EBITDA is based, will prove to be correct. If the assumptions are incorrect or not achieved, we may not have sufficient available cash to make the contemplated distributions.

(2) We assume consolidated cash interest expense of approximately $55.8 million for the year ending December 31, 2013, as compared to $53.7 million for each of the year ended December 31, 2011 and the twelve months ended September 30, 2012 on a pro forma basis. Cash interest expense is assumed to be comprised of the following components:

(i) approximately $2.2 million of interest expense, net of capitalized interest, related to borrowings of $43.4 million under the WES RCF to fund expansion capital expenditures and the additional interest associated with the annual commitment fee of approximately 0.25% on the unused borrowing capacity under the WES RCF. We assume that WES will finance a substantial portion of its expansion capital expenditures through borrowings under the WES RCF. We have assumed that the weighted-average interest rate on the WES RCF during the year ending December 31, 2013 will not exceed 1.74%;

(ii) approximately $26.8 million of interest expense associated with the 2022 Notes; and

(iii) approximately $26.9 million of interest expense associated with the 2021 Notes.

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(3) Represents the amount paid by WES primarily for Texas margin taxes. There will likely be no incremental Texas margin tax attributable to WGP.

(4) We assume maintenance capital expenditures of $38.2 million for the year ending December 31, 2013, as compared to $28.4 million and $33.3 million for the year ended December 31, 2011 and twelve months ended September 30, 2012, respectively. The assumed increase in maintenance capital expenditures is primarily attributable to WES’s growing asset base and the resulting increased integrity expenditures.

(5) Represents cash interest income WES receives annually from Anadarko with respect to the $260.0 million 30-year note bearing interest at a fixed annual rate of 6.50% together with earned interest income on intercompany balances related to assets acquired from Anadarko for periods prior to their acquisition. Beginning December 7, 2011, Anadarko discontinued charging interest on intercompany balances.

(6) We assume expansion capital expenditures of $325.9 million for the year ending December 31, 2013, as compared to $87.5 million and $249.2 million for the year ended December 31, 2011 and the twelve months ended September 30, 2012, respectively. The expected increase in expansion capital expenditures is primarily attributable to amounts WES anticipates spending on the Lancaster Plant, the Brasada Plant, the expansion of the Red Desert system, and the continued expansion of its DJ Basin assets.

(7) Because WES has historically financed organic growth projects and acquisitions through the use of external financing sources, including borrowings under the WES RCF and the issuance of debt and equity securities, and we anticipate that it will continue to do so, we have shown estimated borrowings for these purposes as a source of cash in the table above. Specifically, we assume that WES will fund its $325.9 million of expected expansion capital for the year ending December 31, 2013 by borrowing $44.4 million and using the $281.5 million of net proceeds received by WES from the sale of common units and general partner units to us in connection with this offering. While such net proceeds received by WES are a non-recurring source of funds for WES, we believe that WES will be able to satisfy its liquidity needs subsequent to December 31, 2013, including for funding expansion capital expenditures, through cash and cash equivalents, cash flows generated from operations, including interest income on its $260.0 million note receivable from Anadarko, available borrowings under the WES RCF, and issuances of additional equity or debt securities. We anticipate that WES would have approximately $750 million of available borrowing capacity under the WES RCF as of December 31, 2013 (after giving effect to the projected $44.4 million of borrowings to fund expansion capital expenditures and approximately $6.6 million of letters of credit) as compared to approximately $800 million of available borrowing capacity as of September 30, 2012.

(8) Assumes the following:

• WES will pay a quarterly cash distribution of $0.52 per WES common unit for each quarter, which per unit distribution amount is equal to the anticipated WES cash distribution for the fourth quarter of 2012;

• 101,934,761 and 2,080,302 outstanding WES common units and general partner units, including the assumed 5,997,174 WES common units and 122,391 WES general partner units to be purchased by WGP in connection with the closing of this offering; and

• no exercise of the underwriters’ over-allotment option.

As noted above, our estimated minimum distributions from WES are based on an assumption that WES will pay a distribution of $0.52 per unit with respect to each quarter during the year ending December 31, 2013. We believe that this minimum distribution from WES is achievable because, in connection with its third quarter earnings announcement, WES:

• reaffirmed its distribution growth guidance of 16-20% for the full year 2012. In order to achieve this distribution growth in 2012, it is anticipated that WES will raise its distribution with respect to the fourth quarter of 2012 to $0.52 per unit; and

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• announced that it expects to raise its quarterly distribution by a minimum of 15% in 2013, which implies that it expects to raise its quarterly distribution by an average of $0.02 per quarter in 2013, consistent with WES’s $0.02 increases in its quarterly distribution in each of the last four quarters.

We further believe that it is reasonable to expect WES to achieve the financial performance necessary to generate the estimated minimum necessary Adjusted EBITDA and deliver the expected distribution growth due to the following:

• WES’s largest asset position is in the DJ Basin in Colorado, where Anadarko has announced rates of return of over 100% on wells drilled and an increase in its rig count from seven to ten rigs in the second half of 2012;

• WES’s third cryogenic train at Chipeta was completed in October 2012;

• WES’s trailing twelve month Adjusted EBITDA reflects the impact of its recently acquired additional 24% interest in Chipeta only from August 1, 2012, whereas its 2013 operating results will include this additional interest for the full year;

• WES has announced that it expects its Brasada plant will become operational in the second quarter of 2013;

• throughput volumes for the White Cliffs pipeline are expected to increase due to (i) continued robust drilling activity in the Wattenberg Field, (ii) White Cliff’s recently announced binding open season to expand capacity on the White Cliffs Pipeline by approximately 80,000 barrels per day and (iii) White Cliffs’ status as the only pipeline delivering crude oil out of the basin and to the crude oil marketing hub in Cushing, Oklahoma;

• the fixed prices established in WES’s commodity price swap agreements with Anadarko will be higher in 2013 than they were in 2012 with respect to substantially all of WES’s assets;

• given its issuance of $150 million of additional senior notes due 2022 in October 2012, WES anticipates that it will have at least $790 million available for borrowing under its revolving credit facility at the beginning of 2013; and

• since its initial public offering, WES has a consistent track record of executing accretive acquisitions either from Anadarko or third parties.

If the offering price or size is increased, we will use the resulting additional proceeds to purchase additional WES common and general partner units. We believe the excess of estimated available cash of Western Gas Partners, LP over total distributions of Western Gas Partners, LP presented in the table above would equal the amount needed to enable WES to distribute sufficient additional cash to us to permit us to pay the initial quarterly distribution on the common units we would issue in this offering if the offering price or size were increased to yield aggregate gross offering proceeds of approximately $435 million.

If we receive proceeds in this offering of less than the assumed net proceeds of $281.5 million, and as a result we purchase fewer WES common and general partner units, Anadarko will agree to forgo certain distributions (subject to future reimbursement) for the benefit of the other holders of our common units. Please read “Prospectus Summary—Our Structure.”

(9) We estimate that our incremental general and administrative expenses associated with being a publicly traded partnership will not exceed $3.0 million for the year ending December 31, 2013.

(10) The WES RCF contains various customary covenants, including a covenant to maintain a maximum consolidated leverage ratio (which is defined in the WES RCF as the ratio of consolidated indebtedness as of the last day of a fiscal quarter to consolidated earnings before interest, taxes, depreciation and amortization for the most recent four consecutive fiscal quarters ending on such day) of 5.0 to 1.0, or a consolidated leverage ratio of 5.5 to 1.0 with respect to quarters ending in the 270-day period immediately following certain acquisitions. The leverage ratio is calculated using the aforementioned assumptions and should not be interpreted as WES’s projected leverage ratio for the year ending December 31, 2013.

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