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

Date of Report (Date of earliest event reported) October 26, 2007

MARKWEST ENERGY PARTNERS, L.P.

(Exact name of registrant as specified in its charter)

Delaware	001-31239	27-0005456
(State or other jurisdiction of incorporation or organization)	(Commission File Number)	(I.R.S. Employer Identification Number)

1515 Arapahoe Street, Tower 2, Suite 700, Denver CO 80202
(Address of principal executive offices)

Registrant’s telephone number, including area code: 303-925-9200

Not Applicable.

(Former name or former address, if changed since last report.)

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 (see General Instruction A.2. below):

x	Written Communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
o	Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
o	Pre-Commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
o	Pre-Commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 1.01 Entry Into a Material Definitive Agreement

On October 26, 2007, MarkWest Energy Partners, L.P. (the “Partnership”) and its general partner, MarkWest Energy GP, L.L.C. (the “General Partner”), entered into Amended and Restated Indemnification Agreements (each, an “Amended Indemnification Agreement”) with the directors and officers (each, an “Indemnitee”) of the General Partner.

Amended Indemnification Agreements were entered into with all directors and officers of the General Partner, including the following named executive officers: Frank Semple, President and Chief Executive Officer; Nancy Buese, Senior Vice President and Chief Financial Officer; Randy Nickerson, Senior Vice President and Chief Commercial Officer; John Mollenkopf, Senior Vice President and Chief Operations Officer; and C. Corwin Bromley, Senior Vice President, General Counsel and Secretary. The Amended Indemnification Agreements replaced indemnification agreements (each, an “Original Indemnification Agreement”) that were originally signed on January 25, 2007. The Amended Indemnification Agreements clarified the relationship between the registrant, the General Partner and the Partnership, and brought other terms of the Original Indemnification Agreements in line with similar agreements in the marketplace.

The form of Amended Indemnification Agreement provides for indemnification to the fullest extent permitted by law in the event the person was, is or becomes a party, witness or other participant in a Claim (as defined in the Amended Indemnification Agreement) by reason of (or arising in part out of) an Indemnification Event (as defined in the form of Amended Indemnification Agreement).

Each Amended Indemnification Agreement is identical in all material respects. The description of the above-referenced Amended Indemnification Agreement does not purport to be complete and is qualified in its entirety by reference to the complete text of the document, which will be filed as an exhibit in our Form 10-K for the year ending December 31, 2006.

Cautionary Statements

This document shall not constitute an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No offering of securities shall be made except by means of a prospectus meeting the requirements of the Securities Act of 1933, as amended.

MarkWest Energy Partners and MarkWest Hydrocarbon will file a joint proxy statement/prospectus and other documents with the Securities and Exchange Commission (the “SEC”) in relation to the merger transaction announced on September 5, 2007. Investors and security holders are urged to read these documents carefully when they become available because they will contain important information regarding MarkWest Energy Partners, MarkWest Hydrocarbon, and the transaction. A definitive joint proxy statement/prospectus will be sent to security holders of MarkWest Energy Partners and MarkWest Hydrocarbon seeking their approval of the transactions contemplated by the redemption and merger agreement. Investors and security holders may obtain a free copy of the joint proxy statement/prospectus (when it is available) and other documents containing information about MarkWest Energy Partners and MarkWest Hydrocarbon, without charge, at the SEC’s website at www.sec.gov. Copies of the joint proxy statement/prospectus and the SEC filings that will be incorporated by reference in the joint proxy statement/prospectus may also be obtained free of charge by directing a request to the entities’ investor relations department at 866-858-0482, or by accessing their website at www.markwest.com.

MarkWest Energy Partners, MarkWest Hydrocarbon, the officers and directors of the general partner of MarkWest Energy Partners, and the officers and directors of MarkWest Hydrocarbon may be

deemed to be participants in the solicitation of proxies from their security holders. Information about these persons can be found in the Annual Report on Form 10-K, as amended, for each of MarkWest Energy Partners and MarkWest Hydrocarbon, as filed with the SEC, and additional information about such persons may be obtained from the joint proxy statement/prospectus when it becomes available.

ITEM 9.01. Financial Statements and Exhibits

(d) Exhibits.

Exhibit No.		Description of Exhibit

10.1		Form of Amended and Restated Indemnification Agreement with the named executive officers dated October 26, 2007.

SIGNATURE

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

	MARKWEST ENERGY PARTNERS, L.P.
		(Registrant)

	By:	MarkWest Energy GP, L.L.C.,
		Its General Partner

Date: November 1, 2007	By:	/s/ NANCY K. BUESE
		Nancy K. Buese
		Senior Vice President and Chief Financial Officer