MarkWest Energy Partners, L.P. (NYSE: MWE) today announced that the Board of Directors of the General Partner of MarkWest Energy Partners, L.P., declared a cash distribution of $0.84 per common unit for the second quarter of 2013, for an implied annual rate of $3.36 per common unit. The second quarter 2013 distribution represents an increase of $0.04 per common unit, or 5.0 percent, compared to the second quarter 2012 distribution and an increase of $0.01 per common unit, or 1.2 percent, compared to the first quarter 2013 distribution. The second quarter 2013 distribution is payable August 14, 2013, to unitholders of record on August 6, 2013. The ex-dividend date is August 2, 2013. MarkWest Energy Partners, L.P. is a master limited partnership engaged in the gathering, processing and transportation of natural gas; the gathering, transportation, fractionation, storage and marketing of natural gas liquids; and the gathering and transportation of crude oil. MarkWest has a leading presence in many unconventional gas plays including the Marcellus Shale, Utica Shale, Huron/Berea Shale, Haynesville Shale, Woodford Shale and Granite Wash formation. This press release is intended to be a qualified notice under Treasury Regulation Section 1.1446-4(b). Brokers and nominees should treat one hundred percent (100.0%) of MarkWest’s distributions to non-U.S. investors as being attributable to income that is effectively connected with a United States trade or business. Accordingly, MarkWest’s distributions to non-U.S. investors are subject to federal income tax withholding at the highest applicable effective tax rate. This press release includes “forward-looking statements.” All statements other than statements of historical facts included or incorporated herein may constitute forward-looking statements. Actual results could vary significantly from those expressed or implied in such statements and are subject to a number of risks and uncertainties. Although MarkWest believes that the expectations reflected in the forward-looking statements are reasonable, MarkWest can give no assurance that such expectations will prove to be correct. The forward-looking statements involve risks and uncertainties that affect operations, financial performance, and other factors as discussed in filings with the Securities and Exchange Commission (SEC). Among the factors that could cause results to differ materially are those risks discussed in the periodic reports filed with the SEC, including MarkWest’s Annual Report on Form 10-K for the year ended December 31, 2012 and our Quarterly Report on Form 10-Q for the quarter ended March 31, 2013. You are urged to carefully review and consider the cautionary statements and other disclosures made in those filings, specifically those under the heading “Risk Factors.” MarkWest does not undertake any duty to update any forward-looking statement except as required by law.