UPDATE 1-MarkWest shareholder opposes acquisition by Marathon Petroleum

(Adds details from letter, background)
Nov 4 (Reuters) - A unitholder in natural gas processor
MarkWest Energy Partners LP MWE.N , John Fox, came out in
opposition to a proposed $15.6 billion takeover by Marathon
Petroleum Corp MPC.N , saying it would lead to a big cut in
cash distributions to unitholders.
Fox, who has a 0.7 percent stake in MarkWest, said MarkWest
should remain a standalone company.
Marathon plans to buy MarkWest in a cash-and-stock deal
through its pipeline master limited partnership (MLP), MPLX LP
MPLX.N . urn:newsml:reuters.com:*:nPnbS1Sqt
The deal would reduce distributions by 46 percent and the
cash being paid by MPLX would not adequately make up for losses
incurred by MarkWest investors, Fox said in an open letter to
the board of MarkWest Energy GP LLC, MarkWest's general partner.
The directors and executive officers of MarkWest Energy GP
own about 0.8 percent of MarkWest Energy Partners.
MPLX has offered 1.09 of its units and $3.37 in cash per
MarkWest unit, which translated to about $78.64 per unit when
the offer was made on July 13. urn:newsml:reuters.com:*:nL4N0ZT3S9
MarkWest closed at $46.51 on Tuesday.
Since MPLX is required to make incentivized distribution
rights payments to Marathon, that would reduce the amount of
cash available for MarkWest Energy unitholders, Fox said.
Fox said MarkWest Energy had "a tremendous growth platform"
given its assets across the country, including those in Ohio's
Utica shale region and Pennsylvania's Marcellus shale deposits,
as well as 4,000 miles of pipelines.
"Why would you give away, for pennies on the dollar, this
marvelous company you have built and all its future growth
potential?" Fox said in the letter released on Wednesday.
The MarkWest-MPLX deal comes at a time when MLPs have lost
favor among investors as the tax-advantages linked to these
structures become less attractive due to a steep plunge in oil
prices that has hit profits in the oil industry.
The acquisition, which will create the fourth-largest MLP,
is expected to close in the fourth quarter.