July 12 (Reuters) - Top U.S. independent oil producer

ConocoPhillips ( COP ) said on Friday it received a second

request from the U.S. Federal Trade Commission for information

on its proposed acquisition of rival Marathon Oil ( MRO ).

ConocoPhillips ( COP ) said both companies received the requests on

July 11 and are working with the FTC to review the merger.

CONTEXT

Conoco said in May it would pay $22.5 billion in stock for

Marathon Oil ( MRO ) to boost its output and achieve greater economies

of scale in U.S. shale fields and in liquefied natural gas.

Its deal followed Exxon Mobil's ( XOM ) $60 billion

acquisition of Pioneer Natural Resources, Chevron's ( CVX )

proposed $53 billion merger with Hess, Chesapeake Energy's ( CHK )

$7.4 billion purchase of Southwestern Energy and

Occidental Petroleum's ( OXY ) $12 billion bid for CrownRock.

WHY IT'S IMPORTANT

The request for additional information is likely to slow the

closing of the deal. ConocoPhillips ( COP ) had said in May a

"conservative" estimate of when the deal will close is the

fourth quarter of this year, putting off a full realization of

the expected cost savings and benefits from shared equipment and

staff. It reiterated the timeframe on Friday.

The two companies have operations in West Texas, South Texas

and North Dakota's shale fields.

BY THE NUMBERS

The Conoco-Marathon combination would create a company

pumping 2.26 million barrels of oil and gas per day, and add

1.32 billion barrels of proved reserves to ConocoPhillips' ( COP ) 6.8

billion.

The offer of 0.255 shares of ConocoPhillips ( COP ) for each share

of Marathon represented a 14.7% premium to the company's

pre-deal closing price.