US STOCKS-M&A activity lifts index futures

* HP offers $24 a share to acquire 3PAR

* Campbell may bid for United Biscuits: report

* 3M CEO says may double acquisition money spent in 2010

* Futures up: Dow 37 pts, S&P 500 5 pts, Nasdaq 11.5 pts

* For up-to-the-minute market news see [STXNEWS/US]

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By Ryan Vlastelica

NEW YORK, Aug 23 (Reuters) - U.S. stock index futures rose on Monday, following two weeks of losses for the S&P and Dow, as sentiment was lifted by several potential mergers and deals.

Hewlett-Packard Co bid $24 a share in cash for data storage company 3PAR Inc , sending the stock up 37 percent to $24.70 in premarket trading. HP, a Dow component, fell 1 percent to $39.45. For details see [ID:nN23188685]

Campbell Soup Co may make a $2.3 billion break-up bid for Britain's United Biscuits, which is owned by private equity firms PAI Partners and Blackstone Group LP , according to the London-based Sunday Times. [ID:nLDE67L05L]

And George Buckley, the chief executive of 3M Co , said the Dow component may spend about $2 billion on acquisitions in 2010, twice its previous estimate. [ID:nTOE67M07U]

"All this M&A activity is a sign of confidence that the situation out there has a silver lining about it," said Andre Bakhos, director of market analytics at Lek Securities in New York.

"Nothing seems to be of heavy impact, but these things are all adding up."

Last week Intel Corp moved to acquire software maker McAfee Inc for $7.7 billion. [ID:nN19252526]

S&P 500 futures rose 5.6 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures rose 37 points, and Nasdaq 100 futures rose 11.5 points.

Concerns about the strength of the recovery have intensified in recent weeks, with weak economic data adding to the cautious tone and depressing trading volume levels.

A $20 billion compensation fund for economic victims of the BP Plc Gulf oil spill opens for business on Monday amid accusations that the rules established by its administrator are unfair. U.S.-listed shares of BP slid 1 percent to $36.03 in premarket trading. [ID:nN22130561]

October crude futures edged slightly higher to $74.12 per barrel, though prices were close to last week's six-week lows on bulging inventories. [ID:nSGE67M035]

The Federal Reserve plans to reduce American International Group Inc's credit line by about $3.6 billion in a sign of growing confidence that the government bailed-out insurer can emerge from taxpayer support, Bloomberg said, citing a person with knowledge of the proposal.

U.S. stocks slipped on Friday and the S&P 500 and Dow fell for a second straight week on persistent concerns the recovery has tapered off. For the week, the S&P 500 was down 0.7 percent and the Dow slipped 0.9 percent, while the Nasdaq gained 0.3 percent on some positive outlooks in technology shares.

(Editing by Padraic Cassidy) ((ryan.vlastelica@thomsonreuters.com; Tel: +1 646-223-6014; Reuters Messaging: ryan.vlastelica@reuters.com@reuters.net))