Stock index futures were slightly lower on Monday as investors awaited data on personal spending for a signal the economy can avoid a double-dip recession and after a fresh batch of merger-and-acquisition activity.

M&A will be in focus after France's Sanofi-Aventis disclosed a cash offer of $18.5 billion, or $69 per share, for Genzyme Corp after failing to engage the U.S. biotechnology company in merger talks. Sanofi said it will consider all options to complete the transaction, hinting at a possible hostile takeover.

Shares of Genzyme rose 3.8 percent to $70.19 in premarket trading and U.S.-listed shares of Sanofi added nearly 1 percent to $29.17.

German chipmaker Infineon Technologies AG agreed to sell its wireless unit to Intel Corp for $1.4 billion, enabling the U.S. chipmaker to boost its presence in the smartphone market.

Intel was unchanged at $18.37 in light premarket trade.

Investors are being a tad apprehensive as the market has had a very fickle personality as of late, said Andre Bakhos, director of market analytics at Lek Securities in New York. In addition to the M&A, the market is looking for an extra reason to come off the sidelines.

At 8:30 a.m. EDT July personal income and consumption data as well as core PCE data is due. Wall Street expected consumption to rise 0.3 percent versus no change in June.

Any data showing an increase in economic activity would help stave off any recessionary themes playing out in the market, added Bakhos.

Dell Inc said it is assessing a bid for data storage company 3PAR Inc

after 3PAR's board said late Friday that Hewlett-Packard Co's $2 billion offer was a superior proposal.

S&P 500 futures were down 1 point and slightly below 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 slipped 20 points, and Nasdaq 100 futures lost 1 point.

European shares ticked higher early Monday, extending a rally to a third day after reassurances the U.S. Federal Reserve was ready to take further steps to spur economic recovery.

In Asia, Japanese shares ended 1.8 percent higher but gave up strong early gains after the Bank of Japan made only minor tweaks in policy, disappointing markets looking for more aggressive action against deflation.

Stocks rebounded to post their best gains in nearly four weeks on Friday, overcoming initial skittishness brought on by a revenue warning from Intel and after Fed Chairman Ben Bernanke said the economic recovery had weakened more than expected.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)