U.S. stocks futures pointed to a flat open on Monday after data showed manufacturing activity in New York State grew at a slower pace than expected, offsetting optimism on the back of a flurry of mergers.

Investors questioned the ability of the U.S. recovery to blunt concerns over the impact of heavy euro-zone debt loads on a global level.

The New York Federal Reserve's gauge of manufacturing in New York State continued to grow in May but at a slower pace and came in far below forecasts.

This is just confirmation that the recovery is not exactly robust. Yes, we have a recovery, but everyone sees the recovery as basically more of a stabilization than a new growth trend, said Peter Kenny, managing director at Knight Equity Markets in Jersey City, New Jersey.

It's a tug of war between macro U.S. and global. Is the U.S. leadership in the economic rebound going to be strong enough to overcome the perilous decline of the euro?

S&P 500 futures shed 1.2 points and were slightly 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 dropped 16 points, and Nasdaq 100 futures fell 4 points.

Futures rose early Monday as a slew of mergers and acquisitions pointed to continued strength in the U.S. recovery.

Hospital operator Universal Health Services Inc said it would buy Psychiatric Solutions Inc , which operates mental health facilities, for about $2 billion in cash plus the assumption of about $1.1 billion in debt.

Psychiatric Solutions shed 0.3 percent to $32.52 in premarket trade, while Universal Health jumped 7.8 percent to $42.10.

Astellas Pharma Inc <4503.T>, Japan's No.2 drugmaker, agreed to buy U.S. biotech OSI Pharmaceuticals Inc for $4 billion in cash in a sweetened bid that would add OSI's blockbuster cancer drug Tarceva to its line-up. OSI shares shed 4.1 percent to $57.34.

GLG Partners Inc surged 51 percent to $4.39 after it agreed to be acquired by rival hedge fund firm Man Group PLC .

And private equity firm Apollo Global Management is in talks to buy U.S. packaging maker Pactiv Corp , the Wall Street Journal reported, citing sources. Pactiv shares jumped 21 percent to $29.

Home improvement chain Lowe's Cos Inc , considered an indicator on the strength of the housing market, slipped 3.7 percent to $25.11 premarket after reporting higher-than-expected quarterly profit, but forecast second-quarter earnings below estimates.

The National Association of Home Builders/Wells Fargo May housing market index will be reported later Monday.

(Reporting by Chuck Mikolajczak; editing by Jeffrey Benkoe)