* FTSEurofirst 300 down 0.4 pct
* Nutreco, Adidas, Havas surge on M&A activity
By Blaise Robinson
PARIS, Oct 20 (Reuters) - European stocks fell early on Monday, trimming lofty gains made in the previous session, with SAP's profit warning hitting shares in the tech sector.
Shares in the German business software maker plunged 4.6 percent after it cut its outlook for full-year operating profit, echoing a raft of profit and sales warnings from other tech groups in the past few weeks.
The market's losses were limited, however, by brisk M&A activity, boosting the shares of Nutreco, Adidas and Havas.
Shares in Dutch animal feed and nutrition company Nutreco soared 39 percent after SHV, a privately held Dutch investment firm, said it had reached a conditional agreement to acquire the group for 40 euros ($51) per share, or 2.69 billion euros.
German sportswear firm Adidas AG surged 5.6 percent after the Wall Street Journal reported that an investor group, that includes Jynwel Capital and funds affiliated with the Abu Dhabi government, was planning a $2.2 billion bid to buy Adidas unit Reebok.
Havas also rose, by 5.8 percent, after French tycoon Vincent Bollore launched an exchange offer on the stock on Friday with a view to gaining control of the world's sixth-largest advertising company. Shares in Groupe Bollore dropped 6.9 percent.
At 0751 GMT, the FTSEurofirst 300 index of top European shares was down 0.4 percent at 1,275.56 points, trimming sharp gains made on Friday when the index surged 2.8 percent following reassuring U.S. macroeconomic data. The data halted a previous sell-off in European shares.
"Calm returns after last week's roller-coaster ride," Saxo Bank trader Andrea Tueni said.
"U.S. macro data is reassuring, the earnings season has been quite good so far, and we're getting positive news such as Japan's big pension fund boosting its exposure to equities. Sentiment remains fragile, but we get the impression that stocks have hit a low."
Japan's $1.2 trillion public pension fund, the world's largest, is likely to raise its allocation for domestic stocks to about 25 percent, people familiar with the process said on Saturday. The news helped shares in Tokyo surge 4 percent on Monday.
On the European earnings front, shares in Electrolux rose 4.8 percent after the global home appliances maker reported forecast-beating quarterly profits.
Europe bourses in 2014: link.reuters.com/pap87v
Asset performance in 2014: link.reuters.com/gap87v
Today's European research round-up
Editing by Susan Fenton