* Earnings season begins this week
* NPS Pharma climbs; to be acquired by Shire
* Foundation Medicine jumps; Roche to take majority stake
* Indexes off: Dow 0.49 pct, S&P 0.55 pct, Nasdaq 0.41 pct (Updates to market open)
By Chuck Mikolajczak
NEW YORK, Jan 12 (Reuters) - U.S. stocks fell on Monday, extending a two-week decline for equities, as weakness in oil prices weighed on the energy sector ahead of the start of corporate earnings season.
Oil prices continued their downward march and weighed on equities, with both Brent and U.S. crude down about 4 percent as Goldman Sachs slashed its short-term price forecasts and Gulf producers showed no signs of curbing output. The S&P energy index was down more than 2 percent.
"During this cycle, since the beginning of the precipitous selloff in the commodity price, we have seen very few days where you would have a three percent move in crude and see stock prices hold onto gains," said Art Hogan, chief market strategist at Wunderlich Securities in New York.
"Investors have a lot of other things to think about, like the pace of Fed tightening, a Greek exit, the possibility of quantitative easing coming from the ECB, but in reality, we are either going to focus on energy prices or earnings will kick in and they will shift their focus to fundamentals."
U.S. stocks fell on Friday after the December jobs report painted a mixed picture of the economy and led the benchmark S&P index to its second straight weekly decline. Since hitting a record high on Dec. 29, the index has fallen 2.2 percent on concerns about global growth, the potential for an exit by Greece from the euro zone and falling oil prices.
Fourth-quarter earnings are expected to grow by 4 percent over the year-ago period, according to Thomson Reuters data.
Alcoa is scheduled to post quarterly earnings after the closing bell, with financials JPMorgan Chase, Wells Fargo, Goldman Sachs and Citigroup due to report later in the week. Dow component Intel Corp is expected to post earnings on Thursday.
The Dow Jones industrial average fell 87.28 points, or 0.49 percent, to 17,650.09, the S&P 500 lost 11.2 points, or 0.55 percent, to 2,033.61 and the Nasdaq Composite dropped 19.36 points, or 0.41 percent, to 4,684.71.
NPS Pharmaceuticals jumped 8.4 percent to $45.44 after Shire Plc agreed to acquire the company for $5.2 billion. U.S.-listed shares of Shire slipped 1.3 percent to $214.60.
Foundation Medicine surged 112.3 percent to $50.81 after Roche Holding agreed to take a majority stake in the company for up to $1.18 billion.
Bristol-Myers Squibb climbed 4 percent to $62.75 as the best performer on the S&P 500 after the company said the independent data monitoring committee concluded a late stage study evaluating its Opdivo lung cancer drug met its endpoint.
Declining issues outnumbered advancing ones on the NYSE by 1,885 to 869, for a 2.17-to-1 ratio; on the Nasdaq, 1,316 issues fell and 894 advanced for a 1.47-to-1 ratio.
The benchmark S&P 500 index was posting 22 new 52-week highs and 15 new lows; the Nasdaq Composite was recording 40 new highs and 34 new lows.
Editing by Bernadette Baum