* Investors looking ahead to bellwether company earnings
* Merck up after FDA review, strategic options plans
* Lululemon, Sodastream, Express fall after outlooks
* Indexes down: Dow 0.4 pct, S&P 0.4 pct, Nasdaq 0.3 pct
By Ryan Vlastelica
NEW YORK, Jan 13 (Reuters) - U.S. stocks fell on Monday as investors awaited an onslaught of corporate results to gauge how companies are faring amid mixed signs on economic growth.
While some early reads on the season have been positive, market participants are looking for further justification that stocks are fairly valued with indexes near all-time highs.
Following a jump of almost 30 percent last year, the S&P 500's forward price-to-earnings ratio is the highest in nearly seven years. While fourth-quarter earnings are seen rising 7.3 percent, according to Thomson Reuters data, the 9.8 ratio of negative to positive guidance is at a record.
"People are sitting on their hands, waiting for major results to figure out how strong this season may be," said Douglas DePietro, managing director at Evercore Partners in New York.
DePietro was looking forward to results from JPMorgan Chase & Co and Wells Fargo & Co, both slated to report on Tuesday. General Electric Co, Goldman Sachs and Intel Corp are also reporting this week.
Equity gains have largely come on accommodative monetary policies by the Federal Reserve, although not all economic indicators enjoyed a similar boost. The December payroll report, released on Friday, came in much lower than expected.
The Dow Jones industrial average was down 67.72 points, or 0.41 percent, at 16,369.33. The Standard & Poor's 500 Index was down 7.55 points, or 0.41 percent, at 1,834.82. The Nasdaq Composite Index was down 12.93 points, or 0.31 percent, at 4,161.74.
Losses were limited in the Dow and S&P by Merck & Co , which rose 2.9 percent to $51.33, after a preliminary U.S. Food and Drug Administration review said the company's experimental blood clot-preventing drug vorapaxar should be approved.
The drugmaker also said it is pursuing strategic options for its animal health and consumer businesses and expects to complete any action it takes this year.
Equities have started 2014 on a lackluster note, dipping 0.7 percent year-to-date as market participants tried to gauge how quickly the Fed will wind down its stimulus.
In merger news, Beam Inc agreed to be acquired by Suntory Holdings Ltd for $16 billion, including debt, while British engineering firm Amec provisionally agreed to buy Foster Wheeler in a cash and share deal that values the company at $3.13 billion. Shares of Beam jumped 24 percent to $83.16 while Foster Wheeler rose 1.3 percent to $31.86.
"Merger and acquisition activity continues to be an underlying bullish sentiment for the market," said DePietro. "It's one of the most positive things reflecting on the market."
On the downside, Scripps Networks Interactive Inc fell 5.4 percent to $77.61 after the Wall Street Journal reported that the company had abandoned talks for a merger with Discovery Communications Inc last week. Discovery fell 1.7 percent to $82.62.
Lululemon Athletica Inc, Express Inc and Sodastream International all fell after giving weak fourth-quarter outlooks. Lululemon sank 16 percent to $50.21 while Express slid 2.6 percent to $18.2 and Sodastream plunged 22 percent to $38.80.
But Wendy's outlook was a bright spot, sending shares up 8.3 percent to $9.14 after the fast-food restaurant chain estimated adjusted quarterly earnings above analysts' expectations, as expenses fell due to franchising many company-owned outlets.