New York (AFP) - The S&P 500 topped the 2,000 mark for the first time during trade Monday but slipped back to finish just below the benchmark.
Stocks were broadly higher in confident buying during the session, bolstered by the Federal Reserve's caution over raising rates and a handful of new merger deals.
The broad-market S&P 500 index gained 9.52 points (0.48 percent) at 1,997.92. The intraday peak, a record, was 2,001.95.
The narrower blue chip Dow Jones Industrial Average rose 75.65 points (0.44 percent) to 17,076.87, while the tech-rich Nasdaq Composite added 18.80 (0.41 percent) to 4,557.35, its highest level since the dot-com crash 14 years ago.
Analysts said the markets were helped by Federal Reserve chief Janet Yellen's commitment Friday to keeping interest rates low despite warnings from a growing minority of so-called inflation hawks.
Fresh takeover news also bolstered buying. Pharmaceutical company InterMune, with a treatment for the deadly lung affliction pulmonary fibrosis, surged 35.4 percent to $72.85 after Swiss giant Roche announced a $74 a share buyout, worth $8.3 billion in total.
Burger King and Canadian fast-food chain Tim Hortons confirmed reports that they were weighing a tie-up that would aim to move Burger King's headquarters from the United States to Canada to take advantage of lower corporate tax rates.
Burger King shares gained 19.5 percent while Tim Hortons, traded on the Toronto exchange, added 19.3 percent.
Also reported during trading hours, and confirmed after the market closed, was Amazon's nearly $1 billion purchase of videogame streaming website Twitch. Amazon added 0.7 percent, while Google, which had earlier pursued Twitch, lost 0.4 percent.
Netflix finished up 0.4 percent.
Goldman Sachs rose 1.4 percent after last Friday's late announcement of a deal with the Federal Housing Finance Agency to settle allegations it sold misrepresented mortgage bonds to Fannie Mae and Freddie Mac ahead of the financial crisis.
Goldman is buying back $3.15 billion of the bonds, with the penalty accruing to it estimated only at $1.2 billion, the difference between the market value of the bonds and what it is paying the FHFA.
Bond prices were higher. The yield on the 10-year US Treasury fell to 2.38 percent from 2.40 percent late Friday, while the 30-year dropped to 3.13 percent from 3.16 percent. Bond prices and yields move inversely.