The Dow set a record close for the tenth day in a row by climbing 83 points to 14,539 as jobless claims fell. Nasdaq gained 13 points to 3258.
On the upside
Acquisition rumors lifted shares of CommVault Systems (Nasdaq: CVLT).
Dynegy (NYSE: DYN) widened fourth quarter losses but the energy company announced plans to acquire Ameren's (NYSE: AEE) merchant generation business Ameren Energy Resources.
Vipshop (NYSE: VIPS) will raise $96 million through the sale of 4 million American depositary shares at $24 per share.
On the downside
Velti (Nasdaq: VELT) extended its losses after posting an unexpected fourth quarter loss Tuesday after market close and forecasting current quarter results below expectations.
Delcath Systems (Nasdaq: DCTH) disappointed with a loss for the fourth quarter.
U.S. Silica Holdings (NYSE: SLCA) priced its public offering of 8.5 million common shares at the discounted price of $22 per share.
In the broad market, advancing issues outpaced decliners by a margin of more than 2 to 1 on both the NYSE and on Nasdaq. The broader S&P 500 index climbed 8 points to 1563.