Image source: Sears Holdings.

Stocks fell sharply on Tuesday, sending the Dow and S&P 500 down roughly half a percent on the day. U.S. investors will remember the nervousness they felt when the Federal Reserve began talking about putting an end to its quantitative easing policies, and today, investors in Europe raised some of the same concerns about the European Central Bank's exit strategy for its own version of the stimulus program. The gold market in particular plunged in response, with the yellow metal dropping $40 per ounce to just above $1,270. Yet some stocks were able to post gains despite the worries, and Endurance Specialty Holdings (ENH), Celldex Therapeutics (CLDX -2.16%), and Sears Holdings (SHLDQ) were among the best performers on a tough day for the market.

Endurance attracts possible buyout interest

Endurance Specialty Holdings soared by more than 35% in the wake of reports from a Japanese news source that the insurance and reinsurance provider was the target of an acquisition by the Japanese unit of Sompo Holdings. The report put the potential value of a deal at $6.5 billion, which would correspond to a per-share price of just under $100. Consolidation in the insurance industry has the benefit of allowing companies to diversify their exposure to various risk markets, spreading out volatility and letting insurers focus on more attractive markets. The report suggests a deal could be finalized by Wednesday, and although today's move upward captures much of any potential rise related to an acquisition, it still leaves some potential profit if the deal ends up being valued at what the report said.

Celldex gets a good review

Celldex Therapeutics climbed 7% after getting positive coverage from analysts at Brean Capital. The biotech company received a buy rating and a price target of $16, which is quadruple where the shares began the day. As Fool biotech analyst Brian Orelli noted earlier today, Celldex is likely to release more results from a key study of its melanoma treatment glembatumumab vedotin within the next week, and that might have spurred Brean's analysts to take a closer look at the stock. Brean based its call on the thesis that glembatumumab vedotin and another drug, CDX-1127, will be able to launch in 2019. Whether that's realistic remains to be seen, but investors certainly took the optimism into account in bidding the stock higher today.

Is Sears looking to sell Craftsman?

Finally, Sears Holdings gained 6%. The stock gain came after reports that it might decide to sell off its Craftsman line of tools and equipment. The department-store chain has gradually divested itself of various assets over a period of years, and Sears had identified Craftsman as one of its key remaining brands, along with Kenmore appliances and Diehard batteries. Investors seem to be increasingly convinced that CEO Eddie Lampert is pursuing asset sales and spinoffs as the final exit strategy for Sears, even though Lampert also said today that it is considering closing its Kmart chain.