(CNBC) — U.S. equities closed slightly higher on Monday, but a decline in General Electric shares, coupled with worries about tax reform, capped gains in the major indexes.

The S&P 500 rose 0.1 percent, with Mattel shares surging 20 percent on news that Hasbro has approached the toy maker about a takeover. Hasbro’s bid for Mattel is the latest news out of a dealmaking space that has recently picked up steam. Last week, CNBC learned that 21st Century Fox has been in talks to sell most of the company to Disney. Also, Qualcomm rejected a $105 billion bid from Broadcom.

GE, meanwhile, was the worst-performing stock in the S&P 500. It fell 7.2 percent after the company issued weaker-than-expected guidance for 2018. The industrial giant also slashed its dividend by 50 percent and announced it will focus on its health care, aviation and energy businesses moving forward.

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