Shares of Insulet Corp. gained 9.9% in premarket trading on Tuesday, the day after Bloomberg reported that the company is in talks to be acquired by Dexcom Inc. , citing anonymous sources. Dexcom’s stock was down 7.1% before the market opened on Tuesday. A tie-up between the companies would create a major player in the diabetes sector. Dexcom manufactures continuous glucose monitoring systems, while Insulet makes a disposable insulin delivery system. Insulet CEO Shacey Petrovic announced earlier this month that she’s stepping down June 1 for family reasons. Insulet’s stock is down 23.7% this year, while the broader S&P 500 has slid 18.1%.

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