DexCom stock leads S&P 500’s premarket gainers after denying merger talks, and Insulet stock drops

Shares of DexCom Inc. surged 8.1% to pace the S&P 500’s premarket gainers, after the diabetes care company said it was not currently in “active discussions” regarding a merger. The stock has been dragged down over the past week, closing at a two-year low on Thursday, after Bloomberg reported that DexCom was in talks to buy Insulet Corp. , a maker of insulin-infusion systems. Insulet’s stock sank 10.7% in premarket trading. “It is generally our policy not to comment on rumors or speculation, however, in light of recent sustained media and market speculation as well as the upcoming American Diabetes Association conference, we wish to confirm that Dexcom is not in active discussions regarding a merger transaction at this time,” DexCom said in a statement Tuesday.

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