Cigna shares popped 11% in trading on Monday morning following a Wall Street Journal report that said Anthem has approached it for a merger.
Anthem shares rallied by more than 2% on the news.
If the deal comes through, it would be one of several we've seen this year in the healthcare industry.
The two companies have been in talks for several months and Anthem has made two offers, according to the Journal. The latest is for about $175 a share, the Journal reported.
Here's a chart showing the surge in Cigna shares, which are up about 67% over the past 12 months:
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