A person familiar with the deal says the extension is worth $80 million. The person spoke to The Associated Press on condition of anonymity Monday because the team doesn't release financial terms of contracts.
Carolina had placed the franchise tag on the 6-foot-3, 315-pound Short earlier this offseason.
The 28-year-old Short has started 41 games in four seasons with the Panthers, including 32 in the past two seasons.
He had 55 tackles in each of the past two seasons, and combined for 17 sacks - 11 of those coming in 2015 when he helped the Panthers reach the Super Bowl.
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