Seferian-Jenkins, who joined the Jaguars on a two-year deal in 2018, will become an unrestricted free agent.
The 32-year-old Campbell headlines the returning players, and he enjoyed his second consecutive Pro Bowl season. He joined the Jaguars in 2017 after spending nine seasons with the Arizona Cardinals and produced 25 sacks over the past two campaigns. NFL Network's Tom Pelissero reports Campbell's option is for $3 million.
McCray and Davis have mostly made their mark in Jacksonville as core special team contributors. Davis led the Jaguars with 10 special teams tackles in 2018.
Seferian-Jenkins, 26, will now search for his fourth team since entering the league in 2014 as a second-round pick with the Tampa Bay Buccaneers. The tight end started five games in 2018 before missing the final 11 games with a core muscle injury.