Portsmouth have released 10 players, including midfielders Richard Hughes and Michael Brown.
Goalkeeper Darryl Flahavan and striker Danny Webber have also been let go.
Youngsters Marlon Pack, Pete Gregory, Tom Kilbey, Perry Ryan, Ellis Martin and Billy Goddard will not be offered new deals and will leave the club.
Hughes, 31, made 165 appearances for Pompey following his 2002 switch from Bournemouth. His final appearance was against Leeds on 28 December.
The duo agreed the clauses when Pompey were in the Premier League and were unwilling to accept new terms from the club.
Former Southend keeper Flahavan, 32, failed to make an appearance for the club since his summer switch.
Ex-Sheffield United man Webber, 29, joined Portsmouth in 2009 but made just five league starts, featuring mostly from the bench.
Pack, 20, made just two substitute appearances for the club in August before spending the rest of the season on loan at Cheltenham.
Ryan, Martin and Goddard never played for the first team.