Portsmouth Football Club have taken up options to extend the deals of Marcus Harness, Louis Thompson, Jay Mingi and Jayden Reid.
Alex Bass, Ronan Curtis, Kieron Freeman, Denver Hume, Haji Mnoga, Joe Morrell, Connor Ogilvie, Clark Robertson, Ryan Tunnicliffe and Liam Vincent all remain under contract.
First year professional deals for Harry Jewitt-White and Toby Steward, as well as third year scholarships for Alfie Bridgman and Dan Gifford, have already been announced.
The club remain in negotiations with Reeco Hackett, Michael Jacobs, Aiden O’Brien and Sean Raggett regarding new contracts.
Pompey can also confirm that four players will be leaving when their contracts expire this summer.
Paul Downing, Callum Johnson, Ollie Webber and Shaun Williams are all departing Fratton Park.
Central defender Downing signed in the summer of 2019 and made 27 appearances for the Blues, spending the second half of last season on loan at Rochdale.
Right-back Johnson joined from Accrington a year later and featured 48 times, but spent the majority of last term with Fleetwood.
"It happens at the end of every season and is part of football, but it is always difficult to say goodbye to players."
Republic of Ireland international Williams played 35 matches in his sole campaign on the south coast.
Goalkeeper Webber made the switch from Crystal Palace in January and served as back-up to Gavin Bazunu.
Bazunu, Hayden Carter, George Hirst, Mahlon Romeo and Tyler Walker have returned to their parent clubs and we would like to thank Manchester City, Blackburn, Leicester, Millwall and Coventry.
Pompey would also like to thank all those departing players for their service to the club and wish them well for the future.
Blues boss Danny Cowley said: “It happens at the end of every season and is part of football, but it is always difficult to say goodbye to players.
“It doesn’t matter whether they were contracted to us or loanees who made such a big contribution to our season – we know they will go on to further success, but it’s sad when our journey comes to an end.
“We would like to thank them all for their service and professionalism during their time at this football club.
“We wish all the players nothing but the very best wishes in moving forward with their careers and look forward to watching their progress.”