London Welsh have released New Zealand scrum-half Tyson Keats as they prepare for their Premiership return.
Keats was involved in a visa-related ineligibility row in 2013, resulting in a five-point deduction and ultimately relegation for the Exiles.
Keates, 33, is one of 25 let go, along with ex-Wales centre Sonny Parker, 36, and 33-year-old prop Peter Edwards.
Chris Cook and Will Spencer, who played in the Championship play-off final against Bristol, are returning to Bath.
Hooker Nathan Morris, who scored two tries in 22 appearances last season, goes back to London Wasps after completing his loan spell.
The Exiles have released props Tom Bristow, Cai Griffiths, Alec Hepburn, Billy Moss, Paddy Ryan and James Tideswell, while wingers Joe Ajuwa, Liam O'Neill and Josh Watkins are all looking for new clubs.
Scrum-half Ollie Frost, stand-off Toby L'Estrange and centre Hudson Tonga'uiha have also been told they can leave, along with forwards Mike Denbee, John Quill, Rob Andrew, Kevin Davis and Ian Nimmo.