Martin Castrogiovanni has joined European champions Toulon from English side Leicester, the two clubs said on Friday.
Chiliboy Ralepelle has turned down a new offer from the Bulls and has opted to continue his career with Top 14 side Toulouse.
Heineken Cup champions Toulon avoided the continent's big guns when they were paired with Cardiff Blues, Glasgow and Exeter.
Clermont boss Vern Cotter will remain at the Top 14 club next season and take up his role as Scotland head coach in June 2014.
Wynand Olivier will be released early from his contract with the Bulls to take up a one-year deal with Top 14 side Montpellier.
Castres clinched their first French title in 20 years when they upset Toulon 19-14 in the Top 14 final at the Stade de France.
Montpellier have confirmed 12 new recruits for next season's Top 14 campaign.
Incoming Scotland coach Vern Cotter has denied offering to resign his post at Clermont Auvergne one year ahead of schedule.
New Zealander Vern Cotter has been confirmed as the next head coach of Scotland - but will not take charge until next summer.
Castres stunned this season's table-toppers Clermont with a 25-9 victory to make the Top 14 final.
Jonny Wilkinson continued his rich vein of form as Toulon crushed Toulouse 24-9 in Nantes to reach the Top 14 final.
Ireland's most capped player Ronan O'Gara has retired to take up a role coaching former rival Jonathan Sexton at Racing Metro.
Castres outplayed Montpellier to make the semi-finals of the Top 14 with a 25-12 home victory.
South Africa fly-half Morne Steyn is to join Stade Francais on a three-year deal, the French Top 14 club said on Tuesday.
Clermont Auvergne notched up a record 60th win in succession at home when defeating Bordeaux-Begles 67-3.
Australia winger Digby Ioane is to leave the Queensland Reds and move to a French club at the end of the Super Rugby season.