My favorite sport is basketball
No problem. So technically speaking coaches who remain under contract still need permission from their previous teams in order to be on a new team. The team who holds the contracts can get compensation for a coach "trade". So Doc Rivers could actually be sent to the Clippers in that pipe dream of a trade that could only have been thought up by Stephen A smith.
only once. SVG to the Magic. he was still under contract with the Heat. They received a 2nd rounder as compensation
"ESPN SportsCenter reported that the Heat allowed Van Gundy to coach the Magic in exchange for a second-round draft pick in 2007 and the right to swap first-round picks in 2008 or another 2008 second-round draft pick and cash.