2009 World Series of Poker Main Event champion Joe Cada (who broke the record for youngest player to ever win the Main Event) revealed earlier this month that he and PokerStars have gone their "separate ways."
F5poker editor Jeff Walsh has also confirmed that the Netherlands' Marsel Luske and Alex Kravchenko of the Russian Federation are also no longer sponsored pros with the site.
According to a conversation that WSOP's Seth Palansky had with Michael Gentile of pokerfuse.com, the WSOP has a "Gold Club" in the works that could potentially offer more opportunities for former Main Event winners. 2012 WSOP Main Event winner Greg Merson was recently confirmed as an official sponsored pro for regulated U.S. site WSOP.com.
It has been somewhat of a bloodbath in recent months as poker sites have dropped several well-known sponsored pros, including PokerStars releasing Humberto "The Shark" Brenes and Dale "Daleroxxu" Philip, the latter which was apparently related to a separate World Cup event in Spain (see PokerNews video interview below).
Ultimate Poker also decreased its sponsored pro roster recently by half; retaining only 2012 Big One for One Drop champion Antonio Esfandiari, RunItUp host Jason "JCarver" Sommerville, along with Me vs. U talents Dan O'Brien and Danielle Andersen.
Joe Cada posted Wednesday precisely why he did not re-sign with PokerStars, saying that he requested 100% rakeback from the site (which he received as part of his former contract) and was denied.
I think what did not help as many professionals (joe cada) is the black friday they are PRO (United States) there is no market, I think it was lost money for pokerstars.