Phoenix is asking for joint legal and physical custody of their two children, Indiana, 12, and Atticus, 9.
The couple first announced their separation in March of 2016, putting an end to a Hollywood relationship that spanned 16 years.
Affleck and Phoenix wedded in 2006 in the wake of getting to be noticeably occupied with 2003.
So, this means that both Casey and Summer are single now. They share two children together, IN and Atticus. Affleck is the younger brother of actor and director Ben Affleck. They Wednesday in June, 2006 following the birth of their first child.
Casey's representatives have confirmed the news from People about the couple's divorce.
Summer, 38, cited "irreconcilable differences" in her split from the 41-year-old, the reigning Academy Award-winner for best actor after his lauded performance in Manchester By the Sea, E! reports.
The couple met in 1995, after being introduced by Summer's brother, actor Joaquin Phoenix, who worked with Affleck on the film To Die For. Back in 2010, he was sued by two of his former co-workers for more than $2 million.