According to TMZ, Len filed the paperwork, citing irreconcilable differences.
The documents state both he and Kate, who have no children together, have waived any right to spousal support.
It's believed that an iron-clad prenup is in place from their 2004 nuptials.
This seems to be a long time coming, as the duo was reportedly on the rocks a year ago. There were reports in November of 2015 that Kate and Len "secretly separated" several months prior to that.
Around the same time last year, Len was photographed without his ring while enjoying an evening out with 24-year-old model CJ Franco, whom he'd been photographed with several times before, as well.
"They are still friendly and spend time together in L.A. when Kate is there," a source told People magazine at the time, adding that "there has been no drama."
"It's just not Kate's style," continued the source. "They have both had complicated schedules and have grown apart."
When it appeared that the writing was on the wall for a divorce, a report in The Sun stated that Kate was batting around the idea of trying to reconcile with her ex Ben Affleck, whom she reportedly dated briefly in 2001.
"Kate used to be madly in love with Ben. He would make her giddy with excitement any time they were in the same room," a source told the publication. "She's turned to him for support as a friend because they've stayed in touch during her difficult time."