Credit: Mathew Imaging/

Jennifer Carpenter filed divorce papers from Dexter costar Michael C. Hall on Thursday afternoon -- the same day that Julia Stiles slammed reports that she had an affair with Hall, 39.

Carpenter, 31, cites "irreconcilable differences" in her petition, filed in L.A. County Superior Court. The papers also noted that the couple have been separated since Aug. 9, 2010. She is seeking spousal support.

Reps for Carpenter and Hall announced their "amicable" split on Monday.

"I have absolutely nothing to do with the split between Michael and Jennifer. We are good friends and enjoyed working together," Stiles, 29, told Us in a statement Thursday.

"This is a personal matter between them, and we should respect their privacy. Although I too prefer to keep my private life private, I felt compelled to dispel the rumors I was somehow the cause for this matter."