"[It's] completely false," Thornton, 61, told TMZ on Tuesday, August 16.
Thornton and Heard, 30, worked together in the 2015 film London Fields. Thornton, however, told TMZ that the two only socialized off set during a cast dinner and have not remained friends or in touch since the project wrapped.
The Bad Santa 2 actor has been married to his sixth wife, Connie Angland, since 2014. (The couple welcomed daughter Bella, in 2004.) Thornton was famously married to Angelina Jolie, pre–Brad Pitt, from 2000 to 2003.
As previously reported, Depp, 53, allegedly cut off the tip of his finger after he accused Heard of cheating with Thornton. According to TMZ, he reportedly injured himself while smashing glass bottles and windows and used his blood to finger paint "Billy Bob" and "Easy Amber" on a bathroom mirror.
"There is no way Amber had any kind of relationship with Billy Bob Thornton," an insider told Us Weekly on Monday.
Heard and Depp continue to be at odds since the actress filed for divorce in May and alleged that he physically harmed her. The two recently had a deposition in their divorce case in L.A. on Saturday, one day after Heard missed the initial hearing. She previously showed up late to a meeting on August 6.
"Johnny wants to settle, and they are working on a settlement. But Amber showed up 90 minutes late for her deposition and then refused to give her deposition. [She's] delaying this because she wants more money," a source told Us at the time.
A Heard source countered the argument. "Although Amber was ready, willing and able to go forward with her deposition, it was not taken by Johnny’s attorneys," a second insider said.
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