The megahit AMC series “The Walking Dead” continues to be the focal point of a heated legal battle between the cable channel and the show’s developer, Frank Darabont. Variety reports that Darabont “doubled down Thursday on his claim that AMC cheated him out of millions of dollars in ‘Walking Dead’ profits, filing a new lawsuit alleging that he is owed additional tens of millions of dollars.”

The war between Darabont and AMC has been going on for more than four years, with Darabont and his agency, CAA, accusing the channel of depriving them of $280 million by “failing to engage in arm’s length transactions for distribution of the show,” Variety reports.

“In the new lawsuit, filed Thursday in New York Supreme Court, Darabont alleges that new information shows that he is entitled to tens of millions in additional compensation,” Variety adds. “Darabont’s attorneys contend that he is entitled to ‘most favored nation’ treatment with respect to how his profit participation is calculated. But until recently, his lawyers were unaware that another producer on the show, Robert Kirkman, had a profit calculation based on AMC’s ‘actual’ distribution fee, rather than an ‘imputed’ fee used in Darabont’s case. Since Kirkman received a more generous agreement, Darabont alleges his contract is entitled to the same treatment.”