Seyfarth Shaw probably wishes it had never heard of Billy Blanks.

In the latest development involving its former representation of the Tae Bo creator, a Seyfarth Shaw partner has sued his own firm. The lawsuit, brought by nonequity partner William Lancaster, alleges that Seyfarth Shaw demoted and exploited him for his role in representing Blanks, who won a $30 million malpractice verdict against the firm.