What are the duties that an in-house counsel owes to her company once she leaves for a new job? That’s the question Schlumberger Ltd. is raising in a new motion to disqualify a plaintiff’s inside and outside counsel in a federal patent case.

The motion raises serious ethical and confidentiality issues around the work of Charlotte Rutherford, Schlumberger’s former deputy general counsel for intellectual property. Rutherford left to take a job as senior vice president of Acacia Research Group, a Houston-based patent licensing company, in June of last year.