By Catherine Fredenburgh (May 16, 2006, 12:00 AM EDT) -- One of the most vexing decisions patent infringement defendants often face is whether to rely on an opinion of counsel to defend against allegations that their infringement is willful. A competent opinion that the asserted patent is invalid and/or not infringed may go a long way toward avoiding a finding of willful infringement and the imposition of trebled damages. However, relying on an attorney opinion waives attorney-client privilege and attorney work-product protections. Accused infringers must therefore carefully weigh the benefits of producing an attorney opinion against the consequences of waiving the privilege when deciding whether to mount an advice-of-counsel defense. The decision whether to produce an opinion of counsel has been further complicated by inconsistent and often conflicting district court decisions that have made it impossible to accurately predict the scope of the resulting attorney-client and work-product waivers. Fortunately, In re EchoStar Communications Corp., 2006 U.S. App. LEXIS 11162 (Fed.Cir. May 1, 2006), clarifies the scope of the waivers and should allow defendants to make more informed decisions on whether to assert the advice-of-counsel defense to willful infringement....