A tremendous amount of litigious time and energy is spent fighting over opinions of counsel and associated waivers. Formal non-infringement or invalidity opinions are usually designed for litigation -- their sole purpose to reduce that a defendant will be held liable for treble damages. The formal opinions are -- as you might expect -- stiff and formal. The good ones are exceedingly thorough and cover all the legal bases. Yet, formal opinions often fall far short of honestly answering the important question: "What are my chances of winning if I'm sued on this patent?" That question is much more nuanced.
Opinions of counsel are protected as attorney work product and usually attorney-client privilege as well. When the opinion is presented to court, those protections are waived. Many courts extend the scope of the waiver to include any related opinions (whether formal or informal) provided to the client. This waiver has, on occasion, been extended to litigation counsel even when an outside firm provided the formal opinion.
The logic behind the broad waiver may help avoid nefarious behavior: A potential defendant would like to obtain several separate opinions, then only produce the 'best' one. Such a scenario would hardly comport with the 'reasonable reliance' standard. In addition, a broad wavier helps the patentee's counsel ensure that any opinion is based on a solid background rather than potentially faulty information. (sword vs. shield)
One reason why waiver issues are fought so fiercely is that court outcomes are all-over-the-map. Some courts grant broad waivers while others are quite narrow.
In Seagate, the lower court granted a broad waiver to include otherwise privileged communication between the defendant and its trial counsel "even if it is communicated in the context of trial preparation." The waiver was also extended to include in-house counsel's internal discussions with business executives. The Court of Appeals for the Federal Circuit, acting sua sponte, has requested an en banc hearing to determine the scope of opinion waivers.
In its opening brief, Seagate takes the position that "opinion and trial counsel have entirely different roles," and those roles require that the waiver be limited to opinion counsel. Seagate also focuses on the result -- that litigation attorneys will stop talking with their clients, resulting in worse legal representation. Clear rules will also "foster predictability."
I agree that this case is very important for patent litigants, but the interesting aspect involves the interplay between general practice and boutique firms. (More to come on this).