By Ken Fung (December 10, 2018, 11:28 AM EST) -- Since the U.S. Supreme Court's 2015 Teva Pharmaceuticals USA Inc. v. Sandoz Inc. decision changed the standard of review for extrinsic evidence in patent infringement cases, expert declarations and testimony during claim construction have become more heavily used and litigated.[1] Indeed, the Federal Circuit began applying the new standard in In re Papst Licensing Digital Camera Patent Litigation, which it issued two weeks after Teva.[2] One of the hotly contested issues that has emerged in the three-plus years since then is: What do you have to disclose during claim-construction discovery in order to rely on such expert evidence? The local patent rules in the patent-heavy Eastern District of Texas and Northern District of California don't squarely address this issue. But thanks to the corpus of decisions post-Teva, a clearer picture of expert disclosure requirements has emerged....