If You Can't Beat 'Em, Join 'Em? How Sitting by Designation Affects Judicial Behavior *

IntroductionPatent claim construction-the act of figuring out in court what a patent covers-is the central inquiry in patent law.1 But it has also proven an enormous source of frustration for lawyers, courts, and policy makers over the past two decades. Most have lamented the high claim construction reversal rate and the uncertainty it creates.2 Scholars have offered various explanations and even suggested that the entire project of peripheral claiming is a failure.3 One of the particular sources of frustration for district judges is the fact that even substantial experience with patent cases doesn't seem to prevent their claim constructions from being reversed by the Federal Circuit.4In this Article, we find that one single act-a district judge spending a few days sitting by designation on the Federal Circuit as an appellate judge-is associated with a dramatic reduction in that judge's claim construction reversal rate. Our finding is robust to a variety of different controls. And while there are clearly selection effects at work in deciding who sits by designation on the Federal Circuit, our data suggest that individual judges themselves are treated differently after they sit by designation. We also demonstrate that this result is not a function of learning by the district judge but rather reflects a personal connection between the judge and the members of the reviewing court. Our results have interesting implications for the current regime of "informal deference" in claim construction,5 for Teva v. Sandoz6-a 2015 Supreme Court case that considered explicit deference to district judges in construing patent claims7-and for the practice of sitting by designation in the federal courts more generally. They suggest that the legal realists may have had it right all along-that judges are people, and their personal relationships can have more influence than legal doctrine on legal outcomes.In Part I we discuss the doctrine of claim construction and the scholarly literature on claim construction reversal rates. In Part II we present our study design and methodology. In Part III we present our findings. Finally, in Part IV we offer some thoughts about the implications of our results.I. Claim Construction and Its DiscontentsClaim construction is the central feature of most patent lawsuits.8 Courts construe claims before trial at "Markman9 hearings," and almost always do so before any consideration of dispositive pretrial motions such as summary judgment.10 And because claim construction must resolve any substantial dispute between the parties over the scope of the patent,11 it resolves the vast majority of the infringement disputes, paving the way for summary judgment12 or even stipulations that the defendant does or does not infringe.13 It can also have effects on seemingly unrelated doctrines.14Claim construction is a question of law decided by the judge, not the jury.15 As a result, the Federal Circuit held in Cybor16 that district court claim construction decisions are reviewed without deference in the appellate court.17 The Federal Circuit reaffirmed that conclusion en banc in Lighting Ballast18 over a vigorous dissent by four judges,19 but the Supreme Court recently revisited that question in Teva v. Sandoz.20Claim construction decisions have traditionally been reversed on appeal at very high rates. Kimberly Moore, David Schwartz, and others found claim construction error rates through the mid-2000s close to 40%, with most of those errors resulting in a reversal of the case as a whole.21 Unsurprisingly, the high reversal rate prompted great frustration among district judges.22 For example, shortly after Markman when the reversal rate neared 50% one judge noted that such a coin flip was the worst of all possible worlds-even a higher reversal rate would give more certainty.23 Scholars too have worried about the high reversal rate,24 and some have offered possible explanations.25 Most worrisome, Dave Schwartz finds no evidence that judicial experience with patent cases affects the reversal rate: district judges who have handled lots of claim constructions are no more likely to be affirmed than those with less experience. …