Venue in patent infringement cases is governed by 28 U.S.C. § 1400(b), which provides that a plaintiff may bring a patent infringement action either in (1) “the judicial district where the defendant resides”; or (2) “where the defendant has committed acts of infringement and has a regular and established place of business.” In TC Heartland, the Supreme Court made clear that a domestic corporation only “resides” in its state of incorporation. As a result, the focus of the venue analysis has now largely shifted to a question that was largely irrelevant before TC Heartland: what constitutes a “regular and established place of business” under the second prong of § 1400(b)? The answer to this question will play a large role in determining the practical impact of the TC Heartland decision. If courts hold that a “regular and established place of business” should be interpreted expansively – e.g., as including any judicial district in which a company has an authorized sales agent – plaintiffs will still have many of the venue options available before TC Heartland. If, however, courts hold that a regular and established place of business is more akin to a corporation's headquarters – venue options will be limited.