Generally, in order to infringe a U.S. patent, the entire patented invention must be practiced within the United States. However, as technology evolves it is becoming harder to contain inventions within national borders. Specifically, the advancement of networking and communications technologies allows for the rapid, cost-efficient dissemination of information across countries’ borders. As a result, the number of inventions that are being practiced in multiple jurisdictions, or the practicing of divided infringement, is on the rise. Potential infringers that commit divided infringement are practicing patented inventions, escaping liability in all jurisdictions, but still reaping the rewards of the American market. Consequently, potential infringers who commit divided infringement are undercutting the incentive to innovate, the primary purpose of the patent system. To solve the problem of divided infringement, this Note proposes expanding the extraterritorial scope of U.S. patent law by adopting a substantial effects test, limited by comity concerns.