Non-US corporations, especially banks, have long experienced the expansive enforcement of unilateral US sanctions regulations. The common factor in these cases is that jurisdiction is based on the alleged use of the US financial system. A recent case shows that the US authorities have expanded their jurisdictional claim even further by establishing a new theory of sanctions liability. Under what we call the correlation theory, a sufficient US nexus exists if a sanctions-related transaction correlates with a transaction which, at some point, is processed via the United States. This expansion signifies an enlargement of what the United States considers as primary sanctions. It goes hand in hand with a reduction of what it considers to be secondary sanctions. So far, the US authorities have not provided a clear and comprehensive definition of their newly developed liability framework. Less nebulous than the parameters of the correlation theory is the outcome it produces: any transaction involving a sanctioned client by an internationally active bank can potentially be pulled into US sanctions jurisdiction.