Copyright, Interfaces, and a Possible Atlantic Divide Vezzoso Simonetta Recent copyright cases on both sides of the Atlantic focused on important interoperability issues. While the decision by the Court of Justice of the European Union in SAS Institute, Inc.v. World Programming Ltd. assessed data formats under the EU Software Directive, the ruling by the Northern District of California Court in Oracle America, Inc. v. Google Inc. dealt with application programming interfaces. The European decision is rightly celebrated as a further important step in the promotion of interoperability in the EU. This article argues that, despite appreciable signs of convergence across the Atlantic, the assessment of application programming interfaces under EU law could still turn out to be quite different, and arguably much less pro-interoperability, than under U.S. law. 340 periodical academic journal JIPITEC 3 2 2012 153 161 2190-3387 urn:nbn:de:0009-29-34449 vezzoso2012