Altova GmbH and Massachusetts-based Altova, Inc., accused Romanian partnership Syncro Soft SRL of infringing U.S. Patent No. 9,501,456, titled “Automatic Fix for Extensible Markup Language Errors.” Altova asserts that Syncro Soft’s Oxygen XML Editor’s “Quick Fix” functionality infringes the patent. Altova alleges that venue in Massachusetts is proper because Syncro Soft is not a resident of the United States (and thus may be sued in any judicial district pursuant to TC Heartland) and that Syncro Soft is subject to jurisdiction because it conducts “substantial business” in the state, including at least part of its infringing activity.