Cartier has sued Tiffany & Co. for allegedly “stealing trade secrets” about its jewelry.

In the suit, which the Guardian reports was filed in New York on Monday, Cartier accuses Tiffany of stealing the trade secrets in question by way of a former employee. Tiffany, specifically, is alleged to have “hired away” junior manager Megan Marino as part of a larger effort to embolden their high jewelry-focused division.