The ex-wife of sanctioned Russian billionaire Arkady Rotenberg is seeking to trademark her ex-husband’s last name, according to information recently surfaced by Russian media.

Arkady Rotenberg was sanctioned by the U.S. and the European Union in 2014 for being a member of the Russian leadership’s inner circle and for making his fortune through his close ties to Russian President Vladimir Putin. Rotenberg is also Putin’s former judo partner.

Natalia Rotenberg, who kept her ex-husband’s last name after a three-year divorce process that concluded in 2016, filed a petition in December 2018 with the Russian Federal Service for Intellectual Property to trademark the last name “Rotenberg” in Cyrillic and Latin scripts. She has engaged in various business ventures in Russia and in the U.K. in the time since the divorce proceedings.