Jack Sweeney, a Florida student, is now publicizing the movements of planes owned by Russian oligarchs, aircraft associated with President Putin

Mr. Sweeney's bot follows planes owned by Roman Abramovich, the oligarch owner of England's popular Chelsea Football Club, as well as aircraft owned by Leonid Mikhelson, head of Novatek, Russia's largest private natural-gas company, and businessman Alisher Usmanov, often cited as Russia's richest man. 

Mr. Usmanov is now on the European Union's sanctions list of 26 prominent Russians officials and businessmen, freezing their assets and imposing travel bans as it seeks to punish Russia's economy. Some oligarchs in recent days have distanced themselves from Mr. Putin.