Roswell artist Zheng Li was visiting an Atlanta gallery in 2012 when he was stunned to find a painting on display that struck him as a virtual copy of one of his own works—a colorful semiabstract depiction of a grand piano.

Li began investigating and quickly learned that the painting he saw was being peddled without his permission or knowledge via websites and in galleries and stores across the country, said John Bowler, a Troutman Sanders lawyer in Atlanta who represents the artist. That painting was signed “P. Roberts,” a name that Bowler said was a fiction.