In what appears at first glance to be a simple, magnanimous act, a Russian billionaire is poised this week to return two Picassos, valued at $30 million, to the artist’s stepdaughter, who says the works, both portraits of her mother — Jacqueline Roque, Picasso’s second wife — were stolen from her.

The businessman, Dmitry E. Rybolovlev, owner of one of the world’s most valuable art collections, said in an interview last week that he bought the works in good faith in 2013, without any hint that there was a question about their title.