Pic, which is set to lense in Paris on September 26, has sold to U.K. (Curzon Film World), Australia and New Zealand (Hopscotch/eOne), Germany and Switzerland (Ascot Elite), Scandinavia (Svensk), Benelux (Imagine), South Africa (Nu Metro), Israel (Lev Films), Greece and Cyprus (Feelgood), Middle East (Front Row), Portugal (Lusomundo) and Airlines (EIM).
BBC Films is also backing the project.
Smith and Kline star alongside Kristin Scott Thomas and Dominique Pinon.
"My Old Lady" tells the story of a down-and-out New Yorker who travels to Paris to liquidate a valuable apartment he has inherited from his estranged father. Once there, he discovers a refined old woman, who turns out to be his father's lover, living in the apartment with her daughter.
Film is written and helmed by playwright and screenwriter Horovitz and is based on his award-winning play.
Horovitz's screenwriting credits include Isvan Szabo's "Sunshine," "Author! Author!" and "The Strawberry Statement."
"Moneyball" producer Rachael Horovitz produces with Gary Foster ("Sleepless in Seattle") alongside Nitsa Benchetrit and David Barrot.
David Atrakchi, Boris Mendza and Gael Cabouat for Fulldawa Films co-produce.
Charles Cohen and Daniel Battsek will exec produce for CMG while BBC Films' Joe Oppenheimer and Christine Langan will exec produce for BBC Films.
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