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Oscar statues are seen at the Kodak Theatre, which is the site for the 84th annual Academy Awards.

If you're gearing up for the Oscars and looking to make some safe bets on probable winners in the acting categories there is a rule of thumb you might want to follow. No, it's not the Golden Globes or the SAG awards. In recent decades the path to Oscar gold for many actors has increasingly led through biopics.

Film critic Mick LaSalle noticed this trend and he wrote about it in the San Francisco Chronicle.