By all accounts George and Ira Gershwin never considered making the family name part of the title of their most famous work, the 1935 opera “Porgy and Bess.”

But their heirs wield enormous power, and in the 1990s they re-branded it as “The Gershwins’ Porgy and Bess” as they sought business partners to adapt this four-hour opera into a perennial musical moneymaker the way shows like “Oklahoma!” have been under the careful management of the Rodgers & Hammerstein Organization. On Thursday, after years of fits and starts, “The Gershwins’ Porgy and Bess” will open on Broadway, updated and streamlined, part of a spate of unusually aggressive undertakings by musical-theater estates.

Few recent Broadway seasons have had as much estate-driven handiwork as this one, a reflection of the rising entrepreneurship of heirs and the affection of audiences for song standards. Heirs are increasingly hands-on in trying to wrest moneymaking shows out of their ancestral trunks: another current example is the producer Liza Lerner’s overhaul this winter of a musical by her father, Alan Jay Lerner, “On a Clear Day You Can See Forever,” for modern Broadway. (It drew mostly negative reviews.) The organization that represents the estates of Richard Rodgers and Oscar Hammerstein II recently authorized a stage version of the duo’s TV musical “Cinderella,” which is aiming for Broadway next season.

And the Gershwin estates have another musical coming to Broadway in March, “Nice Work if You Can Get It” starring Matthew Broderick, which is an attempt to take characters and songs from an old show (the Gershwins’ 1920s bootlegger musical, “Oh, Kay!”) and refashion them into a better musical that includes additional Gershwin tunes. The estates tried a similar reworking of “Oh, Kay!” in 2001 with the pastiche “They All Laughed,” but it hit a dead end after mixed reviews at the Goodspeed Opera House in Connecticut.