FILE - This Jan. 19, 2012 file photo shows a Broadway street sign in New York. The labor union representing theatrical performers is demanded that its members no longer participate in any developmental stage work with commercial producers, putting Broadway’s pipeline of new musicals and plays under threat. Actors’ Equity, which represents more than 51,000 actors and stage managers nationwide, declared the strike Monday after two years of fruitless negotiations with the producer-led Broadway League to increase minimum salaries for developmental labs and eventually share any profits with lab participants. (AP Photo/Charles Sykes, File)

NEW YORK | The labor union that represents theatrical performers is demanding that its members no longer take part in any developmental stage work with commercial producers, putting Broadway’s pipeline of new musicals and plays in jeopardy.

FILE – This Jan. 19, 2012 file photo shows a Broadway street sign in New York. The labor union representing theatrical performers is demanding that its members no longer participate in any developmental stage work with commercial producers, putting Broadway’s pipeline of new musicals and plays under threat. Actors’ Equity, which represents more than 51,000 actors and stage managers nationwide, declared the strike Monday after two years of fruitless negotiations with the producer-led Broadway League to increase minimum salaries for developmental labs and eventually share any profits with lab participants. (AP Photo/Charles Sykes, File)
FILE – This Jan. 19, 2012 file photo shows a Broadway street sign in New York. The labor union representing theatrical performers is demanding that its members no longer participate in any developmental stage work with commercial producers, putting Broadway’s pipeline of new musicals and plays under threat. Actors’ Equity, which represents more than 51,000 actors and stage managers nationwide, declared the strike Monday after two years of fruitless negotiations with the producer-led Broadway League to increase minimum salaries for developmental labs and eventually share any profits with lab participants. (AP Photo/Charles Sykes, File)

Actors’ Equity, which represents more than 51,000 actors and stage managers nationwide, declared the strike Monday after two years of futile negotiations with the producer-led Broadway League to increase minimum salaries for developmental labs and eventually share any profits with lab participants.

In labs, actors and writers workshop material for shows in progress. They’ve been used to create “The Cher Show,” ”To Kill a Mockingbird,” ”Hello, Dolly!” and “Waitress.”

The union has started making its case via social media, using the hashtag #NotALabRat. The strike comes as Broadway finished 2018 with the highest grosses on record.

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