Broadway performers and stage managers are demanding a share of the profits from hit shows they help to create, setting off a labor dispute that is threatening to disrupt the high-stakes development of new musicals and plays.

Actors’ Equity, a national labor union, and the Broadway League, a trade association representing producers, are at odds over the issue two years after public pressure from the original cast of “Hamilton” prompted that blockbuster show’s producers to agree to a new formula for distributing its proceeds.

Equity says the two sides are at an impasse and it is considering a limited strike in which it would bar its members from participating in any developmental work with commercial producers. The union says it is unhappy with how its members are compensated for work in developmental labs, which are generally four-week sessions in which actors and writers test out material for shows in progress. Recent productions that have used labs include “The Cher Show,” “To Kill a Mockingbird,” “Hello, Dolly!” and “Waitress.”

“After two years of wrangling and negotiating we are just at a standstill,” Mary McColl, the union’s executive director, said.