Broadway theater owner the Nederlander Org has told stagehands union Local One that it will not participate in an implementation of new work rules threatened for Monday by the League of American Theaters and Producers.

Though not technically a defection by the Nederlanders, the decision nonetheless looks like a mark of disunity among producers amid the labor standoff between Local One and the league.

Landlord of nine Rialto theaters (including the ones housing megahits “Wicked” and “The Lion King”), Nederlander has a contract with Local One that is separate from the league’s. In the recent rounds of negotiation, it has observed but not participated.

“Although the league has reached an impasse with Local One, Nederlander is not at an impasse,” said League exec director Charlotte St. Martin in a statement. “As a result, the Nederlander Organization cannot legally implement these terms at this time. Regardless, they are fully supportive of the league’s effort and will remain so until a resolution is found.”

After both the league and the union laid down final offers that were not accepted last week, producers took a tough stance Tuesday, announcing that they would begin to implement some of the work rules from their last offer without the agreement of the union.

Decision was a potential provocation for Local One to call a strike, a process already set in motion with a strike vote skedded for Sunday. The league announced it would begin implementation Monday.

Producers and stagehands have been embroiled in tense labor negotiations for several weeks. At issue are contractual employment obligations that producers view as obsolete and overly costly, while the union refuses to give up those protections without equivalent gains elsewhere.

The darkening of several Broadway shows has long seemed a possibility, initially from a lockout called by producers. If the union membership authorizes a work stoppage on Sunday, then a strike initiated by the union could potentially shut down the Rialto.