ALBANY – Landlords cannot deregulate rents on units under luxury decontrol provisions of the Rent Stabilization Law while accepting public tax incentive benefits, the Court of Appeals decided yesterday.

In a ruling that the dissenters warned would have a significant fallout in the courts and troubled real estate industry, a 4-2 majority held that thousands of units in Manhattan’s sprawling Peter Cooper Village and Stuyvesant Town complex were illegally decontrolled by Tishman Speyer Properties and its previous owner.