(Reuters) - The manager of an Apple Inc ( AAPL ) retail store in Manhattan violated U.S. labor law by asking an employee whether he supported a union campaign, a federal labor board has ruled in its first decision involving the tech giant.

The National Labor Relations Board (NLRB) in a single-page ruling late on Monday said the manager's questioning of the worker, who had raised concerns about pay at a group meeting, amounted to unlawful interrogation and upheld a decision by an administrative judge.

The Democrat-controlled board also affirmed the judge's ruling that Apple ( AAPL ) illegally barred workers at the World Trade Center store from distributing union flyers.

Apple ( AAPL ), which has denied wrongdoing, did not immediately respond to a request for comment. The company can appeal the decision to a federal appeals court.

At least two Apple ( AAPL ) stores in the U.S. have unionized since 2022, and unions are working to organize several other locations including the World Trade Center store.

Workers and unions have filed more than two dozen complaints with the NLRB accusing Apple ( AAPL ) of a range of unlawful conduct. At least three of those cases are pending before administrative judges, including claims that Apple ( AAPL ) has refused to bargain at a unionized store in Oklahoma City.

Apple ( AAPL ) has denied wrongdoing in those cases. In Monday's case, the company had argued that the store manager had no intention to threaten the worker and her questioning of him was not the type of extensive interrogation the board had found unlawful in previous cases.

The board in a footnote in its decision said the manager's intent was irrelevant. The ruling requires Apple ( AAPL ) to post notices at the store informing workers that it violated the law and informing them of their legal rights.