SAN FRANCISCO – As employee unrest simmered at Apple in late 2021, Tim Cook, the company’s CEO, sent an email reminding staff that the world’s most valuable company would do everything in its “power to identify those who leaked.”

The email spoke to the tech giant’s strictly enforced culture of secrecy that had kindled frustration among a group of former and current employees who collected accounts of verbal abuse, harassment and discrimination at Apple. Two of those former employees complained about the company’s policies to the National Labor Relations Board.

More than a year later, the labor board has found merit in the claim that Apple and its top executives have violated federal law with actions and policies that discourage employees from joining together to advance their interests.

A spokesperson for the labor board said Tuesday that it had determined that Apple’s work and confidentiality rules “interfere with, restrain or coerce employees” from collective action. If the parties are unable to settle the case, the board will issue a formal complaint against Apple and hold a hearing.

An Apple spokesperson didn’t immediately have a comment.

The labor board responded to five charges brought in late 2021 by two former Apple employees, Ashley Gjovik, an engineering program manager at Apple for six years, and Cher Scarlett, an engineer on the company’s security team. (After using a pseudonym to protect her anonymity, Scarlett said she legally changed her name in 2021.) Both women were involved in the early days of what would become the activist group #AppleToo, which began by collecting accounts of abuse, harassment and retaliation at the company.

Activists in the #AppleToo initiative shared a belief that the company’s strict culture of secrecy discouraged workers from airing concerns about problems at work with one another, family or the media. As a result, they said, problematic managers went unchecked and the company’s business conduct was seldom questioned.

In their claims to the labor board, the former employees accused Apple of trying to prevent the group from collecting wage data from employees, including through harassment. They also said the company’s work rules prevented them from discussing wages, hours and conditions of employment.

Scarlett also complained to the labor board about Cook’s email to staff. Shortly after an all-hands meeting, Cook sent an email to staff warning that the company did “not tolerate disclosures of confidential information, whether it’s product IP or the details of a confidential meeting.” He said people who leaked did “not belong” at Apple.

During the labor board’s review, a regional office “found merit to a charge alleging statements and conduct by Apple – including high-level executives – also violated the National Labor Relations Act,” a spokesperson for the board said.

Apple has continued to face challenges from workers since then, including over its corporate return-to-office policy and retail workers’ efforts to unionize.This article originally appeared in The New York Times.