The National Labor Relations Board will file a complaint accusing Alphabet Inc's Google of unlawfully monitoring and questioning workers, who were fired for protesting against company policies and trying to organise a union, the former employees said in a statement on Wednesday.
The NLRB did not respond to a request for comment.
Google said it was confident in its legal position.
"Google has always worked to support a culture of internal discussion, and we place immense trust in our employees," it said. "Actions undertaken by the employees at issue were a serious violation of our policies and an unacceptable breach of a trusted responsibility."
The complaint follows a year-long investigation prompted by a petition by five people fired by Google after they led efforts to protest company policies and organise colleagues into a potential union. The Communications Workers of America union helped author the workers' charge.
Google said the workers breached information security rules.
Their firings capped two years of battling between Google and its workforce, particularly in the United States. At issue is how much input the rank and file has on which projects the company takes on and how it handles sexual misconduct and other workplace matters.
One of the fired workers, Laurence Berland, described the NLRB's move as significant "at a time when we're seeing the power of a handful of tech billionaires consolidate control over our lives and our society."
Berland said the NLRB found Google violated labour law by placing workers on administrative leave and terminating one of them for accessing documents related to how the company polices internal forums. The agency also found unlawful Google's policies for limiting access to some documents and its practices for investigating workplace organising, according to Berland.
The NLRB did not include in its complaint several other allegations sought by the workers, who said they would appeal.
The NLRB's case is expected to be heard and decided by an administrative law judge in the coming months.
Deccan Herald is on WhatsApp Channels| Join now for Breaking News & Editor's Picks