Former staff at the video games firm behind Grand Theft Auto have joined a protest rally before the opening of an employment tribunal claiming they were sacked because they tried to unionise.

The 23 claimants who were dismissed last year for what Rockstar Games called "gross misconduct" have taken the gaming giant to court for unlawful dismissal.

The Independent Workers' Union of Great Britain (IWGB) claims the former staff were penalised for discussing working conditions in a private online forum while working on the upcoming Grand Theft Auto 6.

Rockstar Games, one of the UK's largest game developers, said it took action after staff discussed confidential information, including specific game features, on a Discord channel that was not private.

It said it was incorrect to link union activities to the dismissal of 31 UK workers, most based at the gaming giant's Edinburgh headquarters, and three in Canada in October 2025.

The claimants joined supporters in a rally outside Glasgow Tribunals Centre ahead of the first day of the hearing, which is expected to run until 16 October.

Dismissed staff previously told BBC Scotland News they were discussing working conditions at the firm in a private digital forum, not talking about projects.

IWGB called it a "ruthless act of union-busting".

Rockstar Games' upcoming Grand Theft Auto 6 is expected to break sales records when it is released on 19 November.

Pre-orders of the game are already thought to have been worth hundreds of millions.

Information about game development is tightly controlled across the gaming industry, with employees often signing legally-binding agreements not to share confidential information.

The employment tribunal against Rockstar began with legal discussion taking place. Evidence is expected to begin on Friday.

IWGB has alleged that the dismissals were unlawful both in the reasoning behind them and in the process used to carry them out.

The union claimed Rockstar targeted workers over union involvement, compiled and used lists of their names for the purpose of discriminating against them – known as "blacklisting" – and then denied them basic procedural protections by refusing to follow a disciplinary process or provide right of appeal.

In a statement, Rockstar Games told BBC Scotland News their position had been "clear and consistent throughout".

"Individuals across the UK and Canada were dismissed for gross misconduct following the sharing of confidential company information, not because of alleged trade union membership or activity," it stated.

"We reject the claims and will defend them vigorously before the tribunal."

Fans have been waiting 13 years for the next version of GTA after its 2013 predecessor became the second-best-selling video game of all time. The series is estimated to have sold half a billion copies since it launched in 1997.

Rockstar Games, which is renowned for its secrecy over its products, has faced enormous scrutiny from fans, investors, competitors and hackers ahead of the latest release.

The official announcement in November 2025 of a six-month delay to the game wiped $3.75bn off the share value of parent company Take-Two in 24 hours.