HOLLYWOOD (CBSLA.com) — The SAG-AFTRA actor’s union went on strike Friday against 11 video game companies following 19 months of negotiations centering on greater compensation for voice-over and stunt performers.

The strike began at 12:01 a.m. and covers games that went into production after Feb. 17, 2015, according to a union statement.

The union says its members would picket one of the targeted companies – Electronic Arts in Playa Vista – starting at 10:30 a.m. Workers from Activision Publishing, Disney Character Voices, Insomniac Games, VoiceWorks Productions, Blindlight, Interactive Associates, WB Games, Corps of Discovery Films, Formosa Interactive and Take 2 Interactive Software are also on strike.

The union, the largest in the entertainment industry, is reported to be seeking a compensation structure that would allow actors to start receiving residual-like payments based on a game’s commercial success. It also demands improved safety conditions for performers.

The proposed bonus system would allow actors to receive additional payments for every 2 million copies or downloads sold, with a cap at 8 million, according to the Los Angeles Times. Video game companies instead proposed a 9 percent wage increase, plus additional compensation of up to $950 per game based upon the number of sessions a performer works on a particular video.

The parties have largely reached agreement on other outstanding issues, including vocal stress and stunt coordination, and have made substantial progress on transparency, according to an attorney on the companies’ negotiating team.

A federal mediator joined the discussions Wednesday but did not stave off the strike, whose intended duration was not immediately reported.

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