Approximately 17,000 workers in AT&T’s traditional wired telephone business in California and Nevada walked out on strike on Wednesday, marking the most serious labor action against the carrier in years.
The walkout—formally known as a grievance strike—occurred after AT&T changed the work assignments of some of the technicians and call center employees in the group, the Communications Workers of America union said. The union would not say how long the strike might last.
A contract covering the group expired last year and there has been little progress in negotiations over sticking points like the outsourcing of call center jobs overseas, stagnant pay, and rising health care costs. The union said it planned to file an unfair labor charge with the National Labor Relations Board over the work assignment changes.
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Unlike competitor Verizon, which was hit with a bitter seven-week strike last year, AT&T has seen a lengthy period of constructive dealings with the CWA and other unions. Since the start of 2015, AT&T has completed 28 straight deals with its unions, covering 123,000 workers. The last strike at the company was in 2012, and just for two days.
AT&T officials say the company has offered annual wage and pension benefit increases and healthcare plans for landline workers in the latest negotiations—similar to what employees across the country have received in other contracts.
“A walkout is not in anybody’s best interest and it’s unfortunate that the union chose to do that,” an AT&T spokesman told Fortune. “We’re engaged in discussion with the union to get these employees back to work as soon as possible.”
The carrier’s success with its DirecTV and telecom workers stands in contrast to last year’s strike by some 40,000 Verizon telephone, Internet, and TV service workers as well as sparring between the CWA and T-Mobile over unionization of that carrier’s mobile phone workforce. Verizon workers got higher pay increases and better job security for call center workers in settling the strike, but made little progress on adding mobile workers to the union.
AT&T, by contrast, is the only one of the major carriers whose mobile workers are mostly unionized, and the company has been steadily extending union agreements across DirecTV.