Some 20,000 workers in AT&T’s traditional wired phone and Internet businesses walked out on Friday night, a few weeks after their contract expired. Their union, the Communications Workers of America, said the strike was to protest AT&T sending negotiators to talks without the power to make decisions about a new contract.

Neither side was saying much on Wednesday after the strike ended. The union declared victory, saying it had “showed the power that working people have when they join together.” AT&T declined to comment beyond confirming that workers were back at work.

Several other groups of AT&T unionized workers conducted short strikes back in 2017, but generally the telecommunications giant has good labor relations. The company has not suffered a serious strike, like the 49-day Verizon worker action in 2016, in many years. It’s been over 30 years since 155,000 AT&T workers walked out for a month and AT&T says recently it has concluded successfully 20 contract agreements covering 89,000 employees since 2017.

At midday on Wednesday, shares of AT&T were unchanged. The stock is up 28% so far in 2019, outpacing the 15% gain in the S&P 500 Index.

Despite the strong stock performance at AT&T and its rivals, and looming over the industry’s talks with its unions, the traditional telecommunications business remains under pressure, with the number of landline phone lines shrinking every year. And the cable industry is gaining market share from the telecom carriers in the still-growing broadband Internet market, adding to the pressure.

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