When you sign up for one kind of message service, you might not expect, or want, messages about that service elsewhere. As such, Yahoo is facing a class-action lawsuit that claims the company’s Messenger service spammed some Sprint cellphone customers with unwanted texts, which could put it on the line for costly fines if it loses in court.

U.S. District Judge Manish Shah ordered that a lawsuit originally filed by an Illinois resident in 2014 now applies to all Sprint cellular customers in the U.S. who received a certain kind of text message from Yahoo in March 2013, reports the Wall Street Journal. That could mean more than 500,000 members, the judge wrote.

The complaint claims Yahoo violated the Telephone Consumer Protection Act of 1991 by sending unsolicited text messages — or spam texts — from Yahoo Messenger. It essentially took instant messages and translated them into texts that could be sent to a cellphone, including a “welcome message” that urges the user to respond.

The lawsuit wants Yahoo to pay at least $500 for every violation of the rule, which bars unsolicited automated texts, phone calls or fax messages, and allows the recipient to sue for damages of $500 to $1,500 per violation.

Yahoo isn’t commenting on pending litigation, but says that the texts aren’t spam at all, they’re a good thing — because they’re “not the type of annoying, intrusive mass communication” barred by the Telephone Consumer Protection Act. Instead, they simply alert recipients that they’ve gotten a message from another user, say what that message is and gives them actions to take, one of which is blocking future messages.

Yahoo Faces Class-Action Suit Over Spam Texts [Wall Street Journal]

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