SAN FRANCICO (CBS 5) – Business seems to booming for text message spammers, despite the fact that the practice violates California law.

Kent German with CNET said, in the last few years, spam by phone has skyrocketed.

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“Spammers are learning,” German said. “It’s a new avenue for people to communicate, sell things, and get out advertisements.”

German added that spammers are able to obtain phone numbers through several different sources.

“Anytime you enter you phone number and you buy something, enter a political donation, those sources could sell your phone number,” he said.

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“The law in California says you’re not allowed to be bombarded with spam text messages and that’s because most people end up paying for them,” said consumer advocate Harvey Rosenfield.

If consumers are charged, Rosenfield said charges could be recovered in small claims court. But there are some exceptions to the law. For instance, the law does not apply if consumers give consent or if there’s an option to opt out.

Still experts suggest never replying to unfamiliar numbers and adding your phone number to the do not call registry. AT&T, Verizon and Sprint offer free online options that allow consumers to block specific numbers. T-Mobile charges a 4.99 charge to block phone numbers.

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