While SMS marketing can be a great tool to drive growth and develop customer relationships, it also must be approached correctly. As evidence of the need to be aware of local and federal regulations, Wendy Davis of The Daily Online Examiner broke the news of a  Minnesota resident suing movie theater chain AMC for allegedly violating a federal texting law.

Andrea Addison claims that AMC sent her unsolicited coupons through a text message late last month. The message was supposedly sent to those in the theater's rewards program, called AMC Stubs. Addison admitted her enrollment into the program in 2012, but claims she let her membership lapse a year later. 

Addison and her attorneys are, claiming the message was incorrectly sent to other wireless telephone numbers. If true, AMC's actions would be in violation of the Telephone Consumer Protection Act, which prohibits the sending of text messages to consumers without their written consent via automated dialers. 

The lawsuit claims that enrollment in the rewards program did not constitute consent for SMS marketing purposes, including coupons for discounted concessions or money back for frequent film going. Addison also claims that allowing her membership in the program to expire should have severed all ties to that program, including advertising such as through text messages. 

"Consumers that provided their cell phone numbers were automatically included in defendants' SMS program which subsequently sent multiple text messages to those consumers," the lawsuit alleges.

Text message marketing is an effective tool, but one that has to be used carefully. Make sure to partner with a reputable provider and that systems are correctly recording opt-ins and opt-outs so that messages go to the right audience.