Hendricks said he was not only overcharged by AT&T, but that its alleged practice "curtailed his data usage to attempt to avoid incurring such fees, which prevented him from making full, or nearly full, use of the 200MB of data that he pays for every month."
Only AT&T customers who use one of the capped data plans would be eligible to join the lawsuit if it's granted class-action status.
Hendricks is not the only one who has complained of mysterious data plan charges.
"It was the next-to-last day of my billing cycle and I had used 150MB of the 200," said a user identified as MoodyMare11 in a Jan. 2 posting to Apple's support forum. "But when I woke up in the morning, I had a text stating that I had used 100 percent of my data and was now being charged for extra. I know apps can drain data, but 50MB literally overnight?
"Today I did not use data at all, I only used my phone when I was on Wifi and I checked the Wireless app out of curiosity," MoodyMare11 continued. "It said I had used 17MB of data today. What the heck?"
When asked for comment on Hendricks' lawsuit, an AT&T spokesman said, "We have only recently learned of the complaint, but I can tell you that we intend to defend ourselves vigorously. Transparent and accurate billing is a top priority for AT&T."
Hendricks' complaint spelled out five counts, including unjust enrichment, unfair business practices and violating the federal law that prohibits "unjust and unreasonable" telecommunication charges. It seeks restitution and class damages, which would be set by a jury.
Unlike several other lawsuits filed against AT&T by iPhone owners, Apple was not named in Hendricks' complaint.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer or subscribe to Gregg's RSS feed. His email address is email@example.com.
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