Instagram's attempt to change its terms of service has inspired not only a user backlash but also-- now -- a class-action lawsuit.

The proposed terms of service were introduced last week, though Instagram has since backpedaled. The lawsuit -- filed in U.S. District Court in San Francisco on Friday and first reported by Reuters -- argues that the proposed changes would "transfer valuable property rights to Instagram while simultaneously relieving Instagram from any liability for commercially exploiting customers' photographs and artistic content, while shielding Instagram from legal liability."

Instagram is making a "grab for customer property rights," the suit claims, and is attempting to cover its tail by prohibiting users from seeking legal injunction against the service, or indeed -- through a no-class-action arbitration clause -- any legal action aside from small-claims remedies. The proposed terms would also "artificially limit the statute of limitations for all claims against Instagram to 1 year," the suit says.

The suit says the plaintiff -- Lucy Funes of San Diego -- "is acting to preserve valuable and important property, statutory, and legal rights" before legal action is "forever barred by adoption of Instagram's New Terms."

Instagram had said that the new terms of service would go into effect January 16 and that users could not opt out but could delete their accounts before the deadline. The lawsuit takes issue with that last point, saying customers could cancel, but that in doing so would forfeit the right to their photos. "In short," the suit says, "Instagram declares that 'possession is nine-tenths of the law and if you don't like it, you can't stop us.'"

Instagram parent Facebook told Reuters the "complaint is without merit and we will fight it vigorously."

Here's the filing, which was posted by AllThingsD's Mike Isaac: