Fitbit has been targeted in a lawsuit over the capabilities of its sleep tracking features, in which it's accused of false advertising and common law fraud over the accuracy of its data.

Technology lawsuits are ten-a-penny in the States, and there's an entire industry devoted to suing companies for anything from dubious patents to claims over their products.

Essential reading: Fitbit Surge review

Now James P Brickman, who claims to represent a group of disgruntled Fitbit owners unhappy with the sleep tracking capabilities of its fitness trackers, has filed a lawsuit against the wearable company.

The lawsuit cites a 2012 study that found that Fitbit devices tend to overestimate sleep by an average of 67 minutes.

"Thinking you are sleeping up to 67 minutes more than you actually are can cause health consequences, especially over the long term," wrote the claimant, who has hired lawyers from Ohio and California for the case.

"[Fitbit] has made specific advertisement claims that for an extra charge, the customer can purchase a device which also contains a "sleep-tracking" function which will track "how long you sleep," "the number of times you woke up," and "the quality of your sleep," the claim states.

"In fact, the sleep-tracking function does not and cannot do these things. It does not perform as advertised. Consumers who purchase these products and pay the extra amount for this function do not receive the value of this function for which they paid," it continues.

Brickman is pursuing seven claims against Fitbit, ranging from false advertising and unfair competition to common law fraud, citing that Fitbit "wilfully, falsely, and knowingly misrepresented material facts relating to the character and quality of the sleep-tracking function, as stated above."

The suit targets the "Fitbit Force, Fitbit Flex, Fitbit One, Fitbit Zip, and Fitbit Ultra; as well as Fitbit's second-generation products, the Fitbit Charge, Fitbit Charge HR, and Fitbit Surge."

However, the Fitbit Zip is off the hook, as the claim states that it "does not have the 'sleep-tracking function' and the price for this base-model device does not reflect any extra charge for that function."

Naturally, Fitbit disputes the claims and got in touch with Wareable to confirm that it would be fighting the case.

"We do not believe this case has merit. Fitbit strongly disagrees with the statements about the product and the company contained in the Brickman complaint and plans to vigorously defend the lawsuit," a spokesman said.

"Fitbit trackers are not intended to be scientific or medical devices, but are designed to provide meaningful data to our users to help them reach their health and fitness goals," the company continued.

It's bad timing for Fitbit, which has just filed for a public offering, in which the company was initially valued at $100m.