Defective Products

Fitbit Heart Rate Monitors Fraud & Defects Lawsuit

Allegation: Fraud and misrepresentation

June 2018 Case Update

On June 5, 2018, Judge James Donato of the U.S. District Court for the Northern District of California issued an order denying Fitbit’s motion to dismiss the class action lawsuit alleging that its PurePulse-equipped devices are grossly inaccurate and frequently fail to record any heart rate at all. The lawsuit brings claims for false advertising, unfair competition, common-law fraud, fraud in the inducement, unjust enrichment, breach of express warranty, breach of implied warranties under the Magnuson-Moss Warranty Act, and under the Arizona Consumer Fraud Act. While the court removed plaintiff’s unjust enrichment claim, the motion to dismiss was otherwise entirely denied, subject to plaintiff’s agreement to amend the complaint to include product packaging statements and further allegations of reliance.

In its Order, the Court noted, “According to the complaint, the ability to record heart rate in real time and during physical activity is marketed as a key feature of the PurePulse devices, yet in reality the products frequently fail to record any heart rate at all or provide highly inaccurate readings, with discrepancies of up to 75 bpm. Those facts indicate that the devices lack even a basic degree of fitness for use as exercise or activity monitors.”

Lieff Cabraser partner and attorney for plaintiff Jonathan D. Selbin notes, “We are pleased that the Court recognized the strength of our claim that Fitbit misled consumers when it marketed its Fitbit trackers as being able to continuously and accurately measure heart rate during exercise. As independent test after test has shown, these devices are wildly inaccurate and cannot be relied upon to monitor heart rate during exercise reliably and safely.”

The case will move forward on all claims apart from that for unjust enrichment.

Earlier Case Updates

On May 31, 2018, U.S. District Judge James Donato indicated that Fitbit may face civil contempt charges for what he termed “gamesmanship” after the company leveraged an arbitration agreement to shrink the class action lawsuit over alleged deficiencies in its heart rate monitors then quit the arbitration when the plaintiff didn’t like its settlement offer (read the hearing transcript).

Judge Donato had directed Fitbit and the arbitrator to determine whether 12 plaintiffs’ claims about the Fitbit devices, which consistently mis-record heart rates, particularly during the vigorous exercise for which many consumers purchase the devices, should be heard in open court or only in closed arbitration.

After Fitbit asked the arbitrator to drop the matter, calling the plaintiff irrational, Judge Donato returned a sharp reply, noting that Fitbit could not unilaterally moot a claim and that he was “taken aback” that the company persisted in focusing on the value of the Fitbit device.

“I am developing a very slow burn from an unacceptable level of gamesmanship by Fitbit,” the Judge said. “For Fitbit to now say, ‘This is not arbitrable because it’s too cheap and she’s crazy as a result of that,’ strikes me as profoundly troubling, to the point where I’m beginning to wonder if this is a form of civil contempt. … I will tell you that if I find Fitbit has forced this case out of court only to play games at arbitration, there will be an accounting.”

Background on the Fitbit Heart Rate Monitors Fraud Lawsuit

On January 5, 2016, Lieff Cabraser and co-counsel filed a fraud class action lawsuit on behalf of consumers nationwide against Fitbit, Inc. over complaints that heart rate monitors sold by Fitbit — the Fitbit Blaze, Charge HR and the Fitbit Surge — fail to accurately measure user heart rates. Complete the form below to learn more about your legal rights and help us hold Fitbit accountable.

On May 19, 2016, plaintiffs filed an amended complaint citing, among other things, a comprehensive new study conducted by researchers at California State Polytechnic University, Pomona revealed that the PurePulse™ heart rate monitors in the Fitbit Surge™ and Charge HR™ bear an “extremely weak correlation” with actual users’ heart rates as measured by a true electrocardiogram (ECG) and are “highly inaccurate during elevated physical activity.”

In March of 2018, a team of researchers from the University of Leeds (UK) and TSW xp LAB in Italy published a new peer-reviewed study on the Fitbit Charge 2 fitness tracker confirming findings from previous studies that the “PurePulse™” technology used in Fitbit’s popular fitness trackers can be extremely inaccurate during moderate and high-intensity exercise. This most recent study found inaccuracies in the devices of up to 30 beats per minute. Previous testing at the University of Wisconsin showed Fitbit tracker inaccuracies of between 20-40 beats, or 12.5-25%. In tests conducted at the Cleveland Clinic Heart and Vascular Institute, the Fitbit HR experienced a 16% error rate for heart rate during moderate treadmill exercise and “fell short” of the mark for consumers.

Fitbit Blaze, Charge HR, and Surge Heart Rate Monitors

Fitbit advertises its heart monitors as the most accurate wrist-worn wireless tracking devices on the market. Fitbit claims to have conducted “multiple internal studies to rigorously test” the accuracy of the wrist-mounted monitors.

The Fitbit Charge HR is an enhanced version of the Fitbit Charge activity tracker wristband that adds continuous heart-rate monitoring. Fitbit claims the Charge HR allows users to “maintain workout intensity, maximize training, and optimize health.”

The Fitbit Surge retails for about $100 more than the Charge HR. It is part smartwatch, part GPS running watch and includes all-day heart-rate tracking. Fitbit promotes the Surge as the “ultimate fitness superwatch” that allows athletes to maximize their training by keeping them “in the zone” and without “guessing” one’s heart rate.

Importance of Accuracy in Fitness Heart Rate Monitors

Heart rate monitors are used by athletes and others who need to reach or not exceed target heart rates. The use of monitors reporting inaccurate heart rates can lead to serious consequences.

As explained in a review of these devices by, “Heart rate training relies on exercising in different heart rate zones – each of which is a percentage of your maximum heart rate and stimulates different metabolic pathways and has different effects on the enzymes in the muscles. Once you know your zones, you can schedule workouts to make the greatest fitness gains without overworking your body, that is, if you are measuring the zones correctly.”

Consumer Complaints That Fitbit Heart Rate Monitors Are Defective Devices

As noted above, on January 5, 2016 consumers from California, Colorado, and Wisconsin filed a nationwide class action lawsuit against Fitbit, Inc. alleging that Fitbit’s wrist-based “Charge HR” and “Surge” heart rate monitors do not and cannot consistently record accurate heart rates during the intense physical activity for which Fitbit expressly markets the devices in widespread advertising. The suit contends — and expert testing confirms — that the Heart Rate Monitors consistently mis-record heart rates by a significant margin, particularly during intense exercise. Not only are accurate heart readings important for those engaging in fitness, they can be critical to the health and well-being of people whose medical conditions require them to maintain (or not exceed) a certain heart rate.

Prior to the suit’s filing, consumers complained on online review sites and other forums that the Fitbit heart rate monitors were flawed because they provided unreliable heart rates readings when user were exercising.

These complaints were made by athletes who simultaneously tested their heart rates using the Fitbit devices and other types of heart rate monitors. In numerous instances, the consumers stated that their FitBit device gave heart rate readings during their exercise routines that were 20-50% less than the heart rates measured by these other devices.

Submit Your Fitbit Complaint

If you purchased the Fitbit Charge HR or Fitbit Surge for monitoring your heart rate, we welcome the opportunity to learn of your experience with the device. We will review your claim for free, confidentially, and with no obligation on your part.

We will respond to your inquiry as promptly as possible. There is no charge or obligation for our review of your case. Please note that completion of this form cannot contractually obligate plaintiffs’ attorneys to represent you. We can only serve as your attorney if you and we both agree, in writing, that we will serve as your counsel.

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About Consumer Law

State and federal laws provide consumers with remedies for products that are defectively designed or manufactured, or which do not perform as advertised. In many cases, consumers can benefit from such laws even after a warranty period has expired.

The cost for a consumer to hire an attorney and file an individual lawsuit against the manufacturer of a defective product is often prohibitive. The law, however, does not leave the consumer powerless.

A small number of consumers may file a class action lawsuit, representing all consumers who purchased the defective product. A class action suit can provide a powerful and effective means for consumers to compel a corporation to acknowledge its legal responsibilities and provide just compensation to the class members.

About Lieff Cabraser

Recognized as “one of the nation’s premier plaintiffs’ firms” by The American Lawyer, Lieff Cabraser has successfully litigated and settled hundreds of class action lawsuits, including dozens of cases requiring manufacturers to refund the cost of worthless and defective products or costs the consumer incurred in repairing them, to fix the defects, and to extend consumer warranties.

Trademark Notice

Fitbit, Fitbit Charge HR, and Fitbit Surge are registered trademarks of Fibit, Inc. The use of these trademarks is solely for company and product identification and informational purposes. Fitbit, Inc. is not in any affiliated with Lieff Cabraser Heiman & Bernstein, LLP. Nothing on this website has been authorized or approved by Fitbit, Inc.