Abbott FreeStyle Libre Receives FDA Warning Letter

Understanding the FDA’s Warning Letter to Abbott, What It Means for FreeStyle Libre Users, and How Injured Patients Can File Lawsuits

On January 23, 2026, the U.S. Food and Drug Administration (FDA) issued a warning letter to Abbott Laboratories related to serious regulatory violations at its Alameda, California, facility that produces FreeStyle Libre continuous glucose monitors (CGMs). These devices, widely used by people with diabetes to track blood sugar levels continuously, have become essential tools in modern diabetes care. However, the recent letter raises significant concerns about the safety, accuracy, and manufacturing controls of some Libre models.

What Parker Waichman LLP Found

Parker Waichman LLP is monitoring the FDA warning letter and its implications for injured patients. Our key findings include:

• The FDA alleges systemic manufacturing and quality-control breakdowns at Abbott’s facility that could affect the accuracy of the Libre device.
• Patients who relied on defective devices may have made medical decisions based on incorrect glucose readings, potentially resulting in harm.
• The warning letter follows a serious recall tied to hundreds of adverse events and multiple deaths, underscoring possible risks.
• Abbott’s responses to the FDA were deemed inadequate, suggesting persistent compliance gaps.
• Individuals with injuries tied to FreeStyle Libre malfunctions may have legal claims for compensation.

According to the FDA, the methods and controls Abbott uses to manufacture, inspect, store, and release these devices do not conform to current good manufacturing practices. The agency described several defects that could affect device performance and patient safety. The warning letter was made public on February 3, 2026, and comes after an inspection of Abbott’s diabetes care site in October 2025. This action also follows a serious medical device correction Abbott issued earlier related to certain Libre sensors that led to hundreds of severe adverse events and multiple deaths.

For individuals who depend on CGMs to manage their diabetes, accuracy and reliability are not optional features; they are life‑critical. When a manufacturer fails to uphold quality systems and controls, it can result in device inaccuracies that lead to misinterpretation of blood glucose levels, improper dosing decisions, and dangerous health consequences.

We will now explain what the FDA’s warning letter alleges, how the production and testing of FreeStyle Libre devices may have fallen short of regulatory requirements, what that means for patients, and potential legal options for individuals harmed by malfunctioning CGMs.

What the FDA Alleges Against Abbott

The FDA’s warning letter identifies four major violations of quality system regulation requirements, which are intended to ensure that medical devices are manufactured to consistent and safe standards:

1. Inadequate Control Over Design Transfer

The FDA claims Abbott failed to establish procedures that reliably translate device design into manufacturing specifications. When a product design is finalized, a manufacturer must show that the design has been effectively transferred to the production floor—so that every device produced matches the validated design criteria.

According to the warning letter, Abbott did not clearly define whether critical accuracy performance testing is conducted by Abbott or its contract manufacturers. The FDA also indicated that Abbott’s response did not provide objective evidence that performance requirements were fully incorporated into manufacturing controls and final inspection criteria.

This is concerning because continuous glucose monitors must meet exact performance standards before being released to patients. Any gap in design translation can lead to inconsistent device quality and unreliable glucose readings.

2. Lack of Finished Device Acceptance Testing

The FDA also found that Abbott’s procedures for finished device acceptance were insufficient. The agency reported that Libre integrated CGM devices were being released without performance testing after final assembly, sterilization, packaging, and programming. Instead, Abbott tested unassembled components before these steps.

For an integrated device used to guide insulin dosing and other treatment decisions, final device performance testing is crucial. Without it, there is no assurance that the finished product works as intended once all parts are assembled and ready for patient use.

The FDA further noted that contract manufacturers responsible for final assembly were not provided with adequate performance testing specifications or required to verify accuracy prior to release.

3. Inadequate Statistical Acceptance Criteria

Another allegation concerns Abbott’s failure to use statistically valid techniques to determine whether devices meet performance standards. Sampling plans and acceptance criteria must be based on statistical justification so that only conforming devices are released.

The FDA said Abbott’s proposed sampling plans lacked objective justification, such as confidence levels, power analysis, or risk‑based rationale. These statistical tools are essential to ensure that testing catches defective units and that variability related to manufacturing is separated from biological variability seen in clinical contexts.

Without valid statistical methods, there is no reliable way to ensure only safe, accurate devices reach patients.

4. Failure to Validate Devices for Intended Use

The final major allegation is that Abbott failed to maintain a validated process to ensure that finished devices continue to function as designed under real‑world conditions. Even if a device met performance criteria during FDA premarket review, manufacturers are required to validate that performance in ongoing production.

The FDA determined that Abbott’s interim monitoring and future testing plans did not provide evidence that finished Libre devices would consistently meet accuracy requirements once released. Because these devices directly affect diabetes management, this is a serious concern.

The FDA’s warning letter states that Abbott must promptly address these violations and may face regulatory actions, including injunctions, civil money penalties, or product seizures if it fails to do so.

Why This Matters to FreeStyle Libre Users

For people with diabetes, a CGM is more than a convenience—it’s a tool that informs critical decisions about insulin dosing, diet, exercise, and overall health management. When device accuracy is in question, the risk of:

• Undetected high blood sugar (hyperglycemia)
• Unrecognized low blood sugar (hypoglycemia)
• Incorrect insulin dosing decisions
• Emergency medical interventions
• Hospitalizations or long‑term complications

increases significantly.

If a glucose monitor gives faulty readings, a user could mistakenly think their levels are within range when they are not. This can lead to dangerous insulin errors or a false sense of safety. Because Abbott’s FDA warning letter highlights deficiencies in manufacturing controls and a lack of final acceptance testing, patients and healthcare providers may reasonably question the reliability of specific FreeStyle Libre products.

Potential Legal Claims for Injured CGM Users

When a medical device causes harm due to defects in design, manufacturing, or quality control, injured patients may have grounds for product liability claims. Common legal theories include:

• Design Defect – Alleging the CGM was inherently unsafe or unreliable.
• Manufacturing Defect – Claiming a particular device did not meet safety standards.
• Failure to Warn – Arguing that patients were not properly informed about risks tied to device accuracy.
• Negligence – Asserting Abbott failed to uphold reasonable quality controls and safeguards.

Patients who suffered hypoglycemic events, hyperglycemic complications, hospitalizations, or other harms can potentially seek compensation for medical costs, pain and suffering, lost income, and long‑term care needs.

FDA vs. Abbott: A Comparison to Other CGM Manufacturers

Abbott is not alone in receiving regulatory scrutiny. Dexcom, a principal competitor in the CGM market, received a similar FDA warning letter in recent months related to its manufacturing practices. This reflects broader industry concerns about manufacturing quality, precision testing, and post‑market performance monitoring in diabetes care devices.

These warning letters signal that even top‑tier medical device manufacturers must maintain strict compliance with FDA quality system regulations to ensure patient safety.

FreeStyle Libre Injury Lawsuit FAQs

Can I file a lawsuit if my FreeStyle Libre device malfunctioned?
Yes. If a defective Libre CGM contributed to physical harm, hospitalization, or significant medical expense, you may have a product liability claim against the manufacturer, especially given the FDA’s recent findings.

Does a warning letter from the FDA prove liability?
A warning letter does not by itself establish legal liability, but it can be powerful evidence showing that a company failed to meet regulatory standards, which may support claims of negligence or defect.

What types of damages can injured patients seek?
In product liability cases, patients may pursue compensation for medical bills, therapy and monitoring costs, lost wages, pain and suffering, disability, and future treatment needs.

Do I need proof the device caused my injury?
Yes. Medical records, CGM data logs, physician statements, and documentation of adverse events are critical to linking device malfunction to your injury in a lawsuit.

How long do I have to file a claim?
Statutes of limitations vary by state. Speaking with a lawyer promptly helps ensure your claim is filed before legal deadlines expire.

Can family members file claims for a loved one who died?
In many states, survivors or estates may file wrongful death claims if a CGM malfunction contributed to a fatal outcome.

Contact Parker Waichman LLP For a Free Case Review

If you or a loved one experienced harm linked to a FreeStyle Libre continuous glucose monitor, including misreadings, hospitalizations, or complications from incorrect glucose data—legal options may be available. Parker Waichman LLP represents individuals injured by defective medical devices and can review your situation at no cost.

Call 1‑800‑YOUR‑LAWYER (1‑800‑968‑7529) for a free consultation to explore your rights, learn about potential claims, and understand your options for compensation. Regardless of your location or where your injury occurred, our nationwide product injury law firm is ready to assist you.