A federal class-action lawsuit filed in Illinois could have significant implications for the life safety and property protection industry because it challenges something installers, inspectors, authorities having jurisdiction and consumers have relied upon for decades: the meaning and reliability of a product’s UL listing.

On February 11, 2026, John Martucci filed a proposed class-action lawsuit in the U.S. District Court for the Northern District of Illinois against Underwriters Laboratories Inc., UL LLC, UL Solutions Inc., UL Standards and Engagement and UL Research Institutes. The case, Martucci v. Underwriters Laboratories Inc. et al., Case No. 1:26-cv-01561, is assigned to U.S. District Judge Martha M. Pacold.

The lawsuit concerns certain combination-listed burglar and fire alarm control units that use a single data bus. According to the complaint, UL tested alarm systems for compliance with applicable UL requirements and NFPA 72, but allegedly listed systems as compliant even though the plaintiff contends they had defects and did not satisfy applicable requirements. The complaint further alleges that information about those issues was concealed or not disclosed to consumers. These are allegations made by the plaintiff and have not been established as fact by the court. 

UL Solutions has publicly acknowledged the lawsuit in its filings with the U.S. Securities and Exchange Commission. Importantly, the company states that it believes the claims are **without merit and intends to vigorously defend the action**. As of its reported disclosure, UL Solutions said it could not reasonably estimate a possible loss or range of loss associated with the litigation.

Why the Allegations Matter to the Alarm Industry

The significance of this lawsuit extends beyond the particular equipment involved. Life safety and property protection professionals routinely depend on third-party listings when selecting, specifying, installing and approving equipment. A UL mark is not simply another logo on a control panel. Product listings are incorporated throughout codes, standards, specifications and regulatory requirements and are relied upon by manufacturers, installers, inspectors, fire officials, engineers and consumers.

That makes the central allegation particularly important. The lawsuit essentially asks what happens if a product carrying a recognized listing allegedly fails to meet the requirements that industry professionals reasonably believed the listing represented.

For an installing company, this raises difficult questions. Contractors generally do not have the laboratories, engineering resources or authority to duplicate certification testing every time they install a listed product. They purchase listed equipment precisely because an independent testing and certification process has already occurred. If litigation ultimately establishes that listed equipment failed applicable requirements, courts, regulators, insurers and attorneys may begin examining more closely what installers knew, what they reasonably should have known and what actions they took once information about a potential problem became available.

The specific architecture involved also deserves attention. The allegations concern combination burglar/fire alarm control units using a single data bus. A combination system may perform both property-protection and life-safety functions, but the consequences of a failure can be very different. A malfunction affecting burglary protection can result in property loss. A malfunction interfering with fire detection, notification or reporting can potentially involve loss of life.

The lawsuit references compliance with standards including NFPA 72 and UL requirements applicable to alarm control equipment. Industry commentary surrounding the litigation has also focused on UL 985, which addresses household fire warning system units, and UL 1023, which addresses household burglar alarm system units.

The Liability Question for Installers

Perhaps the most important lesson for alarm contractors is that a product listing should not be viewed as the end of a company's responsibility.

An installer should certainly be able to rely substantially upon recognized listings, manufacturer instructions and applicable codes when selecting equipment. But once an installer receives credible information indicating that a product may have a safety problem, continuing to install, service or leave that equipment in operation without investigating the issue can create a different liability question.

Documentation becomes extremely important. Companies should maintain records identifying the equipment installed at customer locations, including control-panel models, revisions when available, installation dates and service histories. If a manufacturer, testing laboratory, regulator or other authoritative source later publishes a recall, safety bulletin, firmware update or corrective action, good records make it possible to identify affected customers.

Service technicians also need a procedure for escalating unusual equipment behavior. Repeated communication failures, bus problems, intermittent device failures or unexplained troubles should not automatically be treated as isolated service calls when similar problems appear across multiple installations.

Equally important, companies should be cautious about removing, disabling or modifying listed equipment outside manufacturer instructions. An installer attempting to create its own solution to a suspected problem could unintentionally create another code, listing or liability issue.

Could the Case Change the Meaning of Certification?

That remains to be seen.

The case is still litigation, not a judicial determination that UL improperly certified alarm equipment. According to the publicly available docket, the court stayed discovery in April while the defendants prepared an anticipated motion addressing the complaint. ([Justia Dockets & Filings][1]) The industry's response therefore should not be panic or wholesale replacement of equipment merely because it is mentioned in allegations or online discussions.

The larger issue is what happens if the plaintiffs ultimately succeed.

A ruling establishing that a nationally recognized testing or certification organization could face liability for allegedly listing noncompliant life-safety equipment could affect far more than one family of alarm panels. Manufacturers may face additional scrutiny during certification. Testing laboratories could strengthen documentation and testing procedures. Insurers may ask more questions about listed equipment. Authorities having jurisdiction could become more cautious about combination systems or particular architectures. Dealers and integrators could face increased expectations to monitor safety notices after installation.

There could also be consequences for existing installed systems. If equipment is ultimately determined to have a material life-safety deficiency, manufacturers, certification organizations, regulators or courts could potentially require notifications, corrective actions, software changes, equipment modifications or replacement. Whether anything like that occurs in this case remains unknown.

What Alarm Companies Should Do Now

The appropriate response is awareness rather than assumption. Alarm companies should follow the litigation and information released by manufacturers, UL, NFPA and regulatory authorities. Companies should know which control panels they are currently installing and, where practical, maintain enough historical information to identify systems previously installed.

Technicians should follow manufacturer installation instructions and applicable editions of adopted codes and standards. Any documented manufacturer service bulletin, safety notice, recall or listing change affecting installed equipment should be evaluated promptly rather than placed in a file and forgotten.

Companies should also review their contracts, service documentation, inspection procedures and customer-notification policies with qualified legal counsel and their insurance professionals. The question is not simply whether equipment carried a listing on the day it was installed. Increasingly, liability disputes examine what a professional knew—or reasonably should have known—after installation.

Most importantly, installers should remember that this lawsuit has not established that the alarm systems at issue are defective or that UL acted improperly. Those remain allegations being contested in federal court. UL Solutions has expressly stated that it believes the claims lack merit and intends to defend itself vigorously. 

Nevertheless, Martucci v. Underwriters Laboratories deserves the attention of the entire life safety and property protection industry. The ultimate importance of the case may reach beyond a particular alarm panel or data bus. It could help define the responsibilities of testing laboratories, manufacturers and possibly the professionals who rely upon product certifications when designing, selling, installing and maintaining systems intended to protect lives and property.

Resources

* Federal Case Docket – Martucci v. Underwriters Laboratories Inc. et al.

* UL Solutions SEC Disclosure – Commitments and Contingencies

* UL Solutions March 31, 2026 Form 10-Q

* National Fire Protection Association – NFPA

* UL Solutions