Quest Diagnostics Data Breach Investigation October 22, 2026 Update · Quanum Lab Services Manager Canonical URL: https://hallattorneys.com/investigations/quest-diagnostics Last reviewed: October 22, 2026 Hall Attorneys is investigating the Quest Diagnostics data security incident involving Quanum Lab Services Manager (LSM). Quest has confirmed unauthorized access involving patient information. The specific data and number of people affected remain under investigation. Did you receive a Quest security notice or learn that your patient information may have been involved? Contact Hall Attorneys to discuss your concerns and request a case review. What did Quest disclose? In its update dated noon ET on October 22, 2026, Quest reported unauthorized access to Quanum Lab Services Manager, a system some healthcare clients use for test ordering and results. Quest suspended access while investigating. October 22 is the date of the reviewed update, not a confirmed date when unauthorized access began. Quest says its core business operations continue and that direct laboratory interfaces and electronic medical record connections were unaffected. Its notice identifies paper requisitions and Quanum eLabs as alternatives for LSM clients. Providers should check the official notice for current service instructions. Sources: Quest Diagnostics: Update on the Quanum LSM incident (October 22, 2026): https://www.questdiagnostics.com/links/quanum-notice What patient information was involved? Quest says it believes some patient data in Quanum LSM was accessed. Its FAQ confirms that patient health information (PHI) or patient identifiable information (PII) was part of the unauthorized access, while the specific data affected remains under investigation. The reviewed notice does not identify the particular data fields involved or disclose an affected-person count. It does not establish that Social Security numbers, financial information, or any particular test result was accessed. Having a Quest test or a Quest account does not, by itself, establish that your information was involved. The scope of this investigation concerns the Quanum LSM incident and its effects on individuals whose records may have been accessed. Sources: Quest Diagnostics: Update on the Quanum LSM incident (October 22, 2026): https://www.questdiagnostics.com/links/quanum-notice Who should contact Hall Attorneys? We would like to hear from patients and others who have information about this incident, particularly anyone who: - Received a notice from Quest or a healthcare provider about the Quanum LSM incident. - Was told that their patient information may have been accessed. - Received suspicious communications using private testing or healthcare details. - Spent time or money responding to a possible disclosure or experienced other related harm. You do not need a breach notice to request a review. Tell us what happened and when; suspicious activity alone does not establish a connection to this incident. Will affected people receive a notice? Quest says it is identifying impacted patients and providers and will make notifications required by applicable law. The reviewed update does not establish that individual notices have already been sent. Check Quest’s official notice for updates. Keep any letter, email, or provider communication you receive, including the date and any instructions or deadlines. Sources: Quest Diagnostics: Update on the Quanum LSM incident (October 22, 2026): https://www.questdiagnostics.com/links/quanum-notice What are we investigating? Hall Attorneys is reviewing how patient information was protected, the circumstances of the unauthorized access, the scope of affected records, the response and notification process, and any resulting harm. We are evaluating potential legal claims, including whether a class action is warranted. This page describes an investigation. Hall Attorneys has not filed a lawsuit concerning this incident, and no recovery is promised. What records should you keep? Preserve security notices, envelopes, emails, provider correspondence, suspicious messages, and account alerts. Keep records of expenses, time spent responding, and any suspected misuse. You can describe records you already have before sending documents. Do not search for, download, or share allegedly stolen patient information. Keep only records you are authorized to access. Request a case review For an initial inquiry, provide your name, state of residence, a safe way to reach you, and whether you received a Quest or provider notice about Quanum LSM. Briefly describe your concern and any related costs. Let us know whether it is safe to leave a voicemail. Do not include medical records, diagnoses, test results, Social Security numbers, passwords, or complete financial-account information in an initial email or website submission. If sensitive records are needed, we will discuss an appropriate way to provide them. Nicholas Hall Email: nhall@hallattorneys.com Phone: 713-428-8967 Request a Case Review: https://hallattorneys.com/connect Attorney Advertising. Responsible attorney: Nicholas Hall, Hall Attorneys, P.C., Edna, Texas. Hall Attorneys is not affiliated with Quest Diagnostics. This page describes an investigation, not a filed lawsuit by Hall Attorneys. It provides general information, not legal advice. Contacting the firm or submitting information does not create an attorney-client relationship. No outcome is guaranteed.