FDA Cites Linemaster Switch Corporation in 2026-05-27 Warning Letter — CGMP/QSR/Drug/Medical Devices/Adulterated
Letter issued · posted to fda.gov .
Subject as published: CGMP/QSR/Drug/Medical Devices/Adulterated
TL;DR
The FDA's Center for Devices and Radiological Health issued a warning letter (CMS #730215, May 27, 2026) to Linemaster Switch Corporation, Woodstock, CT, finding that its foot pedal accessories for Class II and Class IV medical lasers are adulterated under 21 U.S.C. § 351(h) due to non-conformity with Current Good Manufacturing Practice requirements in 21 CFR Part 820. The violations include: failure to document rework procedures (undocumented rework of nonconforming units risked unintended laser activation); failure to implement required risk management and Process FMEA documentation for foot pedal products used with Class IV lasers; and failure to implement corrective action procedures, including an uninvestigated 2023 corrective action request involving six foot pedals that failed calibration verification at a customer facility. The FDA requested revised procedures, retrospective review summaries, and timelines for completion.
Argus analysis
# FDA Warning Letter Analysis: Linemaster Switch Corporation
**Company and Findings**
Linemaster Switch Corporation, based in Woodstock, Connecticut, manufactures foot pedal accessories for medical devices, including Class II controls used with Class IV medical lasers. An FDA inspection conducted from February 4 through March 6, 2026, by the Center for Devices and Radiological Health identified that these devices are adulterated under section 501(h) of the Federal Food, Drug, and Cosmetic Act because manufacturing did not comply with current good manufacturing practice requirements.
**Regulatory Citations**
The warning letter cites five violations of 21 CFR Part 820, the Quality Management System Regulation, and references ISO 13485:2016 standards. Primary deficiencies include: inadequate rework documentation (Clause 8.3.4); missing process failure mode and effects analysis for foot pedal controls (Clause 7.1); non-implementation of corrective action procedures for customer complaints, specifically an open SCAR from 2023 with blank root cause analysis (Clause 8.5.2); absent environmental monitoring procedures despite a documented temperature-drift issue identified in 2013 (Clause 6.4.1); and insufficient software validation for calibration equipment, with multiple units passing internal testing but failing customer verification (Clause 7.6). These citations typically indicate systemic gaps in design controls and post-market feedback integration.
**Response Timeline and Industry Monitoring**
Linemaster submitted a response on March 30, 2026, but the FDA determined adequacy could not be assessed due to missing timelines, revised procedures, and retrospective review summaries. Peer compliance officers in medical device manufacturing should monitor whether Linemaster provides revised documentation within 30 days and track whether corrective actions address the 2013 sensor-drift issue and the pattern of failed customer calibrations observed between 2023-2025.
Severity context
Critical severity. Typically reserved for data integrity, sterile-product CGMP, or repeat violations — matters that historically precede injunctions, consent decrees, or import alerts.
Regulatory background
CGMP citations typically reference 21 CFR Part 211 (drugs) or 21 CFR Part 600 (biologics). Common subjects include identity testing of incoming components (211.84), validated cleaning procedures (211.67), and stability program design (211.166).
What peer compliance teams typically do next
Most compliance officers at peer companies use a Warning Letter against a named entity as a checklist for their own CAPA program. Common steps: pull the verbatim FDA letter; map each cited 21 CFR section against the team’s SOP library; confirm CAPA coverage; brief the QMR (Quality Management Review) on whether the cited subject matter is in scope for the next internal audit. The 15-business-day response window applies to the cited entity, not to peers — but a documented internal review against the cited subjects is what regulators expect to see if a peer is later inspected on the same topic.
Excerpt from the FDA Warning Letter (public domain, 17 USC §105)
WARNING LETTER Linemaster Switch Corporation MARCS-CMS 730215 — May 27, 2026 More Warning Letters Warning Letters About Warning and Close-Out Letters Delivery Method: VIA Electronic Mail Product: Medical Devices Recipient: Recipient Name Joseph Carlone Jr. Recipient Title President and CEO Linemaster Switch Corporation 29 Plaine Hill Road Woodstock , CT 06281 United States (b)(6), (b)(7)(C) Issuing Office: Center for Devices and Radiological Health United States WARNING LETTER CMS #730215 May 27, 2026 Dear Mr. Carlone: During an inspection of your firm located in Woodstock, CT from February 4, 2026, through March 6, 2026, an investigator from the United States Food and Drug Administration (FDA) determined that your firm manufactures foot pedal accessories for medical devices, including Class II foot pedal controls used with Class IV medical lasers. Under section 201(h) of the Federal Food, Drug, and Cosmetic Act (the Act), 21 U.S.C. § 321(h), these products are devices because they are intended for use in the diagnosis of disease or other conditions or in the cure, mitigation, treatment, or prevention of disease, or to affect the structure or any function of the body. Quality Management System Regulation Violation(s) This inspection revealed that these devices are adulterated within the meaning of section 501(h) of the Act, 21 U.S.C. § 351(h), in that the methods used in, or the facilities or controls used for, their manufacture, packing, storage, or installation are not in conformity with the current good manufacturing practice requirements of the Quality Management System Regulation found at Title 21, Code of Federal Regulations (CFR), Part 820. We received your response dated March 30, 2026, concerning our investigator’s observations noted on the Form FDA 483 (FDA 483), List of Inspectional Observations, that was issued to your firm. We address this response below, in relation to each of the noted violations. These violations include, but are not limited to, the following: 1. Failure to perform rework in accordance with documented procedures that take into account the potential adverse effect of the rework on the product, as required by ISO 13485:2016, Clause 8.3.4. Specifically, your firm did not implement their procedure, Q 006 Rev D3, Nonconforming Material Control, dated October 14, 2025. For example: Section 7.6 of the procedure states "Rework and repair instructions shall be documented on the MRR or a Nonconforming Material Rework/Repair Request form Q6-12 with specific Manufacturing and Inspection Instructions recorded." Rework was not documented when nonconforming units were identified. During the manufacture of Job (b)(4) , the Manufacturing Manager explained that Job (b)(4) , which consisted of (b)(4) units of (b)(4) (part number (b)(4) ) foot pedals had nonconforming product and was being reworked because after calibration, the assembler had failed to (b)(4) screws. The supervisor had the assembler perform rework to apply torque and…
Excerpt only. The full verbatim Warning Letter is the source of truth — always read the original before regulatory decisions.
The verbatim FDA Warning Letter is the source of truth. Always read the original before acting on any analysis or summary on this page.
Read the full letter on fda.gov ↗Frequently asked questions
- What is the standard FDA response window for a warning letter?
- FDA warning letters typically require a written response within 15 working days of receipt, outlining the corrective and preventive actions the company will take.
- Has Linemaster Switch Corporation had FDA enforcement actions before?
- This is the only FDA Warning Letter Argus HQ has on file for Linemaster Switch Corporation as of 2026-07-22. Argus ingests new FDA enforcement records daily.
- What FDA violations was Linemaster Switch Corporation cited for?
- The FDA Warning Letter to Linemaster Switch Corporation (issuing office: Center for Devices and Radiological Health) cites: CGMP/QSR/Drug/Medical Devices/Adulterated. Classification: CGMP — Current Good Manufacturing Practice.
- When did FDA issue the warning letter to Linemaster Switch Corporation?
- FDA issued the letter (MARCS-CMS 730215) on 2026-05-27 and posted it publicly on fda.gov on 2026-07-22.
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methodology
The analysis above is produced by Anthropic Claude Haiku 4.5 against the verbatim FDA Warning Letter excerpt and is brand-voice lint-checked before publish. The TL;DR is the same summary that ships in the customer email digest. Severity is auto-classified by Argus from the subject string and letter body using rules documented in lib/ingestion/fda-warning-letters.ts.
Argus HQ is informational only. Summaries and analyses are AI-generated and may contain errors, misclassifications, or omissions. Verify against the FDA source URL above. Argus HQ is not a law firm, accounting firm, or regulatory agency, and provides no legal, accounting, financial, medical, or regulatory advice.
Compiled by Argus HQ Research from FDA primary sources · Reviewed by Andy Gaber, Founder
Cite this record
Reusing this data in reporting or research? Here’s a ready-made citation.
Argus HQ Research (2026). FDA Cites Linemaster Switch Corporation in 2026-05-27 Warning Letter — CGMP/QSR/Drug/Medical Devices/Adulterated. Digital Empire Holdings LLC. Retrieved from https://argushq.ai/fda/warning-letter/fda-wl-linemaster-switch-corporation-2026-05-27-cgmp
"FDA Cites Linemaster Switch Corporation in 2026-05-27 Warning Letter — CGMP/QSR/Drug/Medical Devices/Adulterated." Argus HQ Research, Digital Empire Holdings LLC, 2026, argushq.ai/fda/warning-letter/fda-wl-linemaster-switch-corporation-2026-05-27-cgmp.
Argus HQ Research. "FDA Cites Linemaster Switch Corporation in 2026-05-27 Warning Letter — CGMP/QSR/Drug/Medical Devices/Adulterated." Digital Empire Holdings LLC. Accessed July 24, 2026. https://argushq.ai/fda/warning-letter/fda-wl-linemaster-switch-corporation-2026-05-27-cgmp.
@misc{argushq_argushq_ai_fda_warning_letter_fda_wl_linemaster_switch_corporation_2026_05_27_cgmp_2026,
title = {FDA Cites Linemaster Switch Corporation in 2026-05-27 Warning Letter — CGMP/QSR/Drug/Medical Devices/Adulterated},
author = {{Argus HQ Research}},
year = {2026},
publisher = {Digital Empire Holdings LLC},
url = {https://argushq.ai/fda/warning-letter/fda-wl-linemaster-switch-corporation-2026-05-27-cgmp},
note = {Accessed: July 24, 2026}
}