Almeida Law Group is investigating a data breach at Kurt J. Lesker Company. If you were affected, contact Almeida Law Group.
About Kurt J. Lesker Company
Kurt J. Lesker Company is a privately held, family-owned global manufacturer and distributor of vacuum technology products, thin film deposition systems, and precision components. Founded in 1954, the company is headquartered in Jefferson Hills, Pennsylvania, just south of Pittsburgh, and operates offices in the US, UK, Germany, and China. It employs more than 400 people and serves customers in the semiconductor, aerospace, optics, electronics, medical device, and research markets. Because the company employs a substantial workforce across multiple countries, it collects and retains employee personal information, including Social Security Numbers, which were confirmed as part of this breach.
What Happened?
Kurt J. Lesker Company was listed in a Vermont Attorney General breach report summary dated September 16th, 2026. The filing, which classifies the company as an Other Commercial organization, confirms that Social Security Numbers were among the categories of data involved. A separate notification to Massachusetts residents was dated September 11th, 2026. The total number of persons affected was not specified in the available filings.
The breach is linked to a ransomware attack. Around December 2nd, 2025, the CHAOS ransomware group claimed responsibility on its dark web portal, alleging it had stolen 615 GB of internal data. According to the attacker’s listing, the stolen dataset purportedly included corporate documents, engineering materials, manufacturing records, operational data, and customer-related information. These are attacker allegations and have not been confirmed by the company. Notably, the state breach notifications came approximately nine to ten months after the ransomware group’s public claim, a gap that may be significant for affected individuals. As of September 2026, Srourian Law Firm publicly announced it was investigating a potential class action lawsuit related to the incident, though no filed class action has been confirmed.
Key Facts at a Glance
- Company or Organization: Kurt J. Lesker Company
- Industry: Industrial Machinery Manufacturing / Vacuum Technology / Semiconductor Equipment
- Location: Jefferson Hills, Pennsylvania
- Incident type: Ransomware attack (CHAOS ransomware group); personal data breach
- Date of breach: Around December 2nd, 2025 (per attacker’s public claim; not independently confirmed by the company)
- Date of consumer notification: September 11th, 2026 (Massachusetts); September 16th, 2026 (Vermont)
- Data exposed: Social Security Numbers
- Litigation status: Srourian Law Firm announced a potential class action investigation in December 2025; no filed class action confirmed as of September 2026
- Source: Vermont Attorney General breach report summary; BotCrawl – Kurt J. Lesker Company Data Breach; Srourian Law Firm – Chaos Ransomware Investigation; Class Action U – Current Data Breaches
What Should You Do?
If you received a notice from Kurt J. Lesker Company, review it carefully for details about any identity theft protection being offered and enroll before any stated deadline. Because Social Security Numbers were involved, consider placing a fraud alert or a credit freeze with the three major credit bureaus—Equifax, Experian, and TransUnion—to help prevent new accounts from being opened in your name. Monitor your existing financial accounts and credit reports closely for any unfamiliar activity. You can obtain free copies of your credit reports at AnnualCreditReport.com. If you suspect your information has already been misused, visit IdentityTheft.gov for step-by-step guidance on reporting and recovery.
Your Legal Rights
If your personal information was involved in this breach, you may have legal rights depending on the facts of the incident and the law in your state. Almeida Law Group represents consumers in data breach and privacy litigation and can help you evaluate whether you may have a claim. Contact us at (708) 529-5418 or through our contact page for a free case evaluation.
