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San Mateo County, California WARN notices

San Mateo County, California has 581 non-cancelled imported WARN notices reporting 46,943 workers affected. 6 notices have future effective dates. These totals cover imported records only.

What the official notice history shows

During the last 365 days, this imported archive contains 47 eligible official filings for San Mateo County, California, reporting 6,121 affected workers. 0 worker counts are unavailable. The newest official notice date is Sep 14, 2026.

580 non-cancelled direct government records and 1 attributed secondary records appear in the full archive. Recent official event types: layoff, closure. These figures describe notices, not unique people or completed layoffs. Grouped company names do not establish ownership.

Compare original weekly and monthly official-data reports → · How dates, names and counts are interpreted

581Non-cancelled notices
46,943Reported workers
6Future effective dates
Coverage is limited to connected sources and imported date ranges. 0 notices have unavailable worker counts. Company groups match normalized names; aliases below preserve exact employer names from filings. Methodology →

Notice history by year

202638 notices · 5,521 reported workers
202562 notices · 3,309 reported workers
202448 notices · 3,865 reported workers
2023129 notices · 5,388 reported workers
202244 notices · 4,115 reported workers
202142 notices · 2,917 reported workers
2020170 notices · 18,271 reported workers
201923 notices · 1,595 reported workers
201817 notices · 1,372 reported workers
20177 notices · 515 reported workers
20161 notices · 75 reported workers
Oracle America →California →Redwood City →LeeMAH Electronics →Brisbane →Arsenal Biosciences →South San Francisco →Cellares →FLYING FOOD GROUP →Burlingame →Visa →Foster City →Yerba Mate Co., LLC - South San Francisco →Flagship Facilities Services →Genentech →

Filings and attributed reports

Company / locationWorkersEffective dateNotice dateType / source
Meta PlatformsSan Mateo, CA1Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA47Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA4Jul 28, 2023May 29, 2023layoffSource ↗
Twist BioscienceSan Mateo, CA10Jul 3, 2023May 4, 2023layoffSource ↗
Twist BioscienceSan Mateo, CA197Jul 3, 2023May 4, 2023layoffSource ↗
Cala HealthSan Mateo, CA107Jun 30, 2023May 1, 2023layoffSource ↗
Summit Public SchoolsSan Mateo, CA2Jun 30, 2023Apr 28, 2023layoffSource ↗
Summit Public SchoolsSan Mateo, CA3Jun 30, 2023Apr 28, 2023layoffSource ↗
Summit Public SchoolsSan Mateo, CA29Jun 30, 2023Apr 28, 2023layoffSource ↗
Cushman & Wakefield U.S.San Mateo, CA2Jun 25, 2023Apr 27, 2023layoffSource ↗
Sangamo TherapeuticsSan Mateo, CA30Jun 26, 2023Apr 26, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA32Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA70Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA30Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA35Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA57Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA40Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA44Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA79Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA53Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA27Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA91Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA114Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA25Jun 23, 2023Apr 24, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA42Jun 23, 2023Apr 24, 2023layoffSource ↗

581 notices · Source check Oct 9, 2026

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