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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
Charles River LaboratoriesSuite 200 South San Francisco, CA55Sep 19, 2023Jul 19, 2023closureSource ↗
Alto Operations CaliforniaSuite 150 Belmont, CA34Sep 15, 2023Jul 14, 2023closureSource ↗
IlluminaSan Mateo, CA14Aug 14, 2023Jul 13, 2023layoffSource ↗
Robinhood MarketsSan Mateo, CA23Sep 1, 2023Jun 29, 2023layoffSource ↗
Proterra OperatingSan Mateo, CA48Jul 28, 2023Jun 27, 2023layoffSource ↗
Thermo Fisher ScientificSan Mateo, CA64Aug 22, 2023Jun 22, 2023layoffSource ↗
IlluminaSan Mateo, CA71Jul 21, 2023Jun 21, 2023layoffSource ↗
AmgenSuite 600 San Carlos, CA4Sep 1, 2023Jun 13, 2023closureSource ↗
Sumo LogicSuite 100 Redwood City, CA79Jun 8, 2023Jun 7, 2023layoffSource ↗
Robinhood MarketsSan Mateo, CA7Jul 31, 2023Jun 3, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA5Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA40Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA40Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA45Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA58Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA5Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA14Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA4Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA17Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA58Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA3Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA8Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA68Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA89Jul 28, 2023May 29, 2023layoffSource ↗
Meta PlatformsSan Mateo, CA7Jul 28, 2023May 29, 2023layoffSource ↗

581 notices · Source check Oct 9, 2026

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