Location: South San Francisco, CA (San Mateo County).
A WARN notice was filed on September 16, 2025.
Disclosed through an official WARN filing with the CA state workforce agency.
Arsenal Biosciences, Inc. disclosed this layoff in an official WARN (Worker Adjustment and Retraining Notification) notice filed with the CA state workforce agency on September 16, 2025. The notice covers 100 employees in South San Francisco, CA (San Mateo County), with the layoff effective November 14, 2025.
LayoffTalk has tracked 4 layoff events at Arsenal Biosciences, Inc. since October 2023, affecting a combined 300 employees.
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Arsenal Biosciences, Inc. cut 100 jobs in South San Francisco, CA on November 14, 2025. Were you affected, or do you know people who were? How was it handled — severance, notice, which teams? You can post anonymously below.
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