“Very thankful for everything they did for us. Always responsive, reassured us every step of the way and obtained a great result.”
Miguel Orellana
✦ Certified Specialist in Workers’ Compensation Law — Certified by the State Bar of California, Board of Legal Specialization ✦
Serving injured workers across California. Board-certified specialist; no fee unless we win.
By Eman Yazdchi, Esq. · Certified Specialist in Workers' Compensation Law, State Bar of California Board of Legal Specialization
In California, Labor Code §5500.5 places cumulative-trauma liability on the employer(s) during the last year of injurious exposure — the rule that determines which employer pays a CT claim when a worker was exposed at multiple employers. Yazdchi Law handles California §5500.5 cumulative-trauma claims statewide.
California Labor Code §5500.5 establishes the "last-injurious-exposure" rule for California cumulative-trauma claims. The §5500.5 California rule places liability for a CT injury under California Labor Code §3208.1 on the employer or employers during the last year of injurious exposure preceding the California Labor Code §5412 date of injury — not on every employer the worker had during the cumulative exposure period. The §5500.5 California rule is the practical mechanism for assigning CT claim liability when a worker was repetitively exposed at multiple employers over years or decades.
Under California Labor Code §5500.5, a California worker who developed a cumulative-trauma shoulder injury across three employers over 10 years generally files a CT claim against the final employer (or employers) during the year preceding the California Labor Code §5412 date of injury — not against all three. The §5500.5 California rule simplifies CT liability by concentrating it on the last year of exposure. If multiple employers operated during that final year, the §5500.5 California liability is allocated among them.
Under California Labor Code §5412 (date of injury) and California Labor Code §5500.5 (employer liability), the §5412 date triggers the §5500.5 lookback. The §5412 California date of injury for a CT claim is the date the worker first suffered disability AND knew (or with reasonable diligence should have known) the disability was work-related. The §5500.5 California one-year lookback runs from that §5412 date — capturing the employer(s) during the year immediately preceding disability-plus-knowledge.
Under California Labor Code §5500.5 and California Labor Code §3208.1, California cumulative-trauma claims cover slow-developing injuries from repetitive exposure — repetitive-motion injuries (back, shoulder, wrist, knee from lifting, bending, computer use), occupational-disease claims (silicosis, asbestos exposure, chemical sensitization, hearing loss), and stress-induced injuries developing over time. The §5500.5 California rule applies to any CT injury that meets the §3208.1 definition. Traumatic single-event injuries are not §5500.5 California cases — they have a clear injury date and one employer at the time.
Under California Labor Code §5405 (one-year filing statute of limitations) and California Labor Code §5412 (CT date of injury), the §5500.5 California liability framework only matters if the worker timely files a claim under California Labor Code §5405. The §5405 California one-year clock starts running from the §5412 date of injury, and the §5500.5 employer is the defendant. A California worker who waits too long after the §5412 date can lose the right to recover even when a §5500.5 employer would clearly have been liable.
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Tap to call →Last reviewed by Eman Yazdchi, Esq., May 2026.
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