# California SB 53

**Type:** State AI safety legislation  
**Status:** Effective January 1, 2026  
**Jurisdiction:** California, United States

## Overview

California SB 53 is state-level frontier AI safety legislation that applies to developers of frontier AI models. The law establishes requirements for incident reporting, safety and security model evaluations, internal governance practices, and whistleblower protections.

## Key Provisions

**Scope:** Applies to developers of frontier AI models operating in California.

**Requirements:**
- Incident reporting obligations
- Safety and security model evaluations
- Internal governance practices
- Whistleblower protections

**External Evaluation:** Voluntary (not mandatory) under SB 53. The law accepts ISO/IEC 42001 (management system standard) as compliance evidence.

## Limitations

METR's regulatory reference identifies two key limitations:
1. Voluntary third-party evaluation structure (identified as inadequate)
2. ISO/IEC 42001 acceptance creates self-reporting architecture

Both limitations were noted as previously identified in prior analysis as inadequate for meaningful safety governance.

## Timeline

- **2026-01-01** — SB 53 becomes effective, establishing California as first US state with frontier AI safety requirements