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SEC Issues Enforcement Guidance Update for Cyber Incident Disclosure Rule
New staff guidance clarifies materiality timing and what counts as a determination event under Item 1.05.
By Priya Natarajan Apr 28, 2026 4 min readLast updated May 1, 2026
The U.S. Securities and Exchange Commission has released updated staff guidance refining how registrants should interpret the materiality determination timeline under Item 1.05.
Key Clarifications
- The 4-business-day clock starts at materiality determination, not at incident detection.
- Ongoing investigations do not pause the disclosure obligation once materiality is reached.
- Registrants should document the materiality assessment process contemporaneously.
What GRC Teams Should Do
Update incident response playbooks to include a defined materiality assessment step with named decision-makers and templated documentation.
Sources
- SEC.gov · SEC
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