Breaking2026-09
CRM API Write Validation Enforcement
Starting with the 2026-09 API version, HubSpot will enforce admin-configured validation rules on all CRM API write paths. Integrations that create or update CRM records must ensure compliance before updating to this API version.
Starting with the /2026-09/ API version shipping on September 8, 2026, HubSpot will enforce admin-configured validation rules on all CRM API write paths. If your integration creates or updates CRM records, please make sure that it conforms to the below changes before updating your version of the API.
apicrmbreaking-changevalidation
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