diff --git a/.changeset/catalog-backend-permissions-cleanup-step-1.md b/.changeset/catalog-backend-permissions-cleanup-step-1.md
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+---
+'@backstage/plugin-catalog-backend': patch
+---
+
+Removed deprecated `PermissionAuthorizer` support and the `createPermissionIntegrationRouter` fallback path from `CatalogBuilder`. The `permissionsRegistry` service is now required, and `permissions` is always a `PermissionsService`.