diff --git a/ontology_platform/web/frontend/src/lib/api/crawl.ts b/ontology_platform/web/frontend/src/lib/api/crawl.ts
index 9130870..02f9445 100644
--- a/ontology_platform/web/frontend/src/lib/api/crawl.ts
+++ b/ontology_platform/web/frontend/src/lib/api/crawl.ts
@@ -94,7 +94,7 @@ export const extractorModelsResponseSchema = z.object({
       z
         .object({
           id: z.string(),
-          owned_by: z.string().optional(),
+          owned_by: z.string().nullish(),
         })
         .passthrough(),
     )