diff --git a/lib/js-api/src/api/content-custom-api/api/upload.api.ts b/lib/js-api/src/api/content-custom-api/api/upload.api.ts
index 6d4fd0a349..96aa3903a7 100644
--- a/lib/js-api/src/api/content-custom-api/api/upload.api.ts
+++ b/lib/js-api/src/api/content-custom-api/api/upload.api.ts
@@ -31,7 +31,7 @@ export class UploadApi extends NodesApi {
         const nodeBodyRequired = {
             name: fileDefinition.name,
             nodeType: 'cm:content',
-            relativePath
+            relativePath: relativePath ?? null
         };
 
         nodeBody = Object.assign(nodeBodyRequired, nodeBody);