diff --git a/lib/actions/upload-actions.js b/lib/actions/upload-actions.js
--- a/lib/actions/upload-actions.js
+++ b/lib/actions/upload-actions.js
@@ -177,10 +177,20 @@
     const { uploadInput, callbacks, keyserverOrThreadID } = input;
     const { encryptionKey, loop, dimensions, thumbHash, blobInput } =
       uploadInput;
-    const blobHolder = generateBlobHolder(authMetadata.deviceID);
     const blobHash = toBase64URL(uploadInput.blobHash);
     const defaultHeaders = createDefaultHTTPRequestHeaders(authMetadata);
 
+    let maybeKeyserverID;
+    if (keyserverOrThreadID) {
+      maybeKeyserverID =
+        extractKeyserverIDFromIDOptional(keyserverOrThreadID) ??
+        keyserverOrThreadID;
+    }
+
+    // don't prefix keyserver-owned holders with deviceID
+    const holderPrefix = maybeKeyserverID ? null : authMetadata.deviceID;
+    const blobHolder = generateBlobHolder(holderPrefix);
+
     // 1. Assign new holder for blob with given blobHash
     let blobAlreadyExists: boolean;
     try {
@@ -239,12 +249,6 @@
     }
 
     // 3. Optionally upload metadata to keyserver
-    let maybeKeyserverID;
-    if (keyserverOrThreadID) {
-      maybeKeyserverID =
-        extractKeyserverIDFromIDOptional(keyserverOrThreadID) ??
-        keyserverOrThreadID;
-    }
     const mimeType =
       blobInput.type === 'file' ? blobInput.file.type : blobInput.mimeType;