diff --git a/apps/server/src/modules/tldraw/service/tldraw.ws.service.ts b/apps/server/src/modules/tldraw/service/tldraw.ws.service.ts
index af62849cb3f..ff8e379a4e8 100644
--- a/apps/server/src/modules/tldraw/service/tldraw.ws.service.ts
+++ b/apps/server/src/modules/tldraw/service/tldraw.ws.service.ts
@@ -98,7 +98,7 @@ export class TldrawWsService {
 	 * @param {WsSharedDocDo} doc
 	 */
 	public updateHandler(update: Uint8Array, origin, doc: WsSharedDocDo): void {
-		const isOriginWSConn = origin instanceof WebSocket;
+		const isOriginWSConn = doc.conns.has(origin as WebSocket);
 		console.log('Origin: ', origin);
 		console.log('doc.conns: ', doc.conns);
 		console.log('Update Handler, isOriginWSConn: ', isOriginWSConn);