diff --git a/examples/workflow-server/src/common/workflow-edge-creation-checker.ts b/examples/workflow-server/src/common/workflow-edge-creation-checker.ts
index da45ef4..6addee0 100644
--- a/examples/workflow-server/src/common/workflow-edge-creation-checker.ts
+++ b/examples/workflow-server/src/common/workflow-edge-creation-checker.ts
@@ -21,7 +21,7 @@ import { ModelTypes } from './util/model-types';
 @injectable()
 export class WorkflowEdgeCreationChecker implements EdgeCreationChecker {
     isValidSource(edgeType: string, sourceElement: GModelElement): boolean {
-        return edgeType !== ModelTypes.WEIGHTED_EDGE && sourceElement.type === ModelTypes.DECISION_NODE;
+        return edgeType === ModelTypes.WEIGHTED_EDGE && sourceElement.type === ModelTypes.DECISION_NODE;
     }
     isValidTarget(edgeType: string, sourceElement: GModelElement, targetElement: GModelElement): boolean {
         return (