diff --git a/dashboards-reports/server/utils/__tests__/validationHelper.test.ts b/dashboards-reports/server/utils/__tests__/validationHelper.test.ts
index 692d9fe4..cacd3d61 100644
--- a/dashboards-reports/server/utils/__tests__/validationHelper.test.ts
+++ b/dashboards-reports/server/utils/__tests__/validationHelper.test.ts
@@ -65,6 +65,32 @@ const createReportInput: ReportSchemaType = {
   report_definition: createReportDefinitionInput,
 };
 
+// this is the url format used before notebooks merged into observability
+const createReportDefinitionNotebookLegacyInput: ReportDefinitionSchemaType = {
+  report_params: {
+    report_name: 'test notebooks report',
+    report_source: REPORT_TYPE.notebook,
+    description: 'Hi this is your Notebook on demand',
+    core_params: {
+      base_url: `/app/notebooks-dashboards?view=output_only#/${SAMPLE_SAVED_OBJECT_ID}`,
+      window_width: 1300,
+      window_height: 900,
+      report_format: FORMAT.pdf,
+      time_duration: 'PT5M',
+      origin: 'http://localhost:5601',
+    },
+  },
+  delivery: {
+    configIds: [],
+    title: 'title',
+    textDescription: 'text description',
+    htmlDescription: 'html description'
+  },
+  trigger: {
+    trigger_type: TRIGGER_TYPE.onDemand,
+  },
+}
+
 const createReportDefinitionNotebookInput: ReportDefinitionSchemaType = {
   report_params: {
     report_name: 'test notebooks report',
@@ -118,6 +144,16 @@ describe('test input validation', () => {
     expect(report).toBeDefined();
   });
 
+  test('create notebook report definition with legacy base url format', async () => {
+    const savedObjectIds = [`notebook:${SAMPLE_SAVED_OBJECT_ID}`];
+    const client = mockOpenSearchClient(savedObjectIds);
+    const report = await validateReportDefinition(
+      client,
+      createReportDefinitionNotebookLegacyInput
+    );
+    expect(report).toBeDefined();
+  });
+
   test('create notebook report definition with correct base url format', async () => {
     const savedObjectIds = [`notebook:${SAMPLE_SAVED_OBJECT_ID}`];
     const client = mockOpenSearchClient(savedObjectIds);
diff --git a/dashboards-reports/server/utils/validationHelper.ts b/dashboards-reports/server/utils/validationHelper.ts
index 252ac9a1..99e969c7 100644
--- a/dashboards-reports/server/utils/validationHelper.ts
+++ b/dashboards-reports/server/utils/validationHelper.ts
@@ -55,7 +55,7 @@ export const isValidRelativeUrl = (relativeUrl: string) => {
 export const regexDuration = /^(-?)P(?=\d|T\d)(?:(\d+)Y)?(?:(\d+)M)?(?:(\d+)([DW]))?(?:T(?:(\d+)H)?(?:(\d+)M)?(?:(\d+(?:\.\d+)?)S)?)?$/;
 export const regexEmailAddress = /\S+@\S+\.\S+/;
 export const regexReportName = /^[\w\-\s\(\)\[\]\,\_\-+]+$/;
-export const regexRelativeUrl = /^\/(_plugin\/kibana\/|_dashboards\/)?app\/(dashboards|visualize|discover|observability)([?&]security_tenant=.+|)#\/(notebooks\/|view\/|edit\/)?[^\/]+$/;
+export const regexRelativeUrl = /^\/(_plugin\/kibana\/|_dashboards\/)?app\/(dashboards|visualize|discover|observability|notebooks-dashboards\?view=output_only)([?&]security_tenant=.+|)#\/(notebooks\/|view\/|edit\/)?[^\/]+$/;
 
 export const validateReport = async (
   client: ILegacyScopedClusterClient,