diff --git a/frontend/src/app/components/medical-sources-connected/medical-sources-connected.component.ts b/frontend/src/app/components/medical-sources-connected/medical-sources-connected.component.ts
index 9df8aac4..3b753f28 100644
--- a/frontend/src/app/components/medical-sources-connected/medical-sources-connected.component.ts
+++ b/frontend/src/app/components/medical-sources-connected/medical-sources-connected.component.ts
@@ -155,8 +155,18 @@ export class MedicalSourcesConnectedComponent implements OnInit {
             //remove the "Patient/" or "https://example.com/fhir/Patient/" prefix if it exists
             payload.patient = payload.patient.split("Patient/")[1]
           }
-
         }
+        //special case for flatiron id token. See https://github.com/fastenhealth/fasten-sources/issues/42
+        if(!payload.patient && sourceMetadata.platform_type == 'flatiron'){
+          // "pp.patient_id": "PD_05XXXXXXXXX3",
+          // "pp.group_id": "GH_CXXXXXXXXXXXX9_5",
+          // Becomes: PD--05XXXXXXXXX3.GH--CXXXXXXXXXXXX9--5
+
+          let decodedAccessToken = this.jwtDecode(payload.access_token)
+          let patientId = `${decodedAccessToken["pp.patient_id"]}.${decodedAccessToken["pp.group_id"]}`.replace(/_/g, '--')
+          payload.patient = patientId
+        }
+
 
         //get the portal information
         const portalInfo = await this.lighthouseApi.getLighthouseCatalogPortal(expectedSourceStateInfo.portal_id)
diff --git a/frontend/src/app/services/lighthouse.service.ts b/frontend/src/app/services/lighthouse.service.ts
index 6c2f3ba1..9eaf42bc 100644
--- a/frontend/src/app/services/lighthouse.service.ts
+++ b/frontend/src/app/services/lighthouse.service.ts
@@ -120,6 +120,8 @@ export class LighthouseService {
   }
 
 
+  //DEPRECATED
+  // TODO: use the fasten-sources js library
   async generateSourceAuthorizeUrl(lighthouseSource: LighthouseSourceMetadata, reconnectSourceId?: string): Promise<URL> {
     const state = uuidV4()
     let sourceStateInfo = new SourceState()