diff --git a/src/datasources/db/cargobikeAPI.ts b/src/datasources/db/cargobikeAPI.ts
index 45400fa..39c7645 100644
--- a/src/datasources/db/cargobikeAPI.ts
+++ b/src/datasources/db/cargobikeAPI.ts
@@ -127,6 +127,33 @@ export class CargoBikeAPI extends DataSource {
         }
     }
 
+    async isLocked (id: number, req: any, dataSources: any) {
+        const token = req.headers.authorization?.replace('Bearer ', '');
+        const userId = await dataSources.userAPI.getUserId(token);
+        const lock = await this.connection.getRepository(CargoBike)
+            .createQueryBuilder('cargobike')
+            .select([
+                'cargobike' + '.lockedUntil',
+                'cargobike' + '.lockedBy'
+            ])
+            .where('id = :id', {
+                id: id
+            })
+            .andWhere('cargobike' + '.lockedUntil > CURRENT_TIMESTAMP')
+            .getOne();
+        if (!lock?.lockedUntil) {
+            // no lock
+            return false;
+        // eslint-disable-next-line eqeqeq
+        } else if (lock?.lockedBy == userId) {
+            // user has locked
+            return false;
+        } else {
+            // enity is locked by other user
+            return true;
+        }
+    }
+
     /**
      * Updates CargoBike and return updated cargoBike
      * @param param0 cargoBike to be updated
diff --git a/src/model/Equipment.ts b/src/model/Equipment.ts
index fe675dc..b5a0d57 100644
--- a/src/model/Equipment.ts
+++ b/src/model/Equipment.ts
@@ -49,6 +49,4 @@ export class Equipment implements Lockable {
         nullable: true
     })
     lockedBy: number;
-
-    cargoBikeId: number;
 }
diff --git a/src/resolvers/cargobikeResolver.ts b/src/resolvers/cargobikeResolver.ts
index 731567f..6c01556 100644
--- a/src/resolvers/cargobikeResolver.ts
+++ b/src/resolvers/cargobikeResolver.ts
@@ -51,6 +51,9 @@ export default {
         },
         lendingStation (parent: any, __: any, { dataSources, req }: { dataSources: any, req: any }) {
             return dataSources.lendingStationAPI.lendingStationByCargoBikeId(parent.id);
+        },
+        isLocked (parent: any, __: any, { dataSources, req }: { dataSources: any, req: any }) {
+            return dataSources.cargoBikeAPI.isLocked(parent.id, req, dataSources);
         }
     },
     Equipment: {
diff --git a/src/schema/type-defs.ts b/src/schema/type-defs.ts
index 62f3a47..28a9e02 100644
--- a/src/schema/type-defs.ts
+++ b/src/schema/type-defs.ts
@@ -41,6 +41,7 @@ type CargoBike {
     lendingStation: LendingStation
     taxes: Taxes
     engagement(offset: Int!, limit: Int!): [Engagement]
+    isLocked: Boolean!
     "null if not locked by other user"
     lockedBy: ID
     lockedUntil: Date