diff --git a/README.md b/README.md
index e162085bf..53681726f 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,7 @@ Registers an Amazon ECS task definition and deploys it to an ECS service.
 
 See [action.yml](action.yml) for the full documentation for this action's inputs and outputs.
 In most cases when running a one-off task, subnet ID's, subnet groups, and assign public IP will be required. 
+Assign public IP will only be applied when a subnet or security group is defined. 
 
 ### Task definition file
 
@@ -269,7 +270,8 @@ In the following example, the service would not be updated until the ad-hoc task
         wait-for-task-stopped: true
 ```
 
-Overrides and VPC networking options are available as well. See [action.yml](action.yml) for more details.
+Overrides and VPC networking options are available as well. See [action.yml](action.yml) for more details. The `FARGATE` 
+launch type requires `awsvpc` network mode in your task definition and you must specify a network configuration.
 
 ## Troubleshooting
 
diff --git a/action.yml b/action.yml
index 0a4cde074..29ecf22fb 100644
--- a/action.yml
+++ b/action.yml
@@ -53,7 +53,7 @@ inputs:
     description: 'A comma-separated list of subnet IDs to assign to a task when run outside of a service. Will default to none.'
     required: false
   run-task-assign-public-IP:
-    description: "Whether the task's elastic network interface receives a public IP address. The default value is DISABLED."
+    description: "Whether the task's elastic network interface receives a public IP address. The default value is DISABLED but will only be applied if run-task-subnets or run-task-security-groups are also set."
     required: false
   run-task-launch-type:
     description: "ECS launch type for tasks run outside of a service. Valid values are 'FARGATE' or 'EC2'. Will default to 'FARGATE'."
diff --git a/dist/index.js b/dist/index.js
index b3db50d86..8317024be 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -48,10 +48,10 @@ async function runTask(ecs, clusterName, taskDefArn, waitForMinutes) {
     awsvpcConfiguration["securityGroups"] = securityGroupIds.split(',')
   }
 
-  if(assignPublicIP != ""){
+  if(assignPublicIP != "" && (subnetIds != "" || securityGroupIds != "")){
     awsvpcConfiguration["assignPublicIp"] = assignPublicIP
   }
-  
+
   const runTaskResponse = await ecs.runTask({
     startedBy: startedBy,
     cluster: clusterName,
@@ -60,7 +60,7 @@ async function runTask(ecs, clusterName, taskDefArn, waitForMinutes) {
       containerOverrides: containerOverrides
     },
     launchType: launchType,
-    networkConfiguration: Object.keys(awsvpcConfiguration).length === 0 ? {} : { awsvpcConfiguration: awsvpcConfiguration }
+    networkConfiguration: Object.keys(awsvpcConfiguration).length === 0 ? null : { awsvpcConfiguration: awsvpcConfiguration }
   });
 
   core.debug(`Run task response ${JSON.stringify(runTaskResponse)}`)
diff --git a/index.js b/index.js
index aa8960836..8a7027330 100644
--- a/index.js
+++ b/index.js
@@ -42,10 +42,10 @@ async function runTask(ecs, clusterName, taskDefArn, waitForMinutes) {
     awsvpcConfiguration["securityGroups"] = securityGroupIds.split(',')
   }
 
-  if(assignPublicIP != ""){
+  if(assignPublicIP != "" && (subnetIds != "" || securityGroupIds != "")){
     awsvpcConfiguration["assignPublicIp"] = assignPublicIP
   }
-  
+
   const runTaskResponse = await ecs.runTask({
     startedBy: startedBy,
     cluster: clusterName,
@@ -54,7 +54,7 @@ async function runTask(ecs, clusterName, taskDefArn, waitForMinutes) {
       containerOverrides: containerOverrides
     },
     launchType: launchType,
-    networkConfiguration: Object.keys(awsvpcConfiguration).length === 0 ? {} : { awsvpcConfiguration: awsvpcConfiguration }
+    networkConfiguration: Object.keys(awsvpcConfiguration).length === 0 ? null : { awsvpcConfiguration: awsvpcConfiguration }
   });
 
   core.debug(`Run task response ${JSON.stringify(runTaskResponse)}`)
diff --git a/index.test.js b/index.test.js
index 5cf74ae09..95bb51330 100644
--- a/index.test.js
+++ b/index.test.js
@@ -1129,7 +1129,7 @@ describe('Deploy to ECS', () => {
             launchType: 'FARGATE',
             taskDefinition: 'task:def:arn',
             overrides: {"containerOverrides": []},
-            networkConfiguration: {awsvpcConfiguration: {assignPublicIp: "DISABLED" }}
+            networkConfiguration: null
         });
 
         expect(core.setOutput).toHaveBeenNthCalledWith(2, 'run-task-arn', ["arn:aws:ecs:fake-region:account_id:task/arn"]);
@@ -1236,6 +1236,36 @@ describe('Deploy to ECS', () => {
         expect(waitUntilTasksStopped).toHaveBeenCalledTimes(1);
     });
 
+    test('run task in bridge network mode', async () => {
+        core.getInput = jest
+            .fn()
+            .mockReturnValueOnce('task-definition.json')  // task-definition
+            .mockReturnValueOnce('service-456')           // service
+            .mockReturnValueOnce('somecluster')           // cluster
+            .mockReturnValueOnce('true')                  // wait-for-service-stability
+            .mockReturnValueOnce('')                      // wait-for-minutes
+            .mockReturnValueOnce('')                      // force-new-deployment
+            .mockReturnValueOnce('')                      // desired-count
+            .mockReturnValueOnce('true')                  // run-task
+            .mockReturnValueOnce('true')                  // wait-for-task-stopped
+            .mockReturnValueOnce('someJoe')               // run-task-started-by
+            .mockReturnValueOnce('EC2')                   // run-task-launch-type
+            .mockReturnValueOnce('')                      // run-task-subnet-ids
+            .mockReturnValueOnce('')                      // run-task-security-group-ids
+            .mockReturnValueOnce('')                      // run-task-container-overrides
+            .mockReturnValueOnce('')                      // run-task-assign-public-IP
+
+        await run();
+        expect(mockRunTask).toHaveBeenCalledWith({
+            startedBy: 'someJoe',
+            cluster: 'somecluster',
+            taskDefinition: 'task:def:arn',
+            launchType: 'EC2',
+            overrides: { containerOverrides: [] },
+            networkConfiguration: null
+        });
+    });
+
     test('error is caught if run task fails with (wait-for-task-stopped: true)', async () => {
         core.getInput = jest
         .fn()