diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1d6b2eb..3d0b725 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -111,7 +111,7 @@ jobs:
         - if: steps.approved-by-required-users.outcome != 'failure' || steps.approved-by-required-users.outputs.maintainer-approvals != 'peternied'
           run: echo "Unexpected outcome:${{ steps.approved-by-required-users.outcome }} or maintainer-approvals:${{steps.approved-by-required-users.outputs.maintainer-approvals}}"
 
-  test-approved-by-anyone:
+  test-no-required-approvers-list:
     runs-on: ubuntu-latest
     steps:
         - uses: actions/checkout@v4
@@ -124,5 +124,5 @@ jobs:
             mock-approvers: 'peternied bob kelly'
             mock-pr-number: 42
         
-        - if: steps.approved-by-required-users.outcome != 'failure' || steps.approved-by-required-users.outputs.maintainer-approvals != 'peternied bob kelly'
+        - if: steps.approved-by-required-users.outcome != 'success' || steps.approved-by-required-users.outputs.maintainer-approvals != 'peternied bob kelly'
           run: echo "Unexpected outcome:${{ steps.approved-by-required-users.outcome }} or maintainer-approvals:${{steps.approved-by-required-users.outputs.maintainer-approvals}}"
diff --git a/README.md b/README.md
index 8613c04..ed1d4b1 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ inputs:
     required: true
   required-approvers-list:
     description: 'The list of specific users that can approve the request, comma seperated. '
-    required: false
+    required: true
   min-required:
     description: 'The minimum number of approvals, e.g. 2'
     required: true
@@ -24,9 +24,6 @@ outputs:
 ```yaml
 on:
   pull_request_review:
-    types: [approved]
-  pull_request_target:
-    types: [opened, reopened]
 ...
 steps:
 - id: list-maintainers
diff --git a/action.yml b/action.yml
index 446cc95..b725204 100644
--- a/action.yml
+++ b/action.yml
@@ -12,7 +12,7 @@ inputs:
     required: true
   required-approvers-list:
     description: 'The list of specific users that can approve the request, comma separated. '
-    required: false
+    required: true
   min-required:
     description: 'The minimum number of approvals, e.g. 2'
     required: true
diff --git a/dist/index.js b/dist/index.js
index d7f78e1..0d488e1 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -36730,7 +36730,7 @@ async function run() {
     return;
   }
 
-  const requiredApprovers = core.getInput('required-approvers-list', { required: false })?.split(',').map(s => s.trim()) || [];
+  const requiredApprovers = core.getInput('required-approvers-list', { required: true })?.split(',').map(s => s.trim()).filter(a => a.length != 0);
   const mockApprovers = core.getInput('mock-approvers', { required: false })?.split(' ') || [];
 
   let pullRequestApprovers = mockApprovers;
diff --git a/index.js b/index.js
index d4deaaa..7a91315 100644
--- a/index.js
+++ b/index.js
@@ -21,7 +21,7 @@ async function run() {
     return;
   }
 
-  const requiredApprovers = core.getInput('required-approvers-list', { required: false })?.split(',').map(s => s.trim()) || [];
+  const requiredApprovers = core.getInput('required-approvers-list', { required: true })?.split(',').map(s => s.trim()).filter(a => a.length != 0);
   const mockApprovers = core.getInput('mock-approvers', { required: false })?.split(' ') || [];
 
   let pullRequestApprovers = mockApprovers;