diff --git a/.github/workflows/pr-commit-check.yml b/.github/workflows/pr-commit-check.yml
index bd989b1d48..a2820a8fcf 100644
--- a/.github/workflows/pr-commit-check.yml
+++ b/.github/workflows/pr-commit-check.yml
@@ -27,15 +27,35 @@ jobs:
           fail=0
           while IFS= read -r sha; do
             [ -z "$sha" ] && continue
-            if git log -1 --format=%B "$sha" | git interpret-trailers --parse | \
-               grep -iE '^(Co-authored-by|Signed-off-by):.*<?noreply@anthropic\.com>?' >/dev/null; then
-              echo "::error::Commit $sha contains a Co-authored-by or Signed-off-by trailer for noreply@anthropic.com"
+            trailers=$(git log -1 --format=%B "$sha" | git interpret-trailers --parse)
+            if echo "$trailers" | \
+               grep -iE '^(Co-authored-by|Signed-off-by):.*<?noreply@(anthropic|openai)\.com>?[[:space:]]*$' >/dev/null; then
+              echo "::error::Commit $sha contains a Co-authored-by or Signed-off-by trailer for a disallowed AI vendor"
+              git log -1 --format='  %h %s' "$sha"
+              fail=1
+            fi
+            if echo "$trailers" | \
+               grep -iE '^(Co-authored-by|Signed-off-by):.*<?[0-9]+\+Copilot@users\.noreply\.github\.com>?[[:space:]]*$' >/dev/null; then
+              echo "::error::Commit $sha contains a Co-authored-by or Signed-off-by trailer for GitHub Copilot"
+              git log -1 --format='  %h %s' "$sha"
+              fail=1
+            fi
+            if echo "$trailers" | \
+               grep -iE '^(Co-authored-by|Signed-off-by):.*\[bot\]@users\.noreply\.github\.com>?[[:space:]]*$' >/dev/null; then
+              echo "::error::Commit $sha contains a Co-authored-by or Signed-off-by trailer for a bot account"
+              git log -1 --format='  %h %s' "$sha"
+              fail=1
+            fi
+            author_email=$(git log -1 --format=%ae "$sha")
+            if echo "$author_email" | \
+               grep -iE '\[bot\]@users\.noreply\.github\.com$' >/dev/null; then
+              echo "::error::Commit $sha is authored by a bot account ($author_email)"
               git log -1 --format='  %h %s' "$sha"
               fail=1
             fi
           done < <(git rev-list "$BASE_SHA".."$HEAD_SHA")
           if [ "$fail" -ne 0 ]; then
-            echo "One or more commits contain disallowed AI attribution trailers; please amend them out."
+            echo "One or more commits contain disallowed AI attribution; please amend them out."
             exit 1
           fi
-          echo "No disallowed AI attribution trailers found."
+          echo "No disallowed AI attribution found."