diff --git a/scripts/desktop_release.py b/scripts/desktop_release.py
index ce9ceaab932..48e7ce86ced 100755
--- a/scripts/desktop_release.py
+++ b/scripts/desktop_release.py
@@ -257,12 +257,15 @@ def validate(args: argparse.Namespace) -> None:
     bad = [str(path.relative_to(ROOT)) for path, value in manifests.items() if value != version]
     if bad:
         raise SystemExit(f"version mismatch in: {', '.join(bad)}")
-    author = git("show", "-s", "--format=%an <%ae>", candidate)
+    name = git("show", "-s", "--format=%an", candidate)
+    email = git("show", "-s", "--format=%ae", candidate)
+    if not name or not email:
+        raise SystemExit("candidate has no author identity")
+    author = f"{name} <{email}>"
     body = git("show", "-s", "--format=%B", candidate)
-    if author != "Wes <wesbillman@users.noreply.github.com>":
-        raise SystemExit(f"unexpected candidate author: {author}")
-    if "Signed-off-by: Wes <wesbillman@users.noreply.github.com>" not in body:
-        raise SystemExit("candidate is missing Wes Signed-off-by trailer")
+    signoffs = re.findall(rf"(?m)^Signed-off-by: {re.escape(author)}$", body)
+    if len(signoffs) != 1:
+        raise SystemExit(f"candidate must carry exactly one Signed-off-by trailer matching its author {author}")
     if not re.search(r"(?m)^Co-authored-by: .+ <.+>$", body):
         raise SystemExit("candidate is missing automation Co-authored-by trailer")
     print(f"validated immutable desktop candidate {candidate} for desktop-v{version}")
diff --git a/scripts/prepare-desktop-release.sh b/scripts/prepare-desktop-release.sh
index 43785075a15..eec08ac8c56 100755
--- a/scripts/prepare-desktop-release.sh
+++ b/scripts/prepare-desktop-release.sh
@@ -42,8 +42,7 @@ chore(release): release Buzz Desktop version $version
 
 Co-authored-by: $agent_name <$agent_email>
 EOF
-git -c user.name='Wes' -c user.email='wesbillman@users.noreply.github.com' \
-  commit -s -F "$msg"
+git commit -s -F "$msg"
 scripts/desktop_release.py validate --candidate HEAD --version "$version" --repo block/buzz
 
 candidate_sha="$(git rev-parse HEAD)"
diff --git a/scripts/test-desktop-release-candidate.sh b/scripts/test-desktop-release-candidate.sh
index c63a157c006..503c64eb37d 100755
--- a/scripts/test-desktop-release-candidate.sh
+++ b/scripts/test-desktop-release-candidate.sh
@@ -64,8 +64,42 @@ for path in ('desktop/package.json', 'desktop/src-tauri/tauri.conf.json'):
 open('desktop/src-tauri/Cargo.toml','w').write('[package]\nversion = "1.0.1"\n')
 PY
   git add .
-  git -c user.name=Wes -c user.email=wesbillman@users.noreply.github.com commit -q -s -m 'chore(release): release Buzz Desktop version 1.0.1' -m 'Co-authored-by: Test Automation <test@example.com>'
+  git commit -q -s -m 'chore(release): release Buzz Desktop version 1.0.1' -m 'Co-authored-by: Test Automation <test@example.com>'
   PATH="$mock_bin:$PATH" scripts/desktop_release.py validate --version 1.0.1 --repo block/buzz
+  good_candidate=$(git rev-parse HEAD)
+
+  # A candidate whose Signed-off-by does not match its author is a dishonest
+  # DCO sign-off and must be rejected. Rewrite the author while keeping the
+  # original trailer body, then restore the honest candidate.
+  git -c user.name=Impostor -c user.email=impostor@example.com commit -q --amend --no-edit --reset-author
+  if PATH="$mock_bin:$PATH" scripts/desktop_release.py validate --version 1.0.1 --repo block/buzz >/dev/null 2>&1; then
+    echo "validator accepted a candidate whose sign-off does not match its author" >&2; exit 1
+  fi
+  git reset -q --hard "$good_candidate"
+
+  # The trailer must be a complete anchored line, not substring-matched. A prose
+  # line that merely contains the sign-off text, or a real trailer with trailing
+  # garbage, must be rejected. Both were accepted before the anchored parse.
+  for bogus in \
+    'not-a-trailer Signed-off-by: test <test@example.com>' \
+    'Signed-off-by: test <test@example.com> trailing-garbage'; do
+    git commit -q --amend -m 'chore(release): release Buzz Desktop version 1.0.1' \
+      -m 'Co-authored-by: Test Automation <test@example.com>' -m "$bogus"
+    if PATH="$mock_bin:$PATH" scripts/desktop_release.py validate --version 1.0.1 --repo block/buzz >/dev/null 2>&1; then
+      echo "validator accepted a malformed sign-off: $bogus" >&2; exit 1
+    fi
+    git reset -q --hard "$good_candidate"
+  done
+
+  # Two matching sign-offs are also invalid: the contract is exactly one.
+  git commit -q --amend -m 'chore(release): release Buzz Desktop version 1.0.1' \
+    -m 'Co-authored-by: Test Automation <test@example.com>' \
+    -m 'Signed-off-by: test <test@example.com>' -m 'Signed-off-by: test <test@example.com>'
+  if PATH="$mock_bin:$PATH" scripts/desktop_release.py validate --version 1.0.1 --repo block/buzz >/dev/null 2>&1; then
+    echo "validator accepted duplicate Signed-off-by trailers" >&2; exit 1
+  fi
+  git reset -q --hard "$good_candidate"
+
   grep -Fq "$unrelated_before" CHANGELOG.md
   grep -Fq "$unrelated_after" CHANGELOG.md
   ! grep -Fq "$prior_merge" CHANGELOG.md