diff --git a/.github/workflows/pr.yml b/.github/workflows/pr.yml
index c9b174e9dc3..b04a8a86408 100644
--- a/.github/workflows/pr.yml
+++ b/.github/workflows/pr.yml
@@ -391,9 +391,22 @@ jobs:
 
   verify:
     # Preserve the legacy required-check name while the underlying work runs in parallel.
+    # BLO-20869: verify_serialized_server is folded in here (rather than made
+    # required on its own) so a cancelled/skipped/never-scheduled serialized
+    # shard fails this required check instead of being invisible to the merge
+    # gate. See the issue for the measured latency tradeoff of putting a
+    # ~90-minute job on the required path this way.
     name: verify
     if: ${{ always() }}
-    needs: [helm_chart, typecheck_release_registry, general_tests, worktree_install, build]
+    needs:
+      [
+        helm_chart,
+        typecheck_release_registry,
+        general_tests,
+        worktree_install,
+        build,
+        verify_serialized_server,
+      ]
     runs-on: arc-light
     timeout-minutes: 5
 
@@ -425,6 +438,7 @@ jobs:
           GENERAL_TESTS_RESULT: ${{ needs.general_tests.result }}
           WORKTREE_INSTALL_RESULT: ${{ needs.worktree_install.result }}
           BUILD_RESULT: ${{ needs.build.result }}
+          VERIFY_SERIALIZED_SERVER_RESULT: ${{ needs.verify_serialized_server.result }}
         run: |
           declare -A lane_results=(
             [helm_chart]="$HELM_CHART_RESULT"
@@ -432,6 +446,7 @@ jobs:
             [general_tests]="$GENERAL_TESTS_RESULT"
             [worktree_install]="$WORKTREE_INSTALL_RESULT"
             [build]="$BUILD_RESULT"
+            [verify_serialized_server]="$VERIFY_SERIALIZED_SERVER_RESULT"
           )
 
           cancelled_lanes=()
diff --git a/scripts/__tests__/pr-verify-lane-outcome.test.mjs b/scripts/__tests__/pr-verify-lane-outcome.test.mjs
index 1cfd5eef58e..5581229fdc8 100644
--- a/scripts/__tests__/pr-verify-lane-outcome.test.mjs
+++ b/scripts/__tests__/pr-verify-lane-outcome.test.mjs
@@ -54,6 +54,7 @@ function runVerifyStep(results) {
     GENERAL_TESTS_RESULT: results.general_tests ?? "success",
     WORKTREE_INSTALL_RESULT: results.worktree_install ?? "success",
     BUILD_RESULT: results.build ?? "success",
+    VERIFY_SERIALIZED_SERVER_RESULT: results.verify_serialized_server ?? "success",
   };
   return spawnSync("bash", ["-c", script], { env, encoding: "utf8" });
 }
@@ -104,6 +105,31 @@ test("verify step annotates both a real failure and a cancellation when a run ha
   assert.match(result.stdout, /general_tests/);
 });
 
+// BLO-20869: verify_serialized_server must be treated exactly like the other
+// required lanes -- cancelled, skipped, or never-scheduled (which also reads
+// as "skipped" via `needs`) must all fail this required check instead of
+// being invisible to the merge gate.
+test("verify step fails when the serialized server suite is cancelled", () => {
+  const result = runVerifyStep({ verify_serialized_server: "cancelled" });
+  assert.notEqual(result.status, 0);
+  assert.match(result.stdout, /::error title=verify: lane cancelled::/);
+  assert.match(result.stdout, /verify_serialized_server/);
+});
+
+test("verify step fails when the serialized server suite is skipped", () => {
+  const result = runVerifyStep({ verify_serialized_server: "skipped" });
+  assert.notEqual(result.status, 0);
+  assert.match(result.stdout, /::error title=verify: lane skipped::/);
+  assert.match(result.stdout, /verify_serialized_server/);
+});
+
+test("verify step fails when the serialized server suite genuinely fails", () => {
+  const result = runVerifyStep({ verify_serialized_server: "failure" });
+  assert.notEqual(result.status, 0);
+  assert.match(result.stdout, /::error title=verify: lane failure::/);
+  assert.match(result.stdout, /verify_serialized_server/);
+});
+
 test("verify step annotates a skipped lane as an unmet dependency, not a failure", () => {
   const result = runVerifyStep({ worktree_install: "skipped" });
   assert.notEqual(result.status, 0);