diff --git a/scripts/github/barnacle-auto-response.mjs b/scripts/github/barnacle-auto-response.mjs
index d36fdf249ec..d132b114a23 100644
--- a/scripts/github/barnacle-auto-response.mjs
+++ b/scripts/github/barnacle-auto-response.mjs
@@ -833,6 +833,15 @@ function shouldRemoveProofSufficientLabel(
   return true;
 }
 
+const negativeProofLabels = new Set([NEEDS_REAL_BEHAVIOR_PROOF_LABEL, MOCK_ONLY_PROOF_LABEL]);
+
+function shouldPreserveClawSweeperProofJudgment(context, labelSet) {
+  return (
+    labelSet.has(PROOF_SUFFICIENT_LABEL) &&
+    !["edited", "synchronize"].includes(context.payload.action)
+  );
+}
+
 async function applyPullRequestCandidateLabels(github, context, core, pullRequest, labelSet) {
   const files = await listPullRequestFiles(github, context, pullRequest);
   const hasExactHeadClawSweeperProof =
@@ -854,8 +863,11 @@ async function applyPullRequestCandidateLabels(github, context, core, pullReques
     },
     files,
   );
+  const candidateLabelsToApply = shouldPreserveClawSweeperProofJudgment(context, labelSet)
+    ? classifiedLabels.filter((label) => !negativeProofLabels.has(label))
+    : classifiedLabels;
   const staleProofLabels = structuralProofLabelValues.filter(
-    (label) => labelSet.has(label) && !classifiedLabels.includes(label),
+    (label) => labelSet.has(label) && !candidateLabelsToApply.includes(label),
   );
   if (
     labelSet.has(PROOF_SUFFICIENT_LABEL) &&
@@ -870,7 +882,14 @@ async function applyPullRequestCandidateLabels(github, context, core, pullReques
     staleProofLabels.push(PROOF_SUFFICIENT_LABEL);
   }
   await removeLabels(github, context, pullRequest.number, staleProofLabels, labelSet);
-  await addMissingLabels(github, context, core, pullRequest.number, classifiedLabels, labelSet);
+  await addMissingLabels(
+    github,
+    context,
+    core,
+    pullRequest.number,
+    candidateLabelsToApply,
+    labelSet,
+  );
 }
 
 function isAutomationUser(user, fallbackLogin = "") {
diff --git a/test/scripts/barnacle-auto-response.test.ts b/test/scripts/barnacle-auto-response.test.ts
index 8d1976ebbba..6634a134beb 100644
--- a/test/scripts/barnacle-auto-response.test.ts
+++ b/test/scripts/barnacle-auto-response.test.ts
@@ -1011,6 +1011,57 @@ describe("barnacle-auto-response", () => {
     });
 
     expect(calls.removeLabel).toEqual([]);
+    expect(calls.addLabels.flatMap((call) => call.labels)).not.toContain(
+      candidateLabels.needsRealBehaviorProof,
+    );
+  });
+
+  it("does not re-add negative proof labels while sufficient proof is present", async () => {
+    const { calls, github } = barnacleGithub([file("src/gateway/server.ts")]);
+
+    await runBarnacleAutoResponse({
+      github,
+      context: barnacleContext({}, [PROOF_SUFFICIENT_LABEL], {
+        action: "unlabeled",
+        label: { name: candidateLabels.needsRealBehaviorProof },
+        sender: { login: "maintainer", type: "User" },
+      }),
+      core: {
+        info: () => undefined,
+      },
+    });
+
+    expect(calls.removeLabel).toEqual([]);
+    expect(calls.addLabels.flatMap((call) => call.labels)).not.toContain(
+      candidateLabels.needsRealBehaviorProof,
+    );
+  });
+
+  it("removes negative proof labels when sufficient proof is already present", async () => {
+    const { calls, github } = barnacleGithub([file("src/gateway/server.ts")]);
+
+    await runBarnacleAutoResponse({
+      github,
+      context: barnacleContext(
+        {},
+        [PROOF_SUFFICIENT_LABEL, candidateLabels.needsRealBehaviorProof],
+        {
+          action: "labeled",
+          label: { name: "status: ready for maintainer look" },
+          sender: { login: "openclaw-clawsweeper[bot]", type: "Bot" },
+        },
+      ),
+      core: {
+        info: () => undefined,
+      },
+    });
+
+    expect(calls.removeLabel).toEqual([
+      expectedRemoveLabel(123, candidateLabels.needsRealBehaviorProof),
+    ]);
+    expect(calls.addLabels.flatMap((call) => call.labels)).not.toContain(
+      candidateLabels.needsRealBehaviorProof,
+    );
   });
 
   it("does not let Barnacle veto ClawSweeper's sufficient proof label add", async () => {