diff --git a/src/plugins/bundled-runtime-deps.test.ts b/src/plugins/bundled-runtime-deps.test.ts
index c269d3fd79d..e7fc0309019 100644
--- a/src/plugins/bundled-runtime-deps.test.ts
+++ b/src/plugins/bundled-runtime-deps.test.ts
@@ -2126,6 +2126,51 @@ describe("ensureBundledPluginRuntimeDeps", () => {
     ).toBe(true);
   });
 
+  it("treats a PID-alive lock with matching pidStartTimeMs as held by the same incarnation", () => {
+    expect(
+      bundledRuntimeDepsTesting.shouldRemoveRuntimeDepsLock(
+        { pid: 7, pidStartTimeMs: 1_000, createdAtMs: 2_000 },
+        2_500,
+        () => true,
+        // Live PID's start-time matches owner.pidStartTimeMs → same process
+        () => 1_000,
+      ),
+    ).toBe(false);
+  });
+
+  it("expires a PID-alive lock when the live PID's start-time differs (Docker PID reuse)", () => {
+    // Models the failure mode that motivated this change: inside a container
+    // the gateway is always PID 1 (or PID 7 with `init: true`), so a stale
+    // lock from a previous incarnation looks "alive" if we only consult
+    // isProcessAlive. Capturing the writer's start-time and comparing it to
+    // the live PID's start-time disambiguates incarnations.
+    expect(
+      bundledRuntimeDepsTesting.shouldRemoveRuntimeDepsLock(
+        { pid: 7, pidStartTimeMs: 1_000, createdAtMs: 2_000 },
+        2_500,
+        () => true,
+        // Same PID, but a different incarnation started later → stale.
+        () => 9_000,
+      ),
+    ).toBe(true);
+  });
+
+  it("treats a PID-alive lock as fresh when start-time evidence cannot be read", () => {
+    // Defensive: when readProcessStartTimeMs returns null (legacy lock with
+    // no pidStartTimeMs, or a platform that does not expose it) we keep the
+    // pre-existing behavior of trusting isAlive(pid). The only verified
+    // disambiguation path is start-time evidence on both sides; without it
+    // we err toward "still held" rather than risk stomping a real install.
+    expect(
+      bundledRuntimeDepsTesting.shouldRemoveRuntimeDepsLock(
+        { pid: 7, pidStartTimeMs: 1_000, createdAtMs: 0 },
+        Number.MAX_SAFE_INTEGER,
+        () => true,
+        () => null,
+      ),
+    ).toBe(false);
+  });
+
   it("does not expire fresh ownerless runtime-deps install locks", () => {
     expect(
       bundledRuntimeDepsTesting.shouldRemoveRuntimeDepsLock(
diff --git a/src/plugins/bundled-runtime-deps.ts b/src/plugins/bundled-runtime-deps.ts
index 6a6c68b986e..e6e1cb76566 100644
--- a/src/plugins/bundled-runtime-deps.ts
+++ b/src/plugins/bundled-runtime-deps.ts
@@ -456,8 +456,65 @@ function isProcessAlive(pid: number): boolean {
   }
 }
 
+// Approximate epoch-ms when the current process started, captured once per
+// Node lifetime so the lock owner record carries a value that is stable
+// across `Date.now()` clock skew within the running process.
+const CURRENT_PROCESS_START_TIME_MS = Math.round(Date.now() - process.uptime() * 1000);
+
+// Approximate epoch-ms when `pid` started running, or null when the platform
+// or runtime cannot determine it. Used to distinguish two different process
+// incarnations that happen to share the same numeric PID — most notably
+// inside Docker containers, where the gateway is always PID 1 (or PID 7
+// with `init: true`) in its container PID namespace, so a stale lock left
+// by a previous incarnation looks live to the new one if we only consult
+// `isAlive(pid)`.
+function readProcessStartTimeMs(pid: number): number | null {
+  if (!Number.isInteger(pid) || pid <= 0) {
+    return null;
+  }
+  if (process.platform !== "linux") {
+    return null;
+  }
+  let stat: string;
+  try {
+    stat = fs.readFileSync(`/proc/${pid}/stat`, "utf8");
+  } catch {
+    return null;
+  }
+  // /proc/<pid>/stat: PID (comm) state ppid pgrp ... starttime ... where
+  // `comm` may contain spaces and parens, so we anchor on the LAST `)` and
+  // count whitespace-separated fields after it. Field index 22 (1-based) is
+  // starttime, expressed in clock ticks since boot. After the `)` the next
+  // field is `state` (1), then ppid (2), pgrp (3), session (4), tty_nr (5),
+  // tpgid (6), flags (7), minflt (8), cminflt (9), majflt (10), cmajflt
+  // (11), utime (12), stime (13), cutime (14), cstime (15), priority (16),
+  // nice (17), num_threads (18), itrealvalue (19), starttime (20).
+  const lastParen = stat.lastIndexOf(")");
+  if (lastParen === -1) {
+    return null;
+  }
+  const tail = stat
+    .slice(lastParen + 1)
+    .trim()
+    .split(/\s+/);
+  // tail[0] is `state`; starttime is therefore tail[19].
+  const starttimeJiffies = Number(tail[19]);
+  if (!Number.isFinite(starttimeJiffies)) {
+    return null;
+  }
+  // sysconf(_SC_CLK_TCK) is universally 100 on Linux x86/arm targets. We
+  // hard-code that here rather than spawning getconf — the exact tick rate
+  // does not matter for our purposes as long as it is stable: the starttime
+  // we capture for our own process and the starttime we read for the
+  // lock-owner PID are converted with the same constant, so equality holds.
+  const clockTicksPerSecond = 100;
+  const bootTimeMs = Date.now() - os.uptime() * 1000;
+  return Math.round(bootTimeMs + (starttimeJiffies * 1000) / clockTicksPerSecond);
+}
+
 type RuntimeDepsLockOwner = {
   pid?: number;
+  pidStartTimeMs?: number;
   createdAtMs?: number;
   ownerFileState: "ok" | "missing" | "invalid";
   ownerFilePath: string;
@@ -501,6 +558,7 @@ function readRuntimeDepsLockOwner(lockDir: string): RuntimeDepsLockOwner {
   }
   return {
     pid: typeof owner?.pid === "number" ? owner.pid : undefined,
+    pidStartTimeMs: typeof owner?.pidStartTimeMs === "number" ? owner.pidStartTimeMs : undefined,
     createdAtMs: typeof owner?.createdAtMs === "number" ? owner.createdAtMs : undefined,
     ownerFileState,
     ownerFilePath,
@@ -524,12 +582,32 @@ function latestFiniteMs(values: readonly (number | undefined)[]): number | undef
 }
 
 function shouldRemoveRuntimeDepsLock(
-  owner: Pick<RuntimeDepsLockOwner, "pid" | "createdAtMs" | "lockDirMtimeMs" | "ownerFileMtimeMs">,
+  owner: Pick<
+    RuntimeDepsLockOwner,
+    "pid" | "pidStartTimeMs" | "createdAtMs" | "lockDirMtimeMs" | "ownerFileMtimeMs"
+  >,
   nowMs: number,
   isAlive: (pid: number) => boolean = isProcessAlive,
+  readStartTimeMs: (pid: number) => number | null = readProcessStartTimeMs,
 ): boolean {
   if (typeof owner.pid === "number") {
-    return !isAlive(owner.pid);
+    if (!isAlive(owner.pid)) {
+      return true;
+    }
+    // PID is alive — but inside Docker the new process can share the same
+    // PID as the dead writer. If we recorded the writer's start-time and we
+    // can read the live PID's start-time, mismatch means a different
+    // incarnation owns this PID now and the lock is stale. When start-time
+    // evidence is unavailable on either side, fall through to the existing
+    // PID-alive-means-fresh behavior so legacy locks keep working as
+    // before.
+    if (typeof owner.pidStartTimeMs === "number") {
+      const liveStartTimeMs = readStartTimeMs(owner.pid);
+      if (liveStartTimeMs !== null && liveStartTimeMs !== owner.pidStartTimeMs) {
+        return true;
+      }
+    }
+    return false;
   }
 
   if (typeof owner.createdAtMs === "number") {
@@ -614,7 +692,15 @@ export function withBundledRuntimeDepsFilesystemLock<T>(
       try {
         fs.writeFileSync(
           path.join(lockDir, BUNDLED_RUNTIME_DEPS_LOCK_OWNER_FILE),
-          `${JSON.stringify({ pid: process.pid, createdAtMs: Date.now() }, null, 2)}\n`,
+          `${JSON.stringify(
+            {
+              pid: process.pid,
+              pidStartTimeMs: CURRENT_PROCESS_START_TIME_MS,
+              createdAtMs: Date.now(),
+            },
+            null,
+            2,
+          )}\n`,
           "utf8",
         );
       } catch (ownerWriteError) {
@@ -2387,7 +2473,15 @@ async function withBundledRuntimeDepsInstallRootLockAsync<T>(
       try {
         fs.writeFileSync(
           path.join(lockDir, BUNDLED_RUNTIME_DEPS_LOCK_OWNER_FILE),
-          `${JSON.stringify({ pid: process.pid, createdAtMs: Date.now() }, null, 2)}\n`,
+          `${JSON.stringify(
+            {
+              pid: process.pid,
+              pidStartTimeMs: CURRENT_PROCESS_START_TIME_MS,
+              createdAtMs: Date.now(),
+            },
+            null,
+            2,
+          )}\n`,
           "utf8",
         );
       } catch (ownerWriteError) {