diff --git a/docs/web-source-location.md b/docs/web-source-location.md
index 743ad3a1f9..881a7056c7 100644
--- a/docs/web-source-location.md
+++ b/docs/web-source-location.md
@@ -95,6 +95,12 @@ heap limit is established. Cleanup may extend the deadline and an unconfirmed
 cleanup overrides success with `cleanup_incomplete` and the owning
 operation/resources.
 
+The decoder releases its owned codec process before removing the private request
+directory. A cleanup failure reports only the owners still pending: the process
+run token while process release is unconfirmed, and the directory until removal
+succeeds. A later successful retry settles every error bound to that command;
+historical failure diagnostics remain available.
+
 Complete evidence is bounded by a 4 MiB map, 32 MiB codec reply, 262144 decoded
 rows/segments and 64 nested section levels. Those structural budgets and the
 192 MiB codec heap have no runtime override. Exceeding a budget returns an explicit
diff --git a/src/javascript/sourceMaps/SourceMapCommand.ts b/src/javascript/sourceMaps/SourceMapCommand.ts
index 476ac23158..3cf7485560 100644
--- a/src/javascript/sourceMaps/SourceMapCommand.ts
+++ b/src/javascript/sourceMaps/SourceMapCommand.ts
@@ -154,6 +154,7 @@ class OwnedCodec implements SourceMapCleanupOwner {
   readonly #runId = `rea-source-map-${randomUUID()}`;
   #runtime: SourceMapCodecRuntime | undefined;
   #supervisor: ProviderProcessSupervisor | undefined;
+  #cleanupAnchor: SourceMapCleanupFailure | undefined;
   #outcome: CodecOutcome | undefined;
   #drainStop: CodecPhysicalObservation | undefined;
   readonly #onInterruption: () => void;
@@ -462,6 +463,14 @@ class OwnedCodec implements SourceMapCleanupOwner {
     );
   }
 
+  /** Current ownership, independent of historical cleanup diagnostics. */
+  get cleanupResources(): readonly string[] {
+    return [
+      ...(this.#supervisor === undefined ? [] : [this.#runId]),
+      ...(this.#runtime === undefined ? [] : [this.#runtime.path]),
+    ];
+  }
+
   async close(
     previousError: string | null,
   ): Promise<ProviderCleanupError | undefined> {
@@ -483,21 +492,20 @@ class OwnedCodec implements SourceMapCleanupOwner {
         failures.push(message(cause));
       }
     }
-    return failures.length === 0
-      ? undefined
-      : new SourceMapCleanupFailure(
-          this,
-          [
-            this.#runId,
-            ...(this.#runtime === undefined ? [] : [this.#runtime.path]),
-          ],
-          {
-            map_path: this.path,
-            cleanup_failures: failures,
-            previous_error: previousError,
-            codec_pid: this.#supervisor?.launch.process.pid ?? null,
-          },
-        );
+    if (failures.length === 0) {
+      this.#cleanupAnchor?.resolveCleanup();
+      this.#cleanupAnchor = undefined;
+      return undefined;
+    }
+    const failure = new SourceMapCleanupFailure(this, this.cleanupResources, {
+      map_path: this.path,
+      cleanup_failures: failures,
+      previous_error: previousError,
+      codec_pid: this.#supervisor?.launch.process.pid ?? null,
+    }).bindCleanupResourceOwner(this);
+    if (this.#cleanupAnchor === undefined) this.#cleanupAnchor = failure;
+    else failure.bindCleanupDependencies([this.#cleanupAnchor], this);
+    return failure;
   }
 }
 const message = (cause: unknown): string =>
diff --git a/src/javascript/sourceMaps/SourceMapDecoder.test.ts b/src/javascript/sourceMaps/SourceMapDecoder.test.ts
index c350edf3dd..dc062ac01b 100644
--- a/src/javascript/sourceMaps/SourceMapDecoder.test.ts
+++ b/src/javascript/sourceMaps/SourceMapDecoder.test.ts
@@ -2,12 +2,14 @@ import { access } from "node:fs/promises";
 import { expect, it } from "vitest";
 import { SourceMapDecoder } from "./SourceMapDecoder.js";
 import { AnalysisCancelledError } from "../../domain/analysisErrorCore.js";
+import { projectAnalysisError } from "../../domain/analysisErrorProjection.js";
 import {
   SourceMapCleanupFailure,
   type SourceMapDecoderDependencies,
 } from "./SourceMapCommand.js";
 import { PrivateRuntimeRoot } from "../../process/PrivateRuntimeRoot.js";
 import { spawnOwnedProviderProcess } from "../../process/ProviderProcess.js";
+import { cleanupOwnedProcessGroup } from "../../process/ProcessOwnership.js";
 import {
   webSourceLocationArgs,
   webSourceLocationFixture,
@@ -69,6 +71,7 @@ it("retains failed cleanup ownership and retries it before another decode", asyn
     if (!(failed.error instanceof SourceMapCleanupFailure))
       throw new Error("expected source-map cleanup ownership");
     expect(failed.error.cleanupOwner).toBeDefined();
+    expect(failed.error.cleanupResources).toEqual([root.path]);
     expect(failed.error.diagnostics).toMatchObject({
       cleanup_failures: ["injected root cleanup failure"],
     });
@@ -87,7 +90,119 @@ it("retains failed cleanup ownership and retries it before another decode", asyn
     expect(retried.error._tag).toBe("AnalysisInputError");
     expect(cleanupAttempts).toBe(2);
     await expect(access(root.path)).rejects.toMatchObject({ code: "ENOENT" });
+    expect(failed.error.cleanupIncomplete).toBe(false);
+    expect(failed.error.cleanupResources).toEqual([]);
+    expect(projectAnalysisError(failed.error).code).not.toBe(
+      "cleanup_incomplete",
+    );
+    expect(failed.error.diagnostics).toMatchObject({
+      cleanup_failures: ["injected root cleanup failure"],
+    });
   } finally {
     await decoder.close();
   }
 });
+
+it("settles every source-map cleanup failure when final close releases the exact runtime", async () => {
+  const root = await PrivateRuntimeRoot.create({
+    prefix: "rea-source-map-final-cleanup-test-",
+  });
+  let attempts = 0;
+  const decoder = new SourceMapDecoder({
+    prepareOwnership: async () => {},
+    createRuntime: async () => ({
+      path: root.path,
+      close: async () => {
+        attempts += 1;
+        if (attempts <= 2)
+          throw new Error(`runtime cleanup attempt ${String(attempts)} failed`);
+        await root.close();
+      },
+    }),
+    launcher: async () => {
+      throw new Error("controlled launch failure");
+    },
+  });
+  try {
+    const initial = await decoder.trace(input);
+    if (initial.ok) throw new Error("expected initial cleanup failure");
+    const retry = await decoder.trace(input);
+    if (retry.ok) throw new Error("expected retry cleanup failure");
+    for (const failure of [initial.error, retry.error]) {
+      expect(failure.cleanupIncomplete).toBe(true);
+      expect(failure.cleanupResources).toEqual([root.path]);
+    }
+    await expect(access(root.path)).resolves.toBeUndefined();
+    await decoder.close();
+    expect(attempts).toBe(3);
+    await expect(access(root.path)).rejects.toMatchObject({ code: "ENOENT" });
+    for (const failure of [initial.error, retry.error]) {
+      expect(failure.cleanupIncomplete).toBe(false);
+      expect(failure.cleanupResources).toEqual([]);
+      expect(projectAnalysisError(failure).code).not.toBe("cleanup_incomplete");
+      expect(failure.diagnostics?.cleanup_failures).toEqual([
+        expect.stringContaining("runtime cleanup attempt"),
+      ]);
+    }
+  } finally {
+    await decoder.close();
+  }
+});
+
+it("attributes cleanup resources to the remaining process and directory owners", async () => {
+  const root = await PrivateRuntimeRoot.create({
+    prefix: "rea-source-map-mixed-cleanup-test-",
+  });
+  let denyProcessRelease = true;
+  let rootAttempts = 0;
+  let runId: string | undefined;
+  const decoder = new SourceMapDecoder({
+    prepareOwnership: async () => {},
+    createRuntime: async () => ({
+      path: root.path,
+      close: async () => {
+        rootAttempts += 1;
+        if (rootAttempts === 1)
+          throw new Error("controlled directory cleanup failure");
+        await root.close();
+      },
+    }),
+    launcher: async (options) => {
+      runId = options.runId;
+      const spawned = await spawnOwnedProviderProcess({
+        ...options,
+        arguments: ["-e", "process.exit(0)"],
+      });
+      return {
+        ...spawned,
+        cleanup: async () =>
+          denyProcessRelease
+            ? { cleaned: false, reason: "controlled process cleanup failure" }
+            : spawned.cleanup === undefined
+              ? cleanupOwnedProcessGroup(spawned.ownership)
+              : spawned.cleanup(),
+      };
+    },
+  });
+  try {
+    const initial = await decoder.trace(input);
+    if (initial.ok) throw new Error("expected process cleanup failure");
+    expect(initial.error.cleanupResources).toEqual([runId, root.path]);
+    expect(rootAttempts).toBe(0);
+    denyProcessRelease = false;
+    await expect(decoder.close()).rejects.toMatchObject({
+      cleanupIncomplete: true,
+    });
+    expect(rootAttempts).toBe(1);
+    expect(initial.error.cleanupIncomplete).toBe(true);
+    expect(initial.error.cleanupResources).toEqual([root.path]);
+    await expect(access(root.path)).resolves.toBeUndefined();
+    await decoder.close();
+    expect(initial.error.cleanupIncomplete).toBe(false);
+    expect(initial.error.cleanupResources).toEqual([]);
+    await expect(access(root.path)).rejects.toMatchObject({ code: "ENOENT" });
+  } finally {
+    denyProcessRelease = false;
+    await decoder.close();
+  }
+});