diff --git a/src/shared/bundled-notify-ownership.test.ts b/src/shared/bundled-notify-ownership.test.ts
index 0881e5802..48af2fa5d 100644
--- a/src/shared/bundled-notify-ownership.test.ts
+++ b/src/shared/bundled-notify-ownership.test.ts
@@ -96,6 +96,32 @@ describe("ensureBundledNotifyOwnership", () => {
     expect(readConfig(userConfigPath).plugin).toEqual(["oh-my-openagent", canonicalEntry])
   })
 
+  test("rewrites recognized external notify with underscore dist-tag to bundled owner", () => {
+    // given
+    const userConfigPath = join(userConfigDir, "opencode.json")
+    writeFileSync(userConfigPath, JSON.stringify({ plugin: ["kdco/notify@release_candidate", "oh-my-openagent"] }, null, 2) + "\n")
+
+    // when
+    const result = ensureBundledNotifyOwnership({ projectDirectory: projectDir, packageRoot })
+
+    // then
+    expect(result.changedUserConfig).toBe(true)
+    expect(readConfig(userConfigPath).plugin).toEqual(["oh-my-openagent", canonicalEntry])
+  })
+
+  test("rewrites npm-prefixed recognized notify with underscore dist-tag to bundled owner", () => {
+    // given
+    const userConfigPath = join(userConfigDir, "opencode.json")
+    writeFileSync(userConfigPath, JSON.stringify({ plugin: ["npm:kdco/notify@release_candidate", "oh-my-openagent"] }, null, 2) + "\n")
+
+    // when
+    const result = ensureBundledNotifyOwnership({ projectDirectory: projectDir, packageRoot })
+
+    // then
+    expect(result.changedUserConfig).toBe(true)
+    expect(readConfig(userConfigPath).plugin).toEqual(["oh-my-openagent", canonicalEntry])
+  })
+
   test("rewrites recognized tuple notify in user config when tuple options are empty", () => {
     // given
     const userConfigPath = join(userConfigDir, "opencode.json")
diff --git a/src/shared/bundled-notify-ownership.ts b/src/shared/bundled-notify-ownership.ts
index d77456333..457685685 100644
--- a/src/shared/bundled-notify-ownership.ts
+++ b/src/shared/bundled-notify-ownership.ts
@@ -76,7 +76,7 @@ function isRecognizedExternalNotifyId(entry: string): boolean {
     if (versionSuffix.includes("/")) return false
     if (versionSuffix.includes("\\")) return false
 
-    return /^[a-z0-9.*+!~^<>=| -]+$/i.test(versionSuffix)
+    return /^[a-z0-9_.*+!~^<>=| -]+$/i.test(versionSuffix)
   })
 }