diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 137751b175086..ceed59f794642 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -3592,6 +3592,9 @@ package android.content.pm {
     field public static final int LOCATION_DATA_APP = 0; // 0x0
     field public static final int LOCATION_MEDIA_DATA = 2; // 0x2
     field public static final int LOCATION_MEDIA_OBB = 1; // 0x1
+    field public static final int REASON_CONFIRM_PACKAGE_CHANGE = 0; // 0x0
+    field public static final int REASON_OWNERSHIP_CHANGED = 1; // 0x1
+    field public static final int REASON_REMIND_OWNERSHIP = 2; // 0x2
   }
 
   public static class PackageInstaller.InstallInfo {
@@ -3621,6 +3624,7 @@ package android.content.pm {
     method public boolean getInstallAsFullApp(boolean);
     method public boolean getInstallAsInstantApp(boolean);
     method public boolean getInstallAsVirtualPreload();
+    method public int getPendingUserActionReason();
     method public boolean getRequestDowngrade();
     method public int getRollbackDataPolicy();
     method @NonNull public java.util.Set<java.lang.String> getWhitelistedRestrictedPermissions();
diff --git a/core/java/android/content/pm/PackageInstaller.java b/core/java/android/content/pm/PackageInstaller.java
index 8f295633e01ab..812b5b3145828 100644
--- a/core/java/android/content/pm/PackageInstaller.java
+++ b/core/java/android/content/pm/PackageInstaller.java
@@ -544,6 +544,46 @@ public class PackageInstaller {
     @Retention(RetentionPolicy.SOURCE)
     @interface PackageSourceType{}
 
+    /**
+     * Indicate the user intervention is required when the installer attempts to commit the session.
+     * This is the default case.
+     *
+     * @hide
+     */
+    @SystemApi
+    public static final int REASON_CONFIRM_PACKAGE_CHANGE = 0;
+
+    /**
+     * Indicate the user intervention is required because the update ownership enforcement is
+     * enabled, and the update owner will change.
+     *
+     * @see PackageInstaller.SessionParams#setRequestUpdateOwnership
+     * @see InstallSourceInfo#getUpdateOwnerPackageName
+     * @hide
+     */
+    @SystemApi
+    public static final int REASON_OWNERSHIP_CHANGED = 1;
+
+    /**
+     * Indicate the user intervention is required because the update ownership enforcement is
+     * enabled, and remind the update owner will retain.
+     *
+     * @see PackageInstaller.SessionParams#setRequestUpdateOwnership
+     * @see InstallSourceInfo#getUpdateOwnerPackageName
+     * @hide
+     */
+    @SystemApi
+    public static final int REASON_REMIND_OWNERSHIP = 2;
+
+    /** @hide */
+    @IntDef(prefix = { "REASON_" }, value = {
+            REASON_CONFIRM_PACKAGE_CHANGE,
+            REASON_OWNERSHIP_CHANGED,
+            REASON_REMIND_OWNERSHIP,
+    })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface UserActionReason {}
+
     /** Default set of checksums - includes all available checksums.
      * @see Session#requestChecksums  */
     private static final int DEFAULT_CHECKSUMS =
@@ -2686,9 +2726,18 @@ public class PackageInstaller {
          *              Android S ({@link android.os.Build.VERSION_CODES#S API 31})</li>
          *          </ul>
          *     </li>
-         *     <li>The installer is the {@link InstallSourceInfo#getInstallingPackageName()
-         *     installer of record} of an existing version of the app (in other words, this install
-         *     session is an app update) or the installer is updating itself.</li>
+         *     <li>The installer is:
+         *         <ul>
+         *             <li>The {@link InstallSourceInfo#getUpdateOwnerPackageName() update owner}
+         *             of an existing version of the app (in other words, this install session is
+         *             an app update) if the update ownership enforcement is enabled.</li>
+         *             <li>The {@link InstallSourceInfo#getInstallingPackageName() installer of
+         *             record} of an existing version of the app (in other words, this install
+         *             session is an app update) if the update ownership enforcement isn't
+         *             enabled.</li>
+         *             <li>Updating itself.</li>
+         *         </ul>
+         *     </li>>
          *     <li>The installer declares the
          *     {@link android.Manifest.permission#UPDATE_PACKAGES_WITHOUT_USER_ACTION
          *     UPDATE_PACKAGES_WITHOUT_USER_ACTION} permission.</li>
@@ -3025,6 +3074,9 @@ public class PackageInstaller {
         /** @hide */
         public boolean keepApplicationEnabledSetting;
 
+        /** @hide */
+        public int pendingUserActionReason;
+
         /** {@hide} */
         @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
         public SessionInfo() {
@@ -3079,6 +3131,7 @@ public class PackageInstaller {
             installerUid = source.readInt();
             packageSource = source.readInt();
             keepApplicationEnabledSetting = source.readBoolean();
+            pendingUserActionReason = source.readInt();
         }
 
         /**
@@ -3633,6 +3686,15 @@ public class PackageInstaller {
             return (installFlags & PackageManager.INSTALL_REQUEST_UPDATE_OWNERSHIP) != 0;
         }
 
+        /**
+         * Return the reason for requiring the user action.
+         * @hide
+         */
+        @SystemApi
+        public @UserActionReason int getPendingUserActionReason() {
+            return pendingUserActionReason;
+        }
+
         @Override
         public int describeContents() {
             return 0;
@@ -3683,6 +3745,7 @@ public class PackageInstaller {
             dest.writeInt(installerUid);
             dest.writeInt(packageSource);
             dest.writeBoolean(keepApplicationEnabledSetting);
+            dest.writeInt(pendingUserActionReason);
         }
 
         public static final Parcelable.Creator<SessionInfo>
diff --git a/packages/PackageInstaller/res/values/strings.xml b/packages/PackageInstaller/res/values/strings.xml
index b713c1420928b..cb2baa974b0c2 100644
--- a/packages/PackageInstaller/res/values/strings.xml
+++ b/packages/PackageInstaller/res/values/strings.xml
@@ -37,6 +37,11 @@
     <string name="install_confirm_question">Do you want to install this app?</string>
     <!-- Message for updating an existing app [CHAR LIMIT=NONE] -->
     <string name="install_confirm_question_update">Do you want to update this app?</string>
+    <!-- TODO(b/244413073) Revise the description after getting UX input and UXR on this. -->
+    <!-- Message for updating an existing app when updating owner changed [CHAR LIMIT=NONE] -->
+    <string name="install_confirm_question_update_owner_changed">Updates to this app are currently managed by <xliff:g id="existing_update_owner">%1$s</xliff:g>.\n\nBy updating, you\'ll get future updates from <xliff:g id="new_update_owner">%2$s</xliff:g> instead.</string>
+    <!-- Message for updating an existing app with update owner reminder [CHAR LIMIT=NONE] -->
+    <string name="install_confirm_question_update_owner_reminder">Updates to this app are currently managed by <xliff:g id="existing_update_owner">%1$s</xliff:g>.\n\nDo you want to install this update from <xliff:g id="new_update_owner">%2$s</xliff:g>.</string>
     <!-- [CHAR LIMIT=100] -->
     <string name="install_failed">App not installed.</string>
     <!-- Reason displayed when installation fails because the package was blocked
diff --git a/packages/PackageInstaller/src/com/android/packageinstaller/PackageInstallerActivity.java b/packages/PackageInstaller/src/com/android/packageinstaller/PackageInstallerActivity.java
index 313815839f531..49c9188a2cab8 100644
--- a/packages/PackageInstaller/src/com/android/packageinstaller/PackageInstallerActivity.java
+++ b/packages/PackageInstaller/src/com/android/packageinstaller/PackageInstallerActivity.java
@@ -33,10 +33,12 @@ import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.pm.ApplicationInfo;
+import android.content.pm.InstallSourceInfo;
 import android.content.pm.PackageInfo;
 import android.content.pm.PackageInstaller;
 import android.content.pm.PackageInstaller.SessionInfo;
 import android.content.pm.PackageManager;
+import android.content.pm.PackageManager.ApplicationInfoFlags;
 import android.content.pm.PackageManager.NameNotFoundException;
 import android.graphics.drawable.BitmapDrawable;
 import android.net.Uri;
@@ -47,9 +49,11 @@ import android.os.Process;
 import android.os.UserHandle;
 import android.os.UserManager;
 import android.provider.Settings;
+import android.text.TextUtils;
 import android.util.Log;
 import android.view.View;
 import android.widget.Button;
+import android.widget.TextView;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
@@ -88,6 +92,7 @@ public class PackageInstallerActivity extends AlertActivity {
     private int mOriginatingUid = Process.INVALID_UID;
     private String mOriginatingPackage; // The package name corresponding to #mOriginatingUid
     private int mActivityResultCode = Activity.RESULT_CANCELED;
+    private int mPendingUserActionReason = -1;
 
     private final boolean mLocalLOGV = false;
     PackageManager mPm;
@@ -132,10 +137,27 @@ public class PackageInstallerActivity extends AlertActivity {
     private boolean mEnableOk = false;
 
     private void startInstallConfirm() {
-        View viewToEnable;
+        TextView viewToEnable;
 
         if (mAppInfo != null) {
             viewToEnable = requireViewById(R.id.install_confirm_question_update);
+
+            final CharSequence existingUpdateOwnerLabel = getExistingUpdateOwnerLabel();
+            final CharSequence requestedUpdateOwnerLabel = getApplicationLabel(mCallingPackage);
+            if (!TextUtils.isEmpty(existingUpdateOwnerLabel)) {
+                if (mPendingUserActionReason == PackageInstaller.REASON_OWNERSHIP_CHANGED) {
+                    viewToEnable.setText(
+                            getString(R.string.install_confirm_question_update_owner_changed,
+                                    existingUpdateOwnerLabel, requestedUpdateOwnerLabel));
+                } else if (mPendingUserActionReason == PackageInstaller.REASON_REMIND_OWNERSHIP
+                        || mPendingUserActionReason
+                        == PackageInstaller.REASON_CONFIRM_PACKAGE_CHANGE) {
+                    viewToEnable.setText(
+                            getString(R.string.install_confirm_question_update_owner_reminder,
+                                    existingUpdateOwnerLabel, requestedUpdateOwnerLabel));
+                }
+            }
+
             mOk.setText(R.string.update);
         } else {
             // This is a new application with no permissions.
@@ -149,6 +171,27 @@ public class PackageInstallerActivity extends AlertActivity {
         mOk.setFilterTouchesWhenObscured(true);
     }
 
+    private CharSequence getExistingUpdateOwnerLabel() {
+        try {
+            final String packageName = mPkgInfo.packageName;
+            final InstallSourceInfo sourceInfo = mPm.getInstallSourceInfo(packageName);
+            final String existingUpdateOwner = sourceInfo.getUpdateOwnerPackageName();
+            return getApplicationLabel(existingUpdateOwner);
+        } catch (NameNotFoundException e) {
+            return null;
+        }
+    }
+
+    private CharSequence getApplicationLabel(String packageName) {
+        try {
+            final ApplicationInfo appInfo = mPm.getApplicationInfo(packageName,
+                    ApplicationInfoFlags.of(0));
+            return mPm.getApplicationLabel(appInfo);
+        } catch (NameNotFoundException e) {
+            return null;
+        }
+    }
+
     /**
      * Replace any dialog shown by the dialog with the one for the given {@link #createDialog(int)}.
      *
@@ -344,6 +387,7 @@ public class PackageInstallerActivity extends AlertActivity {
             packageSource = Uri.fromFile(new File(resolvedBaseCodePath));
             mOriginatingURI = null;
             mReferrerURI = null;
+            mPendingUserActionReason = info.getPendingUserActionReason();
         } else if (PackageInstaller.ACTION_CONFIRM_PRE_APPROVAL.equals(action)) {
             final int sessionId = intent.getIntExtra(PackageInstaller.EXTRA_SESSION_ID,
                     -1 /* defaultValue */);
@@ -358,11 +402,13 @@ public class PackageInstallerActivity extends AlertActivity {
             packageSource = info;
             mOriginatingURI = null;
             mReferrerURI = null;
+            mPendingUserActionReason = info.getPendingUserActionReason();
         } else {
             mSessionId = -1;
             packageSource = intent.getData();
             mOriginatingURI = intent.getParcelableExtra(Intent.EXTRA_ORIGINATING_URI);
             mReferrerURI = intent.getParcelableExtra(Intent.EXTRA_REFERRER);
+            mPendingUserActionReason = PackageInstaller.REASON_CONFIRM_PACKAGE_CHANGE;
         }
 
         // if there's nothing to do, quietly slip into the ether
diff --git a/services/core/java/com/android/server/pm/PackageInstallerSession.java b/services/core/java/com/android/server/pm/PackageInstallerSession.java
index 4bbf09de72a00..8ea77889acc79 100644
--- a/services/core/java/com/android/server/pm/PackageInstallerSession.java
+++ b/services/core/java/com/android/server/pm/PackageInstallerSession.java
@@ -89,6 +89,7 @@ import android.content.pm.PackageInstaller;
 import android.content.pm.PackageInstaller.PreapprovalDetails;
 import android.content.pm.PackageInstaller.SessionInfo;
 import android.content.pm.PackageInstaller.SessionParams;
+import android.content.pm.PackageInstaller.UserActionReason;
 import android.content.pm.PackageManager;
 import android.content.pm.PackageManager.PackageInfoFlags;
 import android.content.pm.PackageManagerInternal;
@@ -447,6 +448,9 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
     @GuardedBy("mLock")
     private boolean mHasDeviceAdminReceiver;
 
+    @GuardedBy("mLock")
+    private int mUserActionRequirement;
+
     static class FileEntry {
         private final int mIndex;
         private final InstallationFile mFile;
@@ -843,10 +847,17 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
     private static final int USER_ACTION_NOT_NEEDED = 0;
     private static final int USER_ACTION_REQUIRED = 1;
     private static final int USER_ACTION_PENDING_APK_PARSING = 2;
+    private static final int USER_ACTION_REQUIRED_UPDATE_OWNER_CHANGED = 3;
+    private static final int USER_ACTION_REQUIRED_UPDATE_OWNER_RETAINED = 4;
 
-    @IntDef({USER_ACTION_NOT_NEEDED, USER_ACTION_REQUIRED, USER_ACTION_PENDING_APK_PARSING})
-    @interface
-    UserActionRequirement {}
+    @IntDef({
+            USER_ACTION_NOT_NEEDED,
+            USER_ACTION_REQUIRED,
+            USER_ACTION_PENDING_APK_PARSING,
+            USER_ACTION_REQUIRED_UPDATE_OWNER_CHANGED,
+            USER_ACTION_REQUIRED_UPDATE_OWNER_RETAINED
+    })
+    @interface UserActionRequirement {}
 
     /**
      * Checks if the permissions still need to be confirmed.
@@ -900,8 +911,13 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
         final String existingInstallerPackageName = existingInstallSourceInfo != null
                 ? existingInstallSourceInfo.getInstallingPackageName()
                 : null;
+        final String existingUpdateOwnerPackageName = existingInstallSourceInfo != null
+                ? existingInstallSourceInfo.getUpdateOwnerPackageName()
+                : null;
         final boolean isInstallerOfRecord = isUpdate
                 && Objects.equals(existingInstallerPackageName, getInstallerPackageName());
+        final boolean isUpdateOwner = Objects.equals(existingUpdateOwnerPackageName,
+                getInstallerPackageName());
         final boolean isSelfUpdate = targetPackageUid == mInstallerUid;
         final boolean isPermissionGranted = isInstallPermissionGranted
                 || (isUpdatePermissionGranted && isUpdate)
@@ -909,16 +925,35 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
                 || (isInstallDpcPackagesPermissionGranted && hasDeviceAdminReceiver);
         final boolean isInstallerRoot = (mInstallerUid == Process.ROOT_UID);
         final boolean isInstallerSystem = (mInstallerUid == Process.SYSTEM_UID);
+        final boolean isInstallerShell = (mInstallerUid == Process.SHELL_UID);
+        final boolean isUpdateOwnershipEnforcementEnabled =
+                mPm.isUpdateOwnershipEnforcementAvailable()
+                        && existingUpdateOwnerPackageName != null;
 
-        // Device owners and affiliated profile owners  are allowed to silently install packages, so
+        // Device owners and affiliated profile owners are allowed to silently install packages, so
         // the permission check is waived if the installer is the device owner.
-        final boolean noUserActionNecessary = isPermissionGranted || isInstallerRoot
-                || isInstallerSystem || isInstallerDeviceOwnerOrAffiliatedProfileOwner();
+        final boolean noUserActionNecessary = isInstallerRoot || isInstallerSystem
+                || isInstallerDeviceOwnerOrAffiliatedProfileOwner();
 
         if (noUserActionNecessary) {
             return USER_ACTION_NOT_NEEDED;
         }
 
+        if (isUpdateOwnershipEnforcementEnabled
+                && !isApexSession()
+                && !isUpdateOwner
+                && !isInstallerShell) {
+            final boolean isRequestUpdateOwner =
+                    (params.installFlags & PackageManager.INSTALL_REQUEST_UPDATE_OWNERSHIP) != 0;
+
+            return isRequestUpdateOwner ? USER_ACTION_REQUIRED_UPDATE_OWNER_CHANGED
+                    : USER_ACTION_REQUIRED_UPDATE_OWNER_RETAINED;
+        }
+
+        if (isPermissionGranted) {
+            return USER_ACTION_NOT_NEEDED;
+        }
+
         if (snapshot.isInstallDisabledForPackage(getInstallerPackageName(), mInstallerUid,
                 userId)) {
             // show the installer to account for device policy or unknown sources use cases
@@ -927,13 +962,20 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
 
         if (params.requireUserAction == SessionParams.USER_ACTION_NOT_REQUIRED
                 && isUpdateWithoutUserActionPermissionGranted
-                && (isInstallerOfRecord || isSelfUpdate)) {
+                && ((isUpdateOwnershipEnforcementEnabled ? isUpdateOwner
+                : isInstallerOfRecord) || isSelfUpdate)) {
             return USER_ACTION_PENDING_APK_PARSING;
         }
 
         return USER_ACTION_REQUIRED;
     }
 
+    private void updateUserActionRequirement(int requirement) {
+        synchronized (mLock) {
+            mUserActionRequirement = requirement;
+        }
+    }
+
     @SuppressWarnings("GuardedBy" /*mPm.mInstaller is {@code final} field*/)
     public PackageInstallerSession(PackageInstallerService.InternalCallback callback,
             Context context, PackageManagerService pm,
@@ -1122,6 +1164,7 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
             info.installerUid = mInstallerUid;
             info.packageSource = params.packageSource;
             info.keepApplicationEnabledSetting = params.keepApplicationEnabledSetting;
+            info.pendingUserActionReason = userActionRequirementToReason(mUserActionRequirement);
         }
         return info;
     }
@@ -2222,7 +2265,10 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
         @UserActionRequirement int userActionRequirement = USER_ACTION_NOT_NEEDED;
         // TODO(b/159331446): Move this to makeSessionActiveForInstall and update javadoc
         userActionRequirement = session.computeUserActionRequirement();
-        if (userActionRequirement == USER_ACTION_REQUIRED) {
+        session.updateUserActionRequirement(userActionRequirement);
+        if (userActionRequirement == USER_ACTION_REQUIRED
+                || userActionRequirement == USER_ACTION_REQUIRED_UPDATE_OWNER_CHANGED
+                || userActionRequirement == USER_ACTION_REQUIRED_UPDATE_OWNER_RETAINED) {
             session.sendPendingUserActionIntent(target);
             return true;
         }
@@ -2255,6 +2301,18 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
         return false;
     }
 
+    private static @UserActionReason int userActionRequirementToReason(
+            @UserActionRequirement int requirement) {
+        switch (requirement) {
+            case USER_ACTION_REQUIRED_UPDATE_OWNER_CHANGED:
+                return PackageInstaller.REASON_OWNERSHIP_CHANGED;
+            case USER_ACTION_REQUIRED_UPDATE_OWNER_RETAINED:
+                return PackageInstaller.REASON_REMIND_OWNERSHIP;
+            default:
+                return PackageInstaller.REASON_CONFIRM_PACKAGE_CHANGE;
+        }
+    }
+
     /**
      * Find out any session needs user action.
      *