diff --git a/composeApp/src/androidMain/kotlin/com/nuvio/app/MainActivity.kt b/composeApp/src/androidMain/kotlin/com/nuvio/app/MainActivity.kt
index ad83b451..0ce6bee4 100644
--- a/composeApp/src/androidMain/kotlin/com/nuvio/app/MainActivity.kt
+++ b/composeApp/src/androidMain/kotlin/com/nuvio/app/MainActivity.kt
@@ -12,6 +12,7 @@ import androidx.core.splashscreen.SplashScreen.Companion.installSplashScreen
 import com.nuvio.app.core.auth.AuthStorage
 import com.nuvio.app.core.deeplink.handleAppUrl
 import com.nuvio.app.core.storage.PlatformLocalAccountDataCleaner
+import com.nuvio.app.core.sync.SyncClientIdentityStorage
 import com.nuvio.app.features.addons.AddonStorage
 import com.nuvio.app.features.collection.CollectionMobileSettingsStorage
 import com.nuvio.app.features.collection.CollectionStorage
@@ -66,6 +67,7 @@ class MainActivity : AppCompatActivity() {
         ThemeSettingsStorage.initialize(applicationContext)
         super.onCreate(savedInstanceState)
         window.setBackgroundDrawableResource(R.color.nuvio_background)
+        SyncClientIdentityStorage.initialize(applicationContext)
         AddonStorage.initialize(applicationContext)
         AuthStorage.initialize(applicationContext)
         LibraryStorage.initialize(applicationContext)
diff --git a/composeApp/src/androidMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.android.kt b/composeApp/src/androidMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.android.kt
new file mode 100644
index 00000000..6dae30d5
--- /dev/null
+++ b/composeApp/src/androidMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.android.kt
@@ -0,0 +1,25 @@
+package com.nuvio.app.core.sync
+
+import android.content.Context
+import android.content.SharedPreferences
+
+actual object SyncClientIdentityStorage {
+    private const val preferencesName = "nuvio_sync_client_identity"
+    private const val clientIdKey = "client_instance_id"
+
+    private var preferences: SharedPreferences? = null
+
+    fun initialize(context: Context) {
+        preferences = context.getSharedPreferences(preferencesName, Context.MODE_PRIVATE)
+    }
+
+    actual fun loadClientId(): String? =
+        preferences?.getString(clientIdKey, null)
+
+    actual fun saveClientId(clientId: String) {
+        preferences
+            ?.edit()
+            ?.putString(clientIdKey, clientId)
+            ?.apply()
+    }
+}
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/ProfileSettingsSync.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/ProfileSettingsSync.kt
index 26616f91..083a4027 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/ProfileSettingsSync.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/ProfileSettingsSync.kt
@@ -206,6 +206,7 @@ object ProfileSettingsSync {
             put("p_profile_id", profileId)
             put("p_platform", MOBILE_SYNC_PLATFORM)
             put("p_settings_json", json.encodeToJsonElement(MobileProfileSettingsBlob.serializer(), blob))
+            putSyncOriginClientId()
         }
         SupabaseProvider.client.postgrest.rpc("sync_push_profile_settings_blob", params)
         log.d { "pushToRemoteLocked(profileId=$profileId) — success" }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/RealtimeSyncInvalidationService.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/RealtimeSyncInvalidationService.kt
index 1bad1c4d..145c30c0 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/RealtimeSyncInvalidationService.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/RealtimeSyncInvalidationService.kt
@@ -135,13 +135,19 @@ object RealtimeSyncInvalidationService {
     private fun handleInsert(profileId: Int, record: JsonObject) {
         val eventId = record["id"]?.jsonPrimitive?.contentOrNull
         val createdAt = record["created_at"]?.jsonPrimitive?.contentOrNull
+        val originClientId = record["origin_client_id"]?.jsonPrimitive?.contentOrNull
+        if (originClientId != null && originClientId == SyncClientIdentity.currentClientId()) {
+            log.d { "Ignoring self-originated sync invalidation id=$eventId originClientId=$originClientId" }
+            return
+        }
         val surface = record["surface"]?.jsonPrimitive?.contentOrNull ?: run {
             log.w { "Received sync invalidation without surface id=$eventId createdAt=$createdAt keys=${record.keys}" }
             return
         }
         val eventProfileId = record["profile_id"]?.jsonPrimitive?.intOrNull
         log.i {
-            "Received sync invalidation id=$eventId surface=$surface eventProfile=$eventProfileId activeProfile=$profileId createdAt=$createdAt"
+            "Received sync invalidation id=$eventId surface=$surface eventProfile=$eventProfileId " +
+                "activeProfile=$profileId originClientId=$originClientId createdAt=$createdAt"
         }
         if (surface != "profiles" && eventProfileId != null && eventProfileId != profileId) {
             log.d { "Ignoring sync invalidation id=$eventId for inactive profile $eventProfileId" }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentity.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentity.kt
new file mode 100644
index 00000000..c116f88b
--- /dev/null
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentity.kt
@@ -0,0 +1,50 @@
+package com.nuvio.app.core.sync
+
+import kotlinx.serialization.json.JsonObjectBuilder
+import kotlinx.serialization.json.put
+import kotlin.random.Random
+
+private const val CLIENT_ID_LENGTH = 32
+private const val CLIENT_ID_PREFIX = "nuvio-mobile-"
+private const val ORIGIN_CLIENT_ID_PARAM = "p_origin_client_id"
+private const val CLIENT_ID_ALPHABET = "abcdefghijklmnopqrstuvwxyz0123456789"
+
+object SyncClientIdentity {
+    private var cachedClientId: String? = null
+
+    fun currentClientId(): String {
+        cachedClientId?.let { return it }
+
+        val stored = SyncClientIdentityStorage.loadClientId()
+            ?.trim()
+            ?.takeIf { it.isValidSyncClientId() }
+        if (stored != null) {
+            cachedClientId = stored
+            return stored
+        }
+
+        val generated = generateClientId()
+        SyncClientIdentityStorage.saveClientId(generated)
+        cachedClientId = generated
+        return generated
+    }
+
+    private fun generateClientId(): String =
+        CLIENT_ID_PREFIX + buildString(CLIENT_ID_LENGTH) {
+            repeat(CLIENT_ID_LENGTH) {
+                append(CLIENT_ID_ALPHABET[Random.nextInt(CLIENT_ID_ALPHABET.length)])
+            }
+        }
+
+    private fun String.isValidSyncClientId(): Boolean =
+        length in 16..96 && all { it.isLetterOrDigit() || it == '-' || it == '_' }
+}
+
+internal fun JsonObjectBuilder.putSyncOriginClientId() {
+    put(ORIGIN_CLIENT_ID_PARAM, SyncClientIdentity.currentClientId())
+}
+
+internal expect object SyncClientIdentityStorage {
+    fun loadClientId(): String?
+    fun saveClientId(clientId: String)
+}
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/addons/AddonRepository.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/addons/AddonRepository.kt
index f430f3ed..42d2875c 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/addons/AddonRepository.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/addons/AddonRepository.kt
@@ -2,6 +2,7 @@ package com.nuvio.app.features.addons
 
 import co.touchlab.kermit.Logger
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.profiles.ProfileRepository
 import io.github.jan.supabase.postgrest.postgrest
 import io.github.jan.supabase.postgrest.query.Order
@@ -151,6 +152,7 @@ object AddonRepository {
                     val params = buildJsonObject {
                         put("p_profile_id", currentProfileId)
                         put("p_addons", json.encodeToJsonElement(addons))
+                        putSyncOriginClientId()
                     }
                     SupabaseProvider.client.postgrest.rpc("sync_push_addons", params)
                     log.i { "pullFromServer() — migration push done (${addons.size} addons)" }
@@ -396,6 +398,7 @@ object AddonRepository {
                 val params = buildJsonObject {
                     put("p_profile_id", profileId)
                     put("p_addons", json.encodeToJsonElement(addons))
+                    putSyncOriginClientId()
                 }
                 SupabaseProvider.client.postgrest.rpc("sync_push_addons", params)
                 log.d { "pushToServer() — success" }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/collection/CollectionSyncService.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/collection/CollectionSyncService.kt
index 76aac768..e756a1f0 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/collection/CollectionSyncService.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/collection/CollectionSyncService.kt
@@ -4,6 +4,7 @@ import co.touchlab.kermit.Logger
 import com.nuvio.app.core.auth.AuthRepository
 import com.nuvio.app.core.auth.AuthState
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.profiles.ProfileRepository
 import io.github.jan.supabase.postgrest.postgrest
 import io.github.jan.supabase.postgrest.rpc
@@ -117,6 +118,7 @@ object CollectionSyncService {
             val params = buildJsonObject {
                 put("p_profile_id", profileId)
                 put("p_collections_json", jsonElement)
+                putSyncOriginClientId()
             }
             SupabaseProvider.client.postgrest.rpc("sync_push_collections", params)
             log.d { "pushToRemote — success" }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/home/HomeCatalogSettingsSyncService.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/home/HomeCatalogSettingsSyncService.kt
index 15f5ffc7..d9edcea8 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/home/HomeCatalogSettingsSyncService.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/home/HomeCatalogSettingsSyncService.kt
@@ -6,6 +6,7 @@ import com.nuvio.app.core.auth.AuthState
 import com.nuvio.app.core.network.SupabaseProvider
 import com.nuvio.app.core.sync.HOME_CATALOG_LEGACY_SYNC_PLATFORMS
 import com.nuvio.app.core.sync.HOME_CATALOG_SHARED_SYNC_PLATFORM
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.profiles.ProfileRepository
 import io.github.jan.supabase.postgrest.postgrest
 import io.github.jan.supabase.postgrest.rpc
@@ -136,6 +137,7 @@ object HomeCatalogSettingsSyncService {
                 put("p_profile_id", profileId)
                 put("p_platform", HOME_CATALOG_SHARED_SYNC_PLATFORM)
                 put("p_settings_json", jsonElement)
+                putSyncOriginClientId()
             }
             SupabaseProvider.client.postgrest.rpc("sync_push_home_catalog_settings", params)
             log.d { "pushToRemote — success" }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/library/LibraryRepository.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/library/LibraryRepository.kt
index 1c854f47..bafc1244 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/library/LibraryRepository.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/library/LibraryRepository.kt
@@ -5,6 +5,7 @@ import com.nuvio.app.core.auth.AuthRepository
 import com.nuvio.app.core.ui.NuvioToastController
 import com.nuvio.app.core.auth.AuthState
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.home.PosterShape
 import com.nuvio.app.features.profiles.ProfileRepository
 import com.nuvio.app.features.trakt.TraktAuthRepository
@@ -421,6 +422,7 @@ object LibraryRepository {
                 val params = buildJsonObject {
                     put("p_profile_id", profileId)
                     put("p_items", json.encodeToJsonElement(syncItems))
+                    putSyncOriginClientId()
                 }
                 log.i { "Pushing library to server profile=$profileId itemCount=${syncItems.size}" }
                 SupabaseProvider.client.postgrest.rpc("sync_push_library", params)
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
index 279c1080..cd727a95 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/profiles/ProfileRepository.kt
@@ -5,6 +5,7 @@ import com.nuvio.app.core.auth.AuthRepository
 import com.nuvio.app.core.auth.AuthState
 import com.nuvio.app.core.auth.isAnonymous
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.addons.AddonRepository
 import com.nuvio.app.features.collection.CollectionMobileSettingsRepository
 import com.nuvio.app.features.collection.CollectionRepository
@@ -187,6 +188,7 @@ object ProfileRepository {
             val params = buildJsonObject {
                 put("p_client_max_profiles", MAX_PROFILES)
                 put("p_profiles", json.encodeToJsonElement(profiles))
+                putSyncOriginClientId()
             }
             SupabaseProvider.client.postgrest.rpc("sync_push_profiles", params)
             pullProfiles()
@@ -277,7 +279,10 @@ object ProfileRepository {
             return
         }
         try {
-            val params = buildJsonObject { put("p_profile_id", profileIndex) }
+            val params = buildJsonObject {
+                put("p_profile_id", profileIndex)
+                putSyncOriginClientId()
+            }
             SupabaseProvider.client.postgrest.rpc("sync_delete_profile_data", params)
             pullProfiles()
         } catch (e: Throwable) {
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseProgressSyncAdapter.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseProgressSyncAdapter.kt
index 8521e4cd..476bc766 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseProgressSyncAdapter.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseProgressSyncAdapter.kt
@@ -1,6 +1,7 @@
 package com.nuvio.app.features.watching.sync
 
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.watchprogress.WatchProgressEntry
 import io.github.jan.supabase.postgrest.postgrest
 import io.github.jan.supabase.postgrest.rpc
@@ -104,6 +105,7 @@ object SupabaseProgressSyncAdapter : ProgressSyncAdapter {
         val params = buildJsonObject {
             put("p_profile_id", profileId)
             put("p_entries", json.encodeToJsonElement(syncEntries))
+            putSyncOriginClientId()
         }
         SupabaseProvider.client.postgrest.rpc("sync_push_watch_progress", params)
     }
@@ -122,6 +124,7 @@ object SupabaseProgressSyncAdapter : ProgressSyncAdapter {
         val params = buildJsonObject {
             put("p_profile_id", profileId)
             put("p_keys", json.encodeToJsonElement(progressKeys))
+            putSyncOriginClientId()
         }
         SupabaseProvider.client.postgrest.rpc("sync_delete_watch_progress", params)
     }
diff --git a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseWatchedSyncAdapter.kt b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseWatchedSyncAdapter.kt
index a9b52395..76f8a5c8 100644
--- a/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseWatchedSyncAdapter.kt
+++ b/composeApp/src/commonMain/kotlin/com/nuvio/app/features/watching/sync/SupabaseWatchedSyncAdapter.kt
@@ -1,6 +1,7 @@
 package com.nuvio.app.features.watching.sync
 
 import com.nuvio.app.core.network.SupabaseProvider
+import com.nuvio.app.core.sync.putSyncOriginClientId
 import com.nuvio.app.features.watched.WatchedItem
 import com.nuvio.app.features.watched.normalizeWatchedMarkedAtEpochMs
 import io.github.jan.supabase.postgrest.postgrest
@@ -102,6 +103,7 @@ object SupabaseWatchedSyncAdapter : WatchedSyncAdapter {
         val params = buildJsonObject {
             put("p_profile_id", profileId)
             put("p_items", json.encodeToJsonElement(syncItems))
+            putSyncOriginClientId()
         }
         SupabaseProvider.client.postgrest.rpc("sync_push_watched_items", params)
     }
@@ -120,6 +122,7 @@ object SupabaseWatchedSyncAdapter : WatchedSyncAdapter {
         val params = buildJsonObject {
             put("p_profile_id", profileId)
             put("p_keys", json.encodeToJsonElement(keys))
+            putSyncOriginClientId()
         }
         SupabaseProvider.client.postgrest.rpc("sync_delete_watched_items", params)
     }
diff --git a/composeApp/src/iosMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.ios.kt b/composeApp/src/iosMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.ios.kt
new file mode 100644
index 00000000..f3c2f444
--- /dev/null
+++ b/composeApp/src/iosMain/kotlin/com/nuvio/app/core/sync/SyncClientIdentityStorage.ios.kt
@@ -0,0 +1,14 @@
+package com.nuvio.app.core.sync
+
+import platform.Foundation.NSUserDefaults
+
+actual object SyncClientIdentityStorage {
+    private const val clientIdKey = "client_instance_id"
+
+    actual fun loadClientId(): String? =
+        NSUserDefaults.standardUserDefaults.stringForKey(clientIdKey)
+
+    actual fun saveClientId(clientId: String) {
+        NSUserDefaults.standardUserDefaults.setObject(clientId, forKey = clientIdKey)
+    }
+}