diff --git a/docs/sdk/sdk-parity-manifest.json b/docs/sdk/sdk-parity-manifest.json
index 26101839912..ddc1d05d764 100644
--- a/docs/sdk/sdk-parity-manifest.json
+++ b/docs/sdk/sdk-parity-manifest.json
@@ -32,6 +32,7 @@
     "platform_wallet_manager_create_with_persistence_capabilities": "packages/rs-platform-wallet-ffi/src/manager.rs",
     "platform_wallet_manager_persistence_capabilities": "packages/rs-platform-wallet-ffi/src/manager.rs",
     "platform_wallet_manager_spv_rescan_filters": "packages/rs-platform-wallet-ffi/src/spv.rs",
+    "platform_wallet_manager_sync_fault_detected": "packages/rs-platform-wallet-ffi/src/manager.rs",
     "platform_wallet_resume_identity_with_existing_asset_lock_signer": "packages/rs-platform-wallet-ffi/src/identity_registration_funded_with_signer.rs",
     "platform_wallet_sync_contested_dpns_names": "packages/rs-platform-wallet-ffi/src/dpns.rs",
     "platform_wallet_token_purchase": "packages/rs-platform-wallet-ffi/src/tokens/purchase.rs",
@@ -811,6 +812,63 @@
         }
       ]
     },
+    {
+      "id": "persistence.sync_fault_latch",
+      "title": "Watermark-freeze sync fault latch is host-visible",
+      "area": "recovery",
+      "shared_apis": [
+        "platform_wallet_manager_sync_fault_detected"
+      ],
+      "required_persistence_capabilities": [],
+      "hosts": {
+        "swift": {
+          "sdk": "supported",
+          "example_app": "not-applicable",
+          "restart": "not_applicable",
+          "reason": null
+        },
+        "kotlin": {
+          "sdk": "supported",
+          "example_app": "not-applicable",
+          "restart": "not_applicable",
+          "reason": null
+        }
+      },
+      "verification": [
+        {
+          "host": "swift",
+          "kind": "unit",
+          "file": "packages/swift-sdk/SwiftTests/SwiftDashSDKTests/SyncFaultDetectedTests.swift",
+          "id": "testSyncFaultDetectedRequiresConfiguredManager",
+          "command": "cd packages/swift-sdk && xcodebuild test -scheme SwiftDashSDK -destination 'platform=iOS Simulator,name=iPhone 17 Pro' -only-testing:SwiftDashSDKTests/SyncFaultDetectedTests",
+          "covers_restart": false
+        },
+        {
+          "host": "kotlin",
+          "kind": "device",
+          "file": "packages/kotlin-sdk/sdk/src/androidTest/kotlin/org/dashfoundation/dashsdk/FfiSmokeTest.kt",
+          "id": "syncFaultDetectedSymbolBindsAndRejectsInvalidHandle",
+          "command": "cd packages/kotlin-sdk && ./gradlew :sdk:connectedDebugAndroidTest",
+          "covers_restart": false
+        },
+        {
+          "host": "shared",
+          "kind": "unit",
+          "file": "packages/rs-platform-wallet/src/changeset/core_bridge.rs",
+          "id": "lagged_broadcast_freezes_and_strips_subsequent_watermark",
+          "command": "cargo test -p platform-wallet lagged_broadcast_freezes_and_strips_subsequent_watermark",
+          "covers_restart": false
+        },
+        {
+          "host": "shared",
+          "kind": "unit",
+          "file": "packages/rs-platform-wallet/src/changeset/core_bridge.rs",
+          "id": "rejected_store_freezes_wallet_and_strips_watermark",
+          "command": "cargo test -p platform-wallet rejected_store_freezes_wallet_and_strips_watermark",
+          "covers_restart": false
+        }
+      ]
+    },
     {
       "id": "network.masternode_discovery",
       "title": "Canonical masternode endpoint discovery",
diff --git a/packages/kotlin-sdk/PARITY_SUMMARY.md b/packages/kotlin-sdk/PARITY_SUMMARY.md
index 2ac15049f5c..11057ae22a1 100644
--- a/packages/kotlin-sdk/PARITY_SUMMARY.md
+++ b/packages/kotlin-sdk/PARITY_SUMMARY.md
@@ -2,23 +2,23 @@
 # Kotlin/Swift executable parity summary
 
 Audit baseline: `PR #3999 @ 6dbc72a54df72d26eb9c4a014b425d2b95134e4e`
-Capabilities tracked: **22**
+Capabilities tracked: **23**
 
 ## Status counts
 
 | Host | Surface | Supported | Partial | Unsupported | Not applicable |
 | --- | --- | ---: | ---: | ---: | ---: |
-| Swift | SDK | 12 | 8 | 1 | 1 |
-| Swift | Example app | 4 | 12 | 1 | 5 |
-| Kotlin | SDK | 10 | 12 | 0 | 0 |
-| Kotlin | Example app | 5 | 12 | 0 | 5 |
+| Swift | SDK | 13 | 8 | 1 | 1 |
+| Swift | Example app | 4 | 12 | 1 | 6 |
+| Kotlin | SDK | 11 | 12 | 0 | 0 |
+| Kotlin | Example app | 5 | 12 | 0 | 6 |
 
 ## Restart coverage
 
 | Host | Tested | Required | Not applicable |
 | --- | ---: | ---: | ---: |
-| Swift | 0 | 7 | 15 |
-| Kotlin | 4 | 6 | 12 |
+| Swift | 0 | 7 | 16 |
+| Kotlin | 4 | 6 | 13 |
 
 ## Capability status
 
@@ -34,6 +34,7 @@ Capabilities tracked: **22**
 | `identity.asset_lock_resume` | supported / partial / required | partial / partial / required |
 | `core.compact_filter_rescan` | supported / partial / not_applicable | partial / partial / not_applicable |
 | `dpns.contested_names_by_identity` | supported / partial / not_applicable | partial / partial / required |
+| `persistence.sync_fault_latch` | supported / not-applicable / not_applicable | supported / not-applicable / not_applicable |
 | `network.masternode_discovery` | partial / not-applicable / not_applicable | partial / not-applicable / not_applicable |
 | `identity.platform_address_auto_funding` | partial / partial / not_applicable | partial / partial / not_applicable |
 | `tokens.authorization_decisions` | partial / partial / not_applicable | partial / partial / not_applicable |
diff --git a/packages/kotlin-sdk/sdk/src/androidTest/kotlin/org/dashfoundation/dashsdk/FfiSmokeTest.kt b/packages/kotlin-sdk/sdk/src/androidTest/kotlin/org/dashfoundation/dashsdk/FfiSmokeTest.kt
index 1e561ee35d6..d9bfe5ee81b 100644
--- a/packages/kotlin-sdk/sdk/src/androidTest/kotlin/org/dashfoundation/dashsdk/FfiSmokeTest.kt
+++ b/packages/kotlin-sdk/sdk/src/androidTest/kotlin/org/dashfoundation/dashsdk/FfiSmokeTest.kt
@@ -3,6 +3,7 @@ package org.dashfoundation.dashsdk
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import kotlinx.coroutines.Dispatchers
+import org.dashfoundation.dashsdk.ffi.DashSDKException
 import org.dashfoundation.dashsdk.ffi.NativeLoader
 import org.dashfoundation.dashsdk.ffi.SdkNative
 import org.dashfoundation.dashsdk.ffi.SignerNative
@@ -13,6 +14,7 @@ import org.junit.Assert.assertEquals
 import org.junit.Assert.assertNotEquals
 import org.junit.Assert.assertNotNull
 import org.junit.Assert.assertNull
+import org.junit.Assert.assertThrows
 import org.junit.Assert.assertTrue
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -84,6 +86,22 @@ class FfiSmokeTest {
         assertEquals("compact recoverable ECDSA signature", 65, signature!!.size)
     }
 
+    /**
+     * The #4069 watermark-freeze fault latch surfaced by PR #4314: the
+     * `syncFaultDetected` JNI symbol binds, and an invalid manager handle
+     * surfaces as the mapped [DashSDKException] rather than a crash. The
+     * latch behavior itself (freeze on dropped events / rejected store) is
+     * covered by the shared Rust tests in
+     * `packages/rs-platform-wallet/src/changeset/core_bridge.rs`.
+     */
+    @Test
+    fun syncFaultDetectedSymbolBindsAndRejectsInvalidHandle() {
+        NativeLoader.ensureLoaded()
+        assertThrows(DashSDKException::class.java) {
+            WalletManagerNative.syncFaultDetected(0L)
+        }
+    }
+
     /**
      * Rust↔Kotlin persistence-descriptor lockstep. The trampolines resolve
      * each bridge method by (name, descriptor) only when its slot first
diff --git a/packages/swift-sdk/Sources/SwiftDashSDK/PlatformWallet/PlatformWalletManagerAddressSync.swift b/packages/swift-sdk/Sources/SwiftDashSDK/PlatformWallet/PlatformWalletManagerAddressSync.swift
index 90550d26e2d..c03f37f2aae 100644
--- a/packages/swift-sdk/Sources/SwiftDashSDK/PlatformWallet/PlatformWalletManagerAddressSync.swift
+++ b/packages/swift-sdk/Sources/SwiftDashSDK/PlatformWallet/PlatformWalletManagerAddressSync.swift
@@ -184,6 +184,28 @@ extension PlatformWalletManager {
         return running
     }
 
+    /// Whether the native manager has frozen its durable sync watermark this
+    /// session (dashpay/platform#4069). `true` means the wallet-event adapter
+    /// dropped record-bearing events, or a persistence `store()` was rejected,
+    /// so the persisted `syncedHeight` is deliberately held behind the chain
+    /// tip and a rescan is pending on the next launch. Poll this to surface a
+    /// hard "verification failed / rescan pending" state instead of leaving
+    /// the fault visible only in the error logs.
+    ///
+    /// The flag latches for this native manager's lifetime: once `true` it stays
+    /// `true` until the manager is destroyed.
+    public func syncFaultDetected() throws -> Bool {
+        guard isConfigured, handle != NULL_HANDLE else {
+            throw PlatformWalletError.invalidHandle(
+                "PlatformWalletManager not configured"
+            )
+        }
+
+        var detected = false
+        try platform_wallet_manager_sync_fault_detected(handle, &detected).check()
+        return detected
+    }
+
     public func isPlatformAddressSyncing() throws -> Bool {
         guard isConfigured, handle != NULL_HANDLE else {
             throw PlatformWalletError.invalidHandle(
diff --git a/packages/swift-sdk/SwiftTests/SwiftDashSDKTests/SyncFaultDetectedTests.swift b/packages/swift-sdk/SwiftTests/SwiftDashSDKTests/SyncFaultDetectedTests.swift
new file mode 100644
index 00000000000..784e3d91ea9
--- /dev/null
+++ b/packages/swift-sdk/SwiftTests/SwiftDashSDKTests/SyncFaultDetectedTests.swift
@@ -0,0 +1,45 @@
+// SyncFaultDetectedTests.swift
+// SwiftDashSDKTests
+//
+// Unit tests for the `PlatformWalletManager.syncFaultDetected()` FFI bridge.
+
+import XCTest
+@testable import SwiftDashSDK
+
+/// Coverage for the Swift side of the watermark-freeze fault latch
+/// (dashpay/platform#4069), exported over the C ABI by PR #4314 as
+/// `platform_wallet_manager_sync_fault_detected`.
+///
+/// `syncFaultDetected()` is a pure bridge: guard the handle, call the export,
+/// return the out-param. The latch's actual semantics — the persisted
+/// `syncedHeight` being deliberately held behind the chain tip after the
+/// wallet-event adapter drops record-bearing events or a persistence `store()`
+/// is rejected, and the flag latching `true` for the process lifetime — live in
+/// Rust and are covered by the shared tests in
+/// `packages/rs-platform-wallet/src/changeset/core_bridge.rs`. What is Swift's
+/// to get right is the unconfigured-handle guard, which must throw rather than
+/// hand `NULL_HANDLE` across the FFI boundary.
+///
+/// `PlatformWalletManager` is main-actor isolated, so the suite runs on the
+/// main actor.
+@MainActor
+final class SyncFaultDetectedTests: XCTestCase {
+
+    /// A bare `PlatformWalletManager()` has never been configured: `handle` is
+    /// `NULL_HANDLE` and `isConfigured` is false, so the wrapper must throw
+    /// `PlatformWalletError.invalidHandle` instead of calling the export with
+    /// a null handle.
+    func testSyncFaultDetectedRequiresConfiguredManager() {
+        let manager = PlatformWalletManager()
+        XCTAssertFalse(manager.isConfigured, "a bare manager is unconfigured")
+
+        XCTAssertThrowsError(try manager.syncFaultDetected()) { error in
+            XCTAssertTrue(error is PlatformWalletError)
+            if case PlatformWalletError.invalidHandle = error {
+                // Expected error
+            } else {
+                XCTFail("Expected invalidHandle error, got \(error)")
+            }
+        }
+    }
+}