diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStore.java b/service/src/main/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStore.java
index 5b0e4a9a2..376c41563 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStore.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStore.java
@@ -111,8 +111,6 @@ public class FoundationDbMessageStore {
         new ArrayList<>();
 
     messagesByShardId.forEach((shardId, messagesForShard) -> {
-      final Database shard = databases[shardId];
-
       int start = 0, current = 0;
       int estimatedTransactionSize = 0;
 
@@ -123,7 +121,7 @@ public class FoundationDbMessageStore {
             .sum();
 
         if (estimatedTransactionSize > MAX_MESSAGE_CHUNK_SIZE) {
-          chunkFutures.add(insertChunk(shard, messagesForShard.subList(start, current)));
+          chunkFutures.add(insertChunk(shardId, messagesForShard.subList(start, current)));
 
           start = current;
           estimatedTransactionSize = 0;
@@ -133,7 +131,7 @@ public class FoundationDbMessageStore {
       }
 
       assert start < messagesForShard.size();
-      chunkFutures.add(insertChunk(shard, messagesForShard.subList(start, messagesForShard.size())));
+      chunkFutures.add(insertChunk(shardId, messagesForShard.subList(start, messagesForShard.size())));
     });
 
     return CompletableFuture.allOf(chunkFutures.toArray(CompletableFuture[]::new))
@@ -146,7 +144,7 @@ public class FoundationDbMessageStore {
   }
 
   private CompletableFuture<Map<AciServiceIdentifier, Map<Byte, InsertResult>>> insertChunk(
-      final Database database,
+      final int shardId,
       final List<Map.Entry<AciServiceIdentifier, Map<Byte, MessageProtos.Envelope>>> messagesByAccountIdentifier) {
 
     final Map<AciServiceIdentifier, CompletableFuture<Map<Byte, Boolean>>> insertFuturesByAci = new HashMap<>();
@@ -158,7 +156,7 @@ public class FoundationDbMessageStore {
         .map(MessageProtos.Envelope::getEphemeral)
         .orElseThrow(() -> new IllegalStateException("One or more bundles is empty"));
 
-    return database.runAsync(transaction -> {
+    return databases[shardId].runAsync(transaction -> {
           messagesByAccountIdentifier.forEach(entry ->
               insertFuturesByAci.put(entry.getKey(), insert(entry.getKey(), entry.getValue(), transaction)));
 
@@ -171,7 +169,7 @@ public class FoundationDbMessageStore {
                     .anyMatch(isPresent -> isPresent);
                 if (anyClientPresent || !ephemeral) {
                   return transaction.getVersionstamp()
-                      .thenApply(versionstampBytes -> Optional.of(Versionstamp.complete(versionstampBytes)));
+                      .thenApply(versionstampBytes -> Optional.of(Versionstamp.complete(versionstampBytes, shardId)));
                 }
                 return CompletableFuture.completedFuture(Optional.<Versionstamp>empty());
               });
@@ -222,7 +220,7 @@ public class FoundationDbMessageStore {
                 if (isPresent || !message.getEphemeral()) {
                   transaction.mutate(MutationType.SET_VERSIONSTAMPED_KEY,
                       getDeviceQueueSubspace(aci, deviceId)
-                          .packWithVersionstamp(Tuple.from(Versionstamp.incomplete())), message.toByteArray());
+                          .packWithVersionstamp(Tuple.from(Versionstamp.incomplete(hashAciToShardNumber(aci)))), message.toByteArray());
                 }
 
                 return isPresent;
@@ -241,7 +239,7 @@ public class FoundationDbMessageStore {
 
           if (anyClientPresent) {
             transaction.mutate(MutationType.SET_VERSIONSTAMPED_VALUE, getMessagesAvailableWatchKey(aci),
-                Tuple.from(Versionstamp.incomplete()).packWithVersionstamp());
+                Tuple.from(Versionstamp.incomplete(hashAciToShardNumber(aci))).packWithVersionstamp());
           }
 
           return presenceByDeviceId;
diff --git a/service/src/test/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStoreTest.java b/service/src/test/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStoreTest.java
index b47f62b49..d2396b05f 100644
--- a/service/src/test/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStoreTest.java
+++ b/service/src/test/java/org/whispersystems/textsecuregcm/storage/foundationdb/FoundationDbMessageStoreTest.java
@@ -74,23 +74,34 @@ class FoundationDbMessageStoreTest {
 
   @ParameterizedTest
   @MethodSource
-  void insert(final long presenceUpdatedBeforeSeconds, final boolean ephemeral, final boolean expectMessagesInserted,
-      final boolean expectVersionstampUpdated, final boolean expectPresenceState) {
+  void insert(final long presenceUpdatedBeforeSeconds,
+      final boolean ephemeral,
+      final boolean expectMessagesInserted,
+      final boolean expectVersionstampUpdated,
+      final boolean expectPresenceState) {
+
     final AciServiceIdentifier aci = new AciServiceIdentifier(UUID.randomUUID());
     final List<Byte> deviceIds = IntStream.range(Device.PRIMARY_ID, Device.PRIMARY_ID + 6)
         .mapToObj(i -> (byte) i)
         .toList();
+
     deviceIds.forEach(deviceId -> writePresenceKey(aci, deviceId, 1, presenceUpdatedBeforeSeconds));
+
     final Map<Byte, MessageProtos.Envelope> messagesByDeviceId = deviceIds.stream()
         .collect(Collectors.toMap(Function.identity(), _ -> generateRandomMessage(ephemeral)));
-    final Map<Byte, FoundationDbMessageStore.InsertResult> result = foundationDbMessageStore.insert(aci, messagesByDeviceId).join();
-    assertNotNull(result);
+
+    final Map<Byte, FoundationDbMessageStore.InsertResult> result =
+        foundationDbMessageStore.insert(aci, messagesByDeviceId).join();
+
+    assertTrue(result.keySet().containsAll(deviceIds));
 
     final Optional<Versionstamp> returnedVersionstamp = result.values().stream().findFirst()
         .flatMap(FoundationDbMessageStore.InsertResult::versionstamp);
+
     if (expectMessagesInserted) {
       assertTrue(returnedVersionstamp.isPresent());
       assertTrue(result.values().stream().allMatch(insertResult -> returnedVersionstamp.equals(insertResult.versionstamp())));
+
       final Map<Byte, MessageProtos.Envelope> storedMessagesByDeviceId = deviceIds.stream()
           .collect(Collectors.toMap(Function.identity(), deviceId -> {
             try {
@@ -109,7 +120,7 @@ class FoundationDbMessageStoreTest {
     if (expectVersionstampUpdated) {
       final Optional<Versionstamp> messagesAvailableWatchVersionstamp = getMessagesAvailableWatch(aci);
       assertTrue(messagesAvailableWatchVersionstamp.isPresent());
-      assertEquals(returnedVersionstamp, messagesAvailableWatchVersionstamp,
+      assertEquals(messagesAvailableWatchVersionstamp, returnedVersionstamp,
           "messages available versionstamp should be the versionstamp of the last insert transaction");
     } else {
       assertTrue(getMessagesAvailableWatch(aci).isEmpty());