diff --git a/waku/node/waku_node.nim b/waku/node/waku_node.nim
index ac72f3e37..39948913d 100644
--- a/waku/node/waku_node.nim
+++ b/waku/node/waku_node.nim
@@ -521,7 +521,7 @@ proc mountFilterClient*(node: WakuNode) {.async: (raises: []).} =
 
 proc filterSubscribe*(
     node: WakuNode,
-    pubsubTopic: Option[PubsubTopic],
+    shard: Option[RelayShard],
     contentTopics: ContentTopic | seq[ContentTopic],
     peer: RemotePeerInfo | string,
 ): Future[FilterSubscribeResult] {.async: (raises: []).} =
@@ -604,6 +604,15 @@ proc filterSubscribe*(
     # return the last error or ok
     return subRes
 
+# proc filterSubscribe* {.deprecated: "Pass a shard instead of a pubsubtopic".} (
+#     node: WakuNode,
+#     pubsubTopic: Option[PubsubTopic],
+#     contentTopics: ContentTopic | seq[ContentTopic],
+#     peer: RemotePeerInfo | string,
+# ): Future[FilterSubscribeResult] {.async: (raises: []).} =
+
+#   echo "TODO"
+
 proc filterUnsubscribe*(
     node: WakuNode,
     pubsubTopic: Option[PubsubTopic],
diff --git a/waku/waku_core/message/digest.nim b/waku/waku_core/message/digest.nim
index 8b99abd7e..4a026b84b 100644
--- a/waku/waku_core/message/digest.nim
+++ b/waku/waku_core/message/digest.nim
@@ -59,6 +59,9 @@ proc computeMessageHash*(pubsubTopic: PubsubTopic, msg: WakuMessage): WakuMessag
 
   return ctx.finish() # Computes the hash
 
+proc computeMessageHash*(shard: RelayShard, msg: WakuMessage): WakuMessageHash =
+  return computeMessageHash(shard.toPubsubTopic(), msg)
+
 proc cmp*(x, y: WakuMessageHash): int =
   if x < y:
     return -1
diff --git a/waku/waku_filter_v2/protocol.nim b/waku/waku_filter_v2/protocol.nim
index 80f60fdd3..ffb3d4773 100644
--- a/waku/waku_filter_v2/protocol.nim
+++ b/waku/waku_filter_v2/protocol.nim
@@ -45,17 +45,11 @@ proc setSubscriptionTimeout*(wf: WakuFilter, newTimeout: Duration) =
   wf.subscriptions.setSubscriptionTimeout(newTimeout)
 
 proc subscribe(
-    wf: WakuFilter,
-    peerId: PeerID,
-    pubsubTopic: Option[PubsubTopic],
-    contentTopics: seq[ContentTopic],
+    wf: WakuFilter, peerId: PeerID, shard: RelayShard, contentTopics: seq[ContentTopic]
 ): Future[FilterSubscribeResult] {.async.} =
-  # TODO: check if this condition is valid???
-  if pubsubTopic.isNone() or contentTopics.len == 0:
-    error "pubsubTopic and contentTopics must be specified", peerId = peerId
-    return err(
-      FilterSubscribeError.badRequest("pubsubTopic and contentTopics must be specified")
-    )
+  if contentTopics.len == 0:
+    error "contentTopics must be specified", peerId = peerId
+    return err(FilterSubscribeError.badRequest("contentTopics must be specified"))
 
   if contentTopics.len > MaxContentTopicsPerRequest:
     error "exceeds maximum content topics", peerId = peerId
@@ -65,7 +59,7 @@ proc subscribe(
       )
     )
 
-  let filterCriteria = toHashSet(contentTopics.mapIt((pubsubTopic.get(), it)))
+  let filterCriteria = toHashSet(contentTopics.mapIt((shard, it)))
 
   debug "subscribing peer to filter criteria",
     peerId = peerId, filterCriteria = filterCriteria
@@ -78,16 +72,11 @@ proc subscribe(
   ok()
 
 proc unsubscribe(
-    wf: WakuFilter,
-    peerId: PeerID,
-    pubsubTopic: Option[PubsubTopic],
-    contentTopics: seq[ContentTopic],
+    wf: WakuFilter, peerId: PeerID, shard: RelayShard, contentTopics: seq[ContentTopic]
 ): FilterSubscribeResult =
-  if pubsubTopic.isNone() or contentTopics.len == 0:
-    error "pubsubTopic and contentTopics must be specified", peerId = peerId
-    return err(
-      FilterSubscribeError.badRequest("pubsubTopic and contentTopics must be specified")
-    )
+  if contentTopics.len == 0:
+    error "contentTopics must be specified", peerId = peerId
+    return err(FilterSubscribeError.badRequest("contentTopics must be specified"))
 
   if contentTopics.len > MaxContentTopicsPerRequest:
     error "exceeds maximum content topics", peerId = peerId
@@ -97,7 +86,7 @@ proc unsubscribe(
       )
     )
 
-  let filterCriteria = toHashSet(contentTopics.mapIt((pubsubTopic.get(), it)))
+  let filterCriteria = toHashSet(contentTopics.mapIt((shard, it)))
 
   debug "unsubscribing peer from filter criteria",
     peerId = peerId, filterCriteria = filterCriteria
@@ -125,6 +114,17 @@ proc unsubscribeAll(
 
   ok()
 
+proc getShardFromRequest(
+    request: FilterSubscribeRequest
+): Result[RelayShard, FilterSubscribeError] =
+  if request.pubsubTopic.isNone():
+    return err(FilterSubscribeError.badRequest("Pubsub topic must be specified"))
+  else:
+    let shard = RelayShard.parseStaticSharding(request.pubsubTopic.get()).valueOr:
+      error "Invalid pubsub topic format", error = error
+      return err(FilterSubscribeError.badRequest("Invalid pubsub topic format"))
+    ok(shard)
+
 proc handleSubscribeRequest*(
     wf: WakuFilter, peerId: PeerId, request: FilterSubscribeRequest
 ): Future[FilterSubscribeResponse] {.async.} =
@@ -141,11 +141,19 @@ proc handleSubscribeRequest*(
     of FilterSubscribeType.SUBSCRIBER_PING:
       subscribeResult = wf.pingSubscriber(peerId)
     of FilterSubscribeType.SUBSCRIBE:
+      let res = getShardFromRequest(request)
       subscribeResult =
-        await wf.subscribe(peerId, request.pubsubTopic, request.contentTopics)
+        if res.isOk():
+          await wf.subscribe(peerId, res.value, request.contentTopics)
+        else:
+          FilterSubscribeResult.err(res.error)
     of FilterSubscribeType.UNSUBSCRIBE:
+      let res = getShardFromRequest(request)
       subscribeResult =
-        wf.unsubscribe(peerId, request.pubsubTopic, request.contentTopics)
+        if res.isOk():
+          wf.unsubscribe(peerId, res.value, request.contentTopics)
+        else:
+          FilterSubscribeResult.err(res.error)
     of FilterSubscribeType.UNSUBSCRIBE_ALL:
       subscribeResult = await wf.unsubscribeAll(peerId)
 
@@ -240,41 +248,37 @@ proc maintainSubscriptions*(wf: WakuFilter) {.async.} =
   waku_filter_subscriptions.set(wf.subscriptions.peersSubscribed.len.float64)
 
 const MessagePushTimeout = 20.seconds
-proc handleMessage*(
-    wf: WakuFilter, pubsubTopic: PubsubTopic, message: WakuMessage
-) {.async.} =
-  let msgHash = computeMessageHash(pubsubTopic, message).to0xHex()
+proc handleMessage*(wf: WakuFilter, shard: RelayShard, message: WakuMessage) {.async.} =
+  let msgHash = computeMessageHash(shard, message).to0xHex()
 
-  debug "handling message", pubsubTopic = pubsubTopic, msg_hash = msgHash
+  debug "handling message", shard = shard, msg_hash = msgHash
 
   let handleMessageStartTime = Moment.now()
 
   block:
     ## Find subscribers and push message to them
     let subscribedPeers =
-      wf.subscriptions.findSubscribedPeers(pubsubTopic, message.contentTopic)
+      wf.subscriptions.findSubscribedPeers(shard, message.contentTopic)
     if subscribedPeers.len == 0:
       error "no subscribed peers found",
-        pubsubTopic = pubsubTopic,
-        contentTopic = message.contentTopic,
-        msg_hash = msgHash
+        shard = shard, contentTopic = message.contentTopic, msg_hash = msgHash
       return
 
-    let messagePush = MessagePush(pubsubTopic: pubsubTopic, wakuMessage: message)
+    let messagePush = MessagePush.init(shard, message)
 
     if not await wf.pushToPeers(subscribedPeers, messagePush).withTimeout(
       MessagePushTimeout
     ):
       error "timed out pushing message to peers",
-        pubsubTopic = pubsubTopic,
+        shard = shard,
         contentTopic = message.contentTopic,
         msg_hash = msgHash,
         numPeers = subscribedPeers.len,
         target_peer_ids = subscribedPeers.mapIt(shortLog(it))
       waku_filter_errors.inc(labelValues = [pushTimeoutFailure])
     else:
-      notice "pushed message succesfully to all subscribers",
-        pubsubTopic = pubsubTopic,
+      notice "pushed message successfully to all subscribers",
+        shard = shard,
         contentTopic = message.contentTopic,
         msg_hash = msgHash,
         numPeers = subscribedPeers.len,
diff --git a/waku/waku_filter_v2/rpc.nim b/waku/waku_filter_v2/rpc.nim
index a81a7bd9a..46e84f27c 100644
--- a/waku/waku_filter_v2/rpc.nim
+++ b/waku/waku_filter_v2/rpc.nim
@@ -28,6 +28,11 @@ type
 
 # Convenience functions
 
+proc init*(
+    T: type MessagePush, shard: RelayShard, wakuMessage: WakuMessage
+): MessagePush =
+  MessagePush(wakuMessage: wakuMessage, pubsubTopic: shard.toPubsubTopic())
+
 proc ping*(T: type FilterSubscribeRequest, requestId: string): T =
   FilterSubscribeRequest(requestId: requestId, filterSubscribeType: SUBSCRIBER_PING)
 
diff --git a/waku/waku_filter_v2/subscriptions.nim b/waku/waku_filter_v2/subscriptions.nim
index 8d3b8084f..d2c465065 100644
--- a/waku/waku_filter_v2/subscriptions.nim
+++ b/waku/waku_filter_v2/subscriptions.nim
@@ -19,8 +19,8 @@ const
   MessageCacheTTL* = 2.minutes
 
 type
-  # a single filter criterion is fully defined by a pubsub topic and content topic
-  FilterCriterion* = tuple[pubsubTopic: PubsubTopic, contentTopic: ContentTopic]
+  # a single filter criterion is fully defined by a shard and content topic
+  FilterCriterion* = tuple[shard: RelayShard, contentTopic: ContentTopic]
 
   FilterCriteria* = HashSet[FilterCriterion] # a sequence of filter criteria
 
@@ -74,9 +74,9 @@ proc getPeerSubscriptions*(
   return subscribedContentTopics
 
 proc findSubscribedPeers*(
-    s: FilterSubscriptions, pubsubTopic: PubsubTopic, contentTopic: ContentTopic
+    s: FilterSubscriptions, shard: RelayShard, contentTopic: ContentTopic
 ): seq[PeerID] =
-  let filterCriterion: FilterCriterion = (pubsubTopic, contentTopic)
+  let filterCriterion: FilterCriterion = (shard, contentTopic)
 
   var foundPeers: seq[PeerID] = @[]
   # only peers subscribed to criteria and with legit subscription is counted