diff --git a/event/content.go b/event/content.go
index ec2054b5..2ce9c911 100644
--- a/event/content.go
+++ b/event/content.go
@@ -40,6 +40,9 @@ var TypeMap = map[Type]reflect.Type{
 	StateSpaceParent:       reflect.TypeOf(SpaceParentEventContent{}),
 	StateSpaceChild:        reflect.TypeOf(SpaceChildEventContent{}),
 
+	StateRoomPolicy:         reflect.TypeOf(RoomPolicyEventContent{}),
+	StateUnstableRoomPolicy: reflect.TypeOf(RoomPolicyEventContent{}),
+
 	StateLegacyPolicyRoom:     reflect.TypeOf(ModPolicyContent{}),
 	StateLegacyPolicyServer:   reflect.TypeOf(ModPolicyContent{}),
 	StateLegacyPolicyUser:     reflect.TypeOf(ModPolicyContent{}),
diff --git a/event/state.go b/event/state.go
index 6d027e04..ace170a5 100644
--- a/event/state.go
+++ b/event/state.go
@@ -343,3 +343,15 @@ func (efmc *ElementFunctionalMembersContent) Add(mxid id.UserID) bool {
 	efmc.ServiceMembers = append(efmc.ServiceMembers, mxid)
 	return true
 }
+
+type PolicyServerPublicKeys struct {
+	Ed25519 id.Ed25519 `json:"ed25519,omitempty"`
+}
+
+type RoomPolicyEventContent struct {
+	Via        string                  `json:"via,omitempty"`
+	PublicKeys *PolicyServerPublicKeys `json:"public_keys,omitempty"`
+
+	// Deprecated, only for legacy use
+	PublicKey id.Ed25519 `json:"public_key,omitempty"`
+}
diff --git a/event/type.go b/event/type.go
index 401d7563..3a3e49a2 100644
--- a/event/type.go
+++ b/event/type.go
@@ -113,7 +113,7 @@ func (et *Type) GuessClass() TypeClass {
 		StatePinnedEvents.Type, StateTombstone.Type, StateEncryption.Type, StateBridge.Type, StateHalfShotBridge.Type,
 		StateSpaceParent.Type, StateSpaceChild.Type, StatePolicyRoom.Type, StatePolicyServer.Type, StatePolicyUser.Type,
 		StateElementFunctionalMembers.Type, StateBeeperRoomFeatures.Type, StateBeeperDisappearingTimer.Type,
-		StateMSC4391BotCommand.Type:
+		StateMSC4391BotCommand.Type, StateRoomPolicy.Type, StateUnstableRoomPolicy.Type:
 		return StateEventType
 	case EphemeralEventReceipt.Type, EphemeralEventTyping.Type, EphemeralEventPresence.Type, EphemeralEventAIStream.Type:
 		return EphemeralEventType
@@ -196,6 +196,9 @@ var (
 	StateSpaceChild        = Type{"m.space.child", StateEventType}
 	StateSpaceParent       = Type{"m.space.parent", StateEventType}
 
+	StateRoomPolicy         = Type{"m.room.policy", StateEventType}
+	StateUnstableRoomPolicy = Type{"org.matrix.msc4284.policy", StateEventType}
+
 	StateLegacyPolicyRoom     = Type{"m.room.rule.room", StateEventType}
 	StateLegacyPolicyServer   = Type{"m.room.rule.server", StateEventType}
 	StateLegacyPolicyUser     = Type{"m.room.rule.user", StateEventType}
diff --git a/federation/pdu/pdu.go b/federation/pdu/pdu.go
index cecee5b9..17db6995 100644
--- a/federation/pdu/pdu.go
+++ b/federation/pdu/pdu.go
@@ -123,6 +123,19 @@ func (pdu *PDU) ToClientEvent(roomVersion id.RoomVersion) (*event.Event, error)
 	return evt, nil
 }
 
+func (pdu *PDU) AddSignature(serverName string, keyID id.KeyID, signature string) {
+	if signature == "" {
+		return
+	}
+	if pdu.Signatures == nil {
+		pdu.Signatures = make(map[string]map[id.KeyID]string)
+	}
+	if _, ok := pdu.Signatures[serverName]; !ok {
+		pdu.Signatures[serverName] = make(map[id.KeyID]string)
+	}
+	pdu.Signatures[serverName][keyID] = signature
+}
+
 func marshalCanonical(data any) (jsontext.Value, error) {
 	marshaledBytes, err := json.Marshal(data)
 	if err != nil {
diff --git a/federation/pdu/signature.go b/federation/pdu/signature.go
index a7685cc6..04e7c5ef 100644
--- a/federation/pdu/signature.go
+++ b/federation/pdu/signature.go
@@ -28,13 +28,7 @@ func (pdu *PDU) Sign(roomVersion id.RoomVersion, serverName string, keyID id.Key
 		return fmt.Errorf("failed to marshal redacted PDU to sign: %w", err)
 	}
 	signature := ed25519.Sign(privateKey, rawJSON)
-	if pdu.Signatures == nil {
-		pdu.Signatures = make(map[string]map[id.KeyID]string)
-	}
-	if _, ok := pdu.Signatures[serverName]; !ok {
-		pdu.Signatures[serverName] = make(map[id.KeyID]string)
-	}
-	pdu.Signatures[serverName][keyID] = base64.RawStdEncoding.EncodeToString(signature)
+	pdu.AddSignature(serverName, keyID, base64.RawStdEncoding.EncodeToString(signature))
 	return nil
 }