diff --git a/include/ircd/m/dbs.h b/include/ircd/m/dbs.h
index ecef256ab..4cec9dbff 100644
--- a/include/ircd/m/dbs.h
+++ b/include/ircd/m/dbs.h
@@ -35,6 +35,8 @@ namespace ircd::m::dbs
 	std::tuple<string_view, string_view> room_state_key(const string_view &amalgam);
 
 	string_view room_origins_key(const mutable_buffer &out, const id::room &, const string_view &origin, const id::user &member);
+	std::tuple<string_view, string_view> room_origins_key(const string_view &amalgam);
+
 	string_view room_events_key(const mutable_buffer &out, const id::room &, const uint64_t &depth, const id::event &);
 	string_view room_events_key(const mutable_buffer &out, const id::room &, const uint64_t &depth);
 	std::tuple<uint64_t, string_view> room_events_key(const string_view &amalgam);
@@ -85,9 +87,11 @@ namespace ircd::m::dbs::desc
 
 	// Metadata columns
 	extern const database::descriptor events__state_node;
+
 	extern const db::prefix_transform events__room_events__pfx;
 	extern const db::comparator events__room_events__cmp;
 	extern const database::descriptor events__room_events;
+
 	extern const db::prefix_transform events__room_origins__pfx;
 	extern const database::descriptor events__room_origins;
 
diff --git a/ircd/m/dbs.cc b/ircd/m/dbs.cc
index e7b19c27d..bb3f30cd0 100644
--- a/ircd/m/dbs.cc
+++ b/ircd/m/dbs.cc
@@ -648,6 +648,10 @@ ircd::m::dbs::desc::events__room_events
 	events__room_events__pfx,
 };
 
+//
+// origins sequential
+//
+
 /// Prefix transform for the events__room_origins
 ///
 /// TODO: This needs The Grammar
@@ -684,6 +688,26 @@ ircd::m::dbs::room_origins_key(const mutable_buffer &out,
 	return { data(out), len };
 }
 
+std::tuple<ircd::string_view, ircd::string_view>
+ircd::m::dbs::room_origins_key(const string_view &amalgam)
+{
+	const auto &key
+	{
+		lstrip(amalgam, ":::")
+	};
+
+	const auto &s
+	{
+		split(key, "@")
+	};
+
+	return
+	{
+		{ s.first },
+		{ end(s.first), end(key) }
+	};
+}
+
 const ircd::database::descriptor
 ircd::m::dbs::desc::events__room_origins
 {
diff --git a/ircd/m/room.cc b/ircd/m/room.cc
index cec711fbd..a8d8f5c18 100644
--- a/ircd/m/room.cc
+++ b/ircd/m/room.cc
@@ -638,7 +638,7 @@ const
 		{
 			const string_view &member
 			{
-				end(split(key, "@").first), end(key)
+				std::get<1>(dbs::room_origins_key(key))
 			};
 
 			bool ret{false};
@@ -745,9 +745,9 @@ const
 	return _test_([&last, &lastbuf, &view]
 	(const string_view &key)
 	{
-		const string_view &origin //TODO: XXX
+		const string_view &origin
 		{
-			split(key, "@").first
+			std::get<0>(dbs::room_origins_key(key))
 		};
 
 		if(origin == last)