diff --git a/api/server-server/definitions/pdu_v4.yaml b/api/server-server/definitions/pdu_v4.yaml
index 55b1c26f..a045e657 100644
--- a/api/server-server/definitions/pdu_v4.yaml
+++ b/api/server-server/definitions/pdu_v4.yaml
@@ -13,7 +13,7 @@
 # limitations under the License.
 type: object
 title: Persistent Data Unit
-description: A persistent data unit (event) for room version 3 and beyond.
+description: A persistent data unit (event) for room version 4 and beyond.
 example:
   $ref: "../examples/pdu_v4.json"
 allOf: