diff --git a/openrtb-core/src/main/protobuf/openrtb.proto b/openrtb-core/src/main/protobuf/openrtb.proto
index 182198d..a37f423 100644
--- a/openrtb-core/src/main/protobuf/openrtb.proto
+++ b/openrtb-core/src/main/protobuf/openrtb.proto
@@ -1991,17 +1991,15 @@ message BidRequest {
   // apply, it is up to the buyer and seller to coordinate on which floor is
   // applicable.
   message DurFloors {
-    oneof dur_oneof {
-      // An integer indicating the low end of a duration range. If this value is
-      // missing, the low end is unbounded. Either mindur or maxdur is required,
-      // but not both.
-      int32 mindur = 1;
-
-      // An integer indicating the high end of a duration range. If this value
-      // is missing, the high end is unbounded. Either mindur or maxdur is
-      // required, but not both.
-      int32 maxdur = 2;
-    }
+    // An integer indicating the low end of a duration range. If this value is
+    // missing, the low end is unbounded. Either mindur or maxdur is required,
+    // but not both.
+    int32 mindur = 1;
+
+    // An integer indicating the high end of a duration range. If this value is
+    // missing, the high end is unbounded. Either mindur or maxdur is required,
+    // but not both.
+    int32 maxdur = 2;
 
     // Minimum bid for a given impression opportunity, if bidding with a
     // creative in this duration range, expressed in CPM. For any creatives