diff --git a/modules/distroscaleBidAdapter.js b/modules/distroscaleBidAdapter.js
index 005dd3e67d6..7a2038ed3f0 100644
--- a/modules/distroscaleBidAdapter.js
+++ b/modules/distroscaleBidAdapter.js
@@ -132,6 +132,24 @@ export const spec = {
     // TODO: does the fallback to window.location make sense?
     var pageUrl = bidderRequest?.refererInfo?.page || window.location.href;
 
+    // check if dstag is already loaded in ancestry tree
+    var dsloaded = 0;
+    try {
+      var win = window;
+      while (true) {
+        if (win.vx.cs_loaded) {
+          dsloaded = 1;
+        }
+        if (win != win.parent) {
+          win = win.parent;
+        } else {
+          break;
+        }
+      }
+    } catch (error) {
+      // ignore exception
+    }
+
     var payload = {
       id: '' + (new Date()).getTime(),
       at: AUCTION_TYPE,
@@ -149,7 +167,9 @@ export const spec = {
       },
       imp: [],
       user: {},
-      ext: {}
+      ext: {
+        dsloaded: dsloaded
+      }
     };
 
     validBidRequests.forEach(b => {