diff --git a/modules/rubiconBidAdapter.js b/modules/rubiconBidAdapter.js
index 973c6660ece..c4f6e7d545d 100644
--- a/modules/rubiconBidAdapter.js
+++ b/modules/rubiconBidAdapter.js
@@ -532,6 +532,8 @@ export const spec = {
     if (bidRequest?.ortb2Imp?.ext?.ae) {
       data['o_ae'] = 1;
     }
+
+    addDesiredSegtaxes(bidderRequest, data);
     // loop through userIds and add to request
     if (bidRequest.userIdAsEids) {
       bidRequest.userIdAsEids.forEach(eid => {
@@ -1037,6 +1039,27 @@ function applyFPD(bidRequest, mediaType, data) {
   }
 }
 
+function addDesiredSegtaxes(bidderRequest, target) {
+  if (rubiConf.readTopics === false) {
+    return;
+  }
+  let iSegments = [1, 2, 5, 6, 7, 507].concat(rubiConf.sendSiteSegtax?.map(seg => Number(seg)) || []);
+  let vSegments = [4, 508].concat(rubiConf.sendUserSegtax?.map(seg => Number(seg)) || []);
+  let userData = bidderRequest.ortb2?.user?.data || [];
+  let siteData = bidderRequest.ortb2?.site?.content?.data || [];
+  userData.forEach(iterateOverSegmentData(target, 'v', vSegments));
+  siteData.forEach(iterateOverSegmentData(target, 'i', iSegments));
+}
+
+function iterateOverSegmentData(target, char, segments) {
+  return (topic) => {
+    const taxonomy = Number(topic.ext?.segtax);
+    if (segments.includes(taxonomy)) {
+      target[`tg_${char}.tax${taxonomy}`] = topic.segment?.map(seg => seg.id).join(',');
+    }
+  }
+}
+
 /**
  * @param sizes
  * @returns {*}
diff --git a/test/spec/modules/rubiconBidAdapter_spec.js b/test/spec/modules/rubiconBidAdapter_spec.js
index 0312114e75b..184bea07d04 100644
--- a/test/spec/modules/rubiconBidAdapter_spec.js
+++ b/test/spec/modules/rubiconBidAdapter_spec.js
@@ -2770,6 +2770,56 @@ describe('the rubicon adapter', function () {
 
           expect(slotParams['o_ae']).to.equal(1)
         });
+
+        it('should pass along desired segtaxes, but not non-desired ones', () => {
+          const localBidderRequest = Object.assign({}, bidderRequest);
+          localBidderRequest.refererInfo = {domain: 'bob'};
+          config.setConfig({
+            rubicon: {
+              sendUserSegtax: [9],
+              sendSiteSegtax: [10]
+            }
+          });
+          localBidderRequest.ortb2.user = {
+            data: [{
+              ext: {
+                segtax: '404'
+              },
+              segment: [{id: 5}, {id: 6}]
+            }, {
+              ext: {
+                segtax: '508'
+              },
+              segment: [{id: 5}, {id: 2}]
+            }, {
+              ext: {
+                segtax: '9'
+              },
+              segment: [{id: 1}, {id: 2}]
+            }]
+          }
+          localBidderRequest.ortb2.site = {
+            content: {
+              data: [{
+                ext: {
+                  segtax: '10'
+                },
+                segment: [{id: 2}, {id: 3}]
+              }, {
+                ext: {
+                  segtax: '507'
+                },
+                segment: [{id: 3}, {id: 4}]
+              }]
+            }
+          }
+          const slotParams = spec.createSlotParams(bidderRequest.bids[0], localBidderRequest);
+          expect(slotParams['tg_i.tax507']).is.equal('3,4');
+          expect(slotParams['tg_v.tax508']).is.equal('5,2');
+          expect(slotParams['tg_v.tax9']).is.equal('1,2');
+          expect(slotParams['tg_i.tax10']).is.equal('2,3');
+          expect(slotParams['tg_v.tax404']).is.equal(undefined);
+        });
       });
 
       describe('classifiedAsVideo', function () {