diff --git a/src/prebid.js b/src/prebid.js
index c00ff1dd499f..16284115220c 100644
--- a/src/prebid.js
+++ b/src/prebid.js
@@ -155,9 +155,10 @@ $$PREBID_GLOBAL$$.getBidResponsesForAdUnitCode = function (adUnitCode) {
 /**
  * Set query string targeting on one or more GPT ad units.
  * @param {(string|string[])} adUnit a single `adUnit.code` or multiple.
+ * @param {function(object)} customSlotMatching gets a GoogleTag slot and returns a filter function for adUnitCode, so you can decide to match on either eg. return slot => { return adUnitCode => { return slot.getSlotElementId() === 'myFavoriteDivId'; } };
  * @alias module:pbjs.setTargetingForGPTAsync
  */
-$$PREBID_GLOBAL$$.setTargetingForGPTAsync = function (adUnit) {
+$$PREBID_GLOBAL$$.setTargetingForGPTAsync = function (adUnit, customSlotMatching) {
   utils.logInfo('Invoking $$PREBID_GLOBAL$$.setTargetingForGPTAsync', arguments);
   if (!isGptPubadsDefined()) {
     utils.logError('window.googletag is not defined on the page');
@@ -171,7 +172,7 @@ $$PREBID_GLOBAL$$.setTargetingForGPTAsync = function (adUnit) {
   targeting.resetPresetTargeting(adUnit);
 
   // now set new targeting keys
-  targeting.setTargetingForGPT(targetingSet);
+  targeting.setTargetingForGPT(targetingSet, customSlotMatching);
 
   Object.keys(targetingSet).forEach((adUnitCode) => {
     Object.keys(targetingSet[adUnitCode]).forEach((targetingKey) => {
diff --git a/src/targeting.js b/src/targeting.js
index f81949f6d046..e33f1a88f10f 100644
--- a/src/targeting.js
+++ b/src/targeting.js
@@ -160,9 +160,9 @@ export function newTargeting(auctionManager) {
    * Sets targeting for DFP
    * @param {Object.<string,Object.<string,string>>} targetingConfig
    */
-  targeting.setTargetingForGPT = function(targetingConfig) {
+  targeting.setTargetingForGPT = function(targetingConfig, customSlotMatching) {
     window.googletag.pubads().getSlots().forEach(slot => {
-      Object.keys(targetingConfig).filter(isAdUnitCodeMatchingSlot(slot))
+      Object.keys(targetingConfig).filter(customSlotMatching ? customSlotMatching(slot) : isAdUnitCodeMatchingSlot(slot))
         .forEach(targetId =>
           Object.keys(targetingConfig[targetId]).forEach(key => {
             let valueArr = targetingConfig[targetId][key].split(',');