diff --git a/src/ol/source/source.js b/src/ol/source/source.js
index 2e4b077a4f..d07f916bdb 100644
--- a/src/ol/source/source.js
+++ b/src/ol/source/source.js
@@ -93,6 +93,19 @@ ol.source.Source.prototype.dispatchChangeEvent = function() {
 };
 
 
+/**
+ * @param {ol.Extent} extent Extent.
+ * @param {number} resolution Resolution.
+ * @param {number} rotation Rotation.
+ * @param {ol.Coordinate} coordinate Coordinate.
+ * @param {function(ol.Feature): T} callback Feature callback.
+ * @return {T|undefined} Callback result.
+ * @template T
+ */
+ol.source.Source.prototype.forEachFeatureAtPixel =
+    goog.nullFunction;
+
+
 /**
  * @return {Array.<ol.Attribution>} Attributions.
  */