diff --git a/externs/olx.js b/externs/olx.js
index a6b0c889f5..64615ed687 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -2837,7 +2837,8 @@ olx.interaction.KeyboardZoomOptions.prototype.delta;
 
 
 /**
- * @typedef {{deleteCondition: (ol.events.ConditionType|undefined),
+ * @typedef {{condition: (ol.events.ConditionType|undefined),
+ *     deleteCondition: (ol.events.ConditionType|undefined),
  *     pixelTolerance: (number|undefined),
  *     style: (ol.style.Style|Array.<ol.style.Style>|ol.style.StyleFunction|undefined),
  *     features: ol.Collection.<ol.Feature>,
@@ -2847,6 +2848,17 @@ olx.interaction.KeyboardZoomOptions.prototype.delta;
 olx.interaction.ModifyOptions;
 
 
+/**
+ * A function that takes an {@link ol.MapBrowserEvent} and returns a boolean
+ * to indicate whether that event will be considered to add or move a vertex
+ * to the sketch.
+ * Default is {@link ol.events.condition.primaryAction}.
+ * @type {ol.events.ConditionType|undefined}
+ * @api
+ */
+olx.interaction.ModifyOptions.prototype.condition;
+
+
 /**
  * A function that takes an {@link ol.MapBrowserEvent} and returns a boolean
  * to indicate whether that event should be handled.
diff --git a/src/ol/events/condition.js b/src/ol/events/condition.js
index 1d0662b40c..9ef1f0075a 100644
--- a/src/ol/events/condition.js
+++ b/src/ol/events/condition.js
@@ -220,3 +220,18 @@ ol.events.condition.mouseOnly = function(mapBrowserEvent) {
   // see http://www.w3.org/TR/pointerevents/#widl-PointerEvent-pointerType
   return mapBrowserEvent.pointerEvent.pointerType == 'mouse';
 };
+
+
+/**
+ * Return `true` if the event originates from a primary pointer in
+ * contact with the surface or if the left mouse button is pressed.
+ * @see http://www.w3.org/TR/pointerevents/#button-states
+ *
+ * @param {ol.MapBrowserEvent} mapBrowserEvent Map browser event.
+ * @return {boolean} True if the event originates from a primary pointer.
+ * @api
+ */
+ol.events.condition.primaryAction = function(mapBrowserEvent) {
+  var pointerEvent = mapBrowserEvent.pointerEvent;
+  return pointerEvent.isPrimary && pointerEvent.button === 0;
+};
diff --git a/src/ol/interaction/modifyinteraction.js b/src/ol/interaction/modifyinteraction.js
index 1d931f9849..e88fbc0d2f 100644
--- a/src/ol/interaction/modifyinteraction.js
+++ b/src/ol/interaction/modifyinteraction.js
@@ -112,6 +112,14 @@ ol.interaction.Modify = function(options) {
     handleUpEvent: ol.interaction.Modify.handleUpEvent_
   });
 
+  /**
+   * @private
+   * @type {ol.events.ConditionType}
+   */
+  this.condition_ = options.condition ?
+      options.condition : ol.events.condition.primaryAction;
+
+
   /**
    * @private
    * @param {ol.MapBrowserEvent} mapBrowserEvent Browser event.
@@ -553,6 +561,9 @@ ol.interaction.Modify.compareIndexes_ = function(a, b) {
  * @private
  */
 ol.interaction.Modify.handleDownEvent_ = function(evt) {
+  if (!this.condition_(evt)) {
+    return false;
+  }
   this.handlePointerAtPixel_(evt.pixel, evt.map);
   this.dragSegments_.length = 0;
   this.modified_ = false;
diff --git a/test/spec/ol/interaction/modifyinteraction.test.js b/test/spec/ol/interaction/modifyinteraction.test.js
index 970e9358af..eb3a7c46a1 100644
--- a/test/spec/ol/interaction/modifyinteraction.test.js
+++ b/test/spec/ol/interaction/modifyinteraction.test.js
@@ -68,10 +68,12 @@ describe('ol.interaction.Modify', function() {
     var shiftKey = opt_shiftKey !== undefined ? opt_shiftKey : false;
     var pointerEvent = new ol.pointer.PointerEvent(type, {
       type: type,
-      button: button,
       clientX: position.left + x + width / 2,
       clientY: position.top + y + height / 2,
       shiftKey: shiftKey
+    }, {
+      button: button,
+      isPrimary: true
     });
     var event = new ol.MapBrowserPointerEvent(type, map, pointerEvent);
     event.pointerEvent.pointerId = 1;
@@ -376,6 +378,23 @@ describe('ol.interaction.Modify', function() {
 
       validateEvents(events, [feature]);
     });
+
+    it('clicking with right button should not add a vertex', function() {
+      expect(feature.getGeometry().getRevision()).to.equal(1);
+      expect(feature.getGeometry().getCoordinates()[0]).to.have.length(5);
+
+      simulateEvent('pointermove', 40, -20, false, 0);
+      // right click
+      simulateEvent('pointerdown', 40, -20, false, 1);
+      simulateEvent('pointermove', 30, -20, false, 1);
+      simulateEvent('pointerdrag', 30, -20, false, 1);
+      simulateEvent('pointerup', 30, -20, false, 1);
+
+      expect(feature.getGeometry().getRevision()).to.equal(1);
+      expect(feature.getGeometry().getCoordinates()[0]).to.have.length(5);
+      expect(events).to.have.length(0);
+    });
+
   });
 
   describe('double click deleteCondition', function() {