diff --git a/src/AnnotationThread.js b/src/AnnotationThread.js
index 2c2f89d3e..060509ebb 100644
--- a/src/AnnotationThread.js
+++ b/src/AnnotationThread.js
@@ -65,10 +65,6 @@ class AnnotationThread extends EventEmitter {
         // Explicitly bind listeners
         this.showDialog = this.showDialog.bind(this);
 
-        if (!this.isMobile) {
-            this.mouseoutHandler = this.mouseoutHandler.bind(this);
-        }
-
         this.setup();
     }
 
@@ -549,26 +545,6 @@ class AnnotationThread extends EventEmitter {
         return indicatorEl;
     }
 
-    /**
-     * Mouseout handler. Hides dialog if we aren't creating the first one.
-     *
-     * @private
-     * @param {HTMLEvent} event - DOM event
-     * @return {void}
-     */
-    mouseoutHandler(event) {
-        if (!event) {
-            return;
-        }
-
-        const mouseInDialog = util.isInDialog(event, event.toElement);
-
-        const firstAnnotation = util.getFirstAnnotation(this.annotations);
-        if (firstAnnotation && !mouseInDialog) {
-            this.hideDialog();
-        }
-    }
-
     /**
      * Saves the provided annotation to the thread and dialog if appropriate
      * and resets state to inactive.
diff --git a/src/__tests__/AnnotationThread-test.js b/src/__tests__/AnnotationThread-test.js
index f89343c92..cd9e1a97b 100644
--- a/src/__tests__/AnnotationThread-test.js
+++ b/src/__tests__/AnnotationThread-test.js
@@ -681,38 +681,6 @@ describe('AnnotationThread', () => {
         });
     });
 
-    // describe('mouseoutHandler()', () => {
-    //     it('should do nothing if event does not exist', () => {
-    //         util.isInDialog = jest.fn();
-    //         thread.mouseoutHandler();
-    //         expect(util.isInDialog).not.toBeCalled();
-    //     });
-
-    //     it('should not call hideDialog if there are no annotations in the thread', () => {
-    //         thread.annotations = [];
-    //         thread.hideDialog = jest.fn();
-    //         thread.mouseoutHandler({});
-    //         expect(thread.hideDialog).not.toBeCalled();
-    //     });
-
-    //     it('should call hideDialog if there are annotations in the thread', () => {
-    //         thread.hideDialog = jest.fn();
-    //         const annotation = new Annotation({
-    //             fileVersionId: '2',
-    //             threadID: '1',
-    //             type: 'point',
-    //             text: 'blah',
-    //             threadNumber: '1',
-    //             location: { x: 0, y: 0 },
-    //             created: Date.now()
-    //         });
-
-    //         thread.annotations = [annotation];
-    //         thread.mouseoutHandler({});
-    //         expect(thread.hideDialog).toBeCalled();
-    //     });
-    // });
-
     describe('saveAnnotationToThread()', () => {
         it('should add the annotation to the thread, and add to the dialog when the dialog exists', () => {
             thread.annotations.push = jest.fn();