diff --git a/lib/jsdoc/name.js b/lib/jsdoc/name.js
index a16ee02c..7aa0c1c2 100644
--- a/lib/jsdoc/name.js
+++ b/lib/jsdoc/name.js
@@ -217,6 +217,11 @@ exports.hasAncestor = function(parent, child) {
         return hasAncestor;
     }
 
+    // fast path for obvious non-ancestors
+    if (child.indexOf(parent) !== 0) {
+        return hasAncestor;
+    }
+
     do {
         memberof = exports.shorten(memberof).memberof;
 
diff --git a/test/specs/jsdoc/name.js b/test/specs/jsdoc/name.js
index 8805f089..0b034f0f 100644
--- a/test/specs/jsdoc/name.js
+++ b/test/specs/jsdoc/name.js
@@ -293,6 +293,12 @@ describe('jsdoc/name', function() {
             expect(hasAncestor).toBe(true);
         });
 
+        it('should correctly identify when a non-ancestor is passed in', function() {
+            var hasAncestor = jsdoc.name.hasAncestor('module:foo', 'foo');
+
+            expect(hasAncestor).toBe(false);
+        });
+
         it('should not say that a longname is its own ancestor', function() {
             var hasAncestor = jsdoc.name.hasAncestor('module:foo', 'module:foo');