diff --git a/can-map.js b/can-map.js
index 712263a..89e43a9 100644
--- a/can-map.js
+++ b/can-map.js
@@ -101,10 +101,8 @@ var Map = Construct.extend(
 					if (
 						prop !== "define" &&
 						prop !== "constructor" &&
-						(
-						typeof this.prototype[prop] !== "function" && !canReflect.isValueLike(this.prototype[prop]) ||
-						this.prototype[prop].prototype instanceof Construct
-						)
+						(typeof this.prototype[prop] !== "function" ||
+							this.prototype[prop].prototype instanceof Construct)
 					) {
 						this.defaults[prop] = this.prototype[prop];
 					} else if (canReflect.isObservableLike(this.prototype[prop])) {
diff --git a/can-map_test.js b/can-map_test.js
index b2321fa..95908a0 100644
--- a/can-map_test.js
+++ b/can-map_test.js
@@ -492,3 +492,9 @@ QUnit.test("can.isBound", function(){
 	var p = new Person();
 	QUnit.ok(! p[canSymbol.for("can.isBound")](), "not bound");
 });
+
+QUnit.test("prototype properties", function(assert) {
+	var MyMap = Map.extend({ letters: "ABC" });
+	var map = new MyMap();
+	assert.equal(map.attr("letters"), "ABC");
+});