diff --git a/src/ng/directive/input.js b/src/ng/directive/input.js
index d14e7f6d6933..6ad762eea193 100644
--- a/src/ng/directive/input.js
+++ b/src/ng/directive/input.js
@@ -1893,7 +1893,12 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     var localValidationRunId = currentValidationRunId;
 
     // We can update the $$invalidModelValue immediately as we don't have to wait for validators!
-    ctrl.$$invalidModelValue = modelValue;
+    if (ctrl.$options && ctrl.$options.allowInvalid) {
+      ctrl.$modelValue = modelValue;
+      doneCallback();
+    } else {
+      ctrl.$$invalidModelValue = modelValue;
+    }
 
     // check parser error
     if (!processParseErrors(parseValid)) {
@@ -1972,9 +1977,10 @@ var NgModelController = ['$scope', '$exceptionHandler', '$attrs', '$element', '$
     function validationDone() {
       if (localValidationRunId === currentValidationRunId) {
         // set the validated model value
-        ctrl.$modelValue = ctrl.$valid ? modelValue : undefined;
-
-        doneCallback();
+        if (!ctrl.$options || !ctrl.$options.allowInvalid) {
+          ctrl.$modelValue = ctrl.$valid ? modelValue : undefined;
+          doneCallback();
+        }
       }
     }
   };
@@ -2751,6 +2757,8 @@ var ngValueDirective = function() {
  *     value of 0 triggers an immediate update. If an object is supplied instead, you can specify a
  *     custom value for each event. For example:
  *     `ng-model-options="{ updateOn: 'default blur', debounce: {'default': 500, 'blur': 0} }"`
+ *   - `allowInvalid`: boolean value which indicates that the model can be set with values that did
+ *     not validate correctly instead of the default behavior of setting the model to undefined.
  *   - `getterSetter`: boolean value which determines whether or not to treat functions bound to
        `ngModel` as getters/setters.
  *   - `timezone`: Defines the timezone to be used to read/write the `Date` instance in the model for
diff --git a/test/ng/directive/inputSpec.js b/test/ng/directive/inputSpec.js
index 8ac1350000aa..3112734ca956 100644
--- a/test/ng/directive/inputSpec.js
+++ b/test/ng/directive/inputSpec.js
@@ -1683,6 +1683,62 @@ describe('input', function() {
           'ng-model-options="{ getterSetter: true }" />');
     });
 
+    it('should assign invalid values to the scope if allowInvalid is true', function() {
+      compileInput('<input type="text" name="input" ng-model="value" maxlength="1" ' +
+                   'ng-model-options="{allowInvalid: true}" />');
+      changeInputValueTo('12345');
+
+      expect(scope.value).toBe('12345');
+      expect(inputElm).toBeInvalid();
+    });
+
+    it('should not assign not parsable values to the scope if allowInvalid is true', function() {
+      compileInput('<input type="number" name="input" ng-model="value" ' +
+                   'ng-model-options="{allowInvalid: true}" />', {
+        valid: false,
+        badInput: true
+      });
+      changeInputValueTo('abcd');
+
+      expect(scope.value).toBeUndefined();
+      expect(inputElm).toBeInvalid();
+    });
+
+    it('should update the scope before async validators execute if allowInvalid is true', inject(function($q) {
+      compileInput('<input type="text" name="input" ng-model="value" ' +
+                   'ng-model-options="{allowInvalid: true}" />');
+      var defer;
+      scope.form.input.$asyncValidators.promiseValidator = function(value) {
+        defer = $q.defer();
+        return defer.promise;
+      };
+      changeInputValueTo('12345');
+
+      expect(scope.value).toBe('12345');
+      expect(scope.form.input.$pending.promiseValidator).toBe(true);
+      defer.reject();
+      scope.$digest();
+      expect(scope.value).toBe('12345');
+      expect(inputElm).toBeInvalid();
+    }));
+
+    it('should update the view before async validators execute if allowInvalid is true', inject(function($q) {
+      compileInput('<input type="text" name="input" ng-model="value" ' +
+                   'ng-model-options="{allowInvalid: true}" />');
+      var defer;
+      scope.form.input.$asyncValidators.promiseValidator = function(value) {
+        defer = $q.defer();
+        return defer.promise;
+      };
+      scope.$apply('value = \'12345\'');
+
+      expect(inputElm.val()).toBe('12345');
+      expect(scope.form.input.$pending.promiseValidator).toBe(true);
+      defer.reject();
+      scope.$digest();
+      expect(inputElm.val()).toBe('12345');
+      expect(inputElm).toBeInvalid();
+    }));
   });
 
   it('should allow complex reference binding', function() {