diff --git a/app/assets/javascripts/darkswarm/directives/validate_stock_quantity.js.coffee b/app/assets/javascripts/darkswarm/directives/validate_stock_quantity.js.coffee
new file mode 100644
index 0000000000..404a9759e1
--- /dev/null
+++ b/app/assets/javascripts/darkswarm/directives/validate_stock_quantity.js.coffee
@@ -0,0 +1,17 @@
+Darkswarm.directive "validateStockQuantity", ->
+  restrict: 'A'
+  require: "ngModel"
+
+  link: (scope, element, attr, ngModel) ->
+    ngModel.$parsers.push (selectedQuantity) ->
+      if parseInt(selectedQuantity) > scope.available_quantity()
+        ngModel.$setValidity('stock', false);
+      else
+        ngModel.$setValidity('stock', true);
+
+      selectedQuantity
+
+    scope.available_quantity = ->
+      on_hand = parseInt(attr.ofnOnHand)
+      finalized_quantity = parseInt(attr.finalizedquantity) || 0 # finalizedquantity is optional
+      on_hand + finalized_quantity
diff --git a/app/assets/stylesheets/darkswarm/shopping-cart.css.scss b/app/assets/stylesheets/darkswarm/shopping-cart.css.scss
index 3423102b72..a20897fe2b 100644
--- a/app/assets/stylesheets/darkswarm/shopping-cart.css.scss
+++ b/app/assets/stylesheets/darkswarm/shopping-cart.css.scss
@@ -103,7 +103,7 @@
     }
   }
 
-  input.warning {
+  input.ng-invalid-stock {
     border: 1px solid $clr-brick;
   }
 }
diff --git a/app/views/spree/orders/_line_item.html.haml b/app/views/spree/orders/_line_item.html.haml
index 5aab298b51..918a520fdf 100644
--- a/app/views/spree/orders/_line_item.html.haml
+++ b/app/views/spree/orders/_line_item.html.haml
@@ -27,7 +27,7 @@
       :min => 0, "ofn-on-hand" => "#{variant.on_demand && 9999 || variant.on_hand}",
       "finalizedquantity" => finalized_quantity, :class => "line_item_quantity", :size => 5,
       "ng-model" => "line_item_#{line_item.id}",
-      "ng-class" => "{ warning: #{@insufficient_stock_lines.andand.include? line_item} }"
+      "validate-stock-quantity" => true
   %td.cart-item-total.text-right{"data-hook" => "cart_item_total"}
     = line_item.display_amount_with_adjustments.to_html unless line_item.quantity.nil?