diff --git a/spec/lib/sanitize_spec.rb b/spec/lib/sanitize_spec.rb
index 732874a9bef6..b37bcd3e0a93 100644
--- a/spec/lib/sanitize_spec.rb
+++ b/spec/lib/sanitize_spec.rb
@@ -74,6 +74,13 @@
     res.should match(/width/)
   end
   
+  it "should allow negative values" do
+    str = "<div style='margin: -18px;height: 10px;'></div>"
+    res = Sanitize.clean(str, Instructure::SanitizeField::SANITIZE)
+    res.should match(/margin/)
+    res.should match(/height/)
+  end
+
   it "should remove non-whitelisted css attributes" do
     str = "<div style='bacon: 5px; border-left-color: #fff;'></div>"
     res = Sanitize.clean(str, Instructure::SanitizeField::SANITIZE)
diff --git a/vendor/plugins/sanitize_field/lib/sanitize_field.rb b/vendor/plugins/sanitize_field/lib/sanitize_field.rb
index 94c9362c8afc..882a3f555ec6 100644
--- a/vendor/plugins/sanitize_field/lib/sanitize_field.rb
+++ b/vendor/plugins/sanitize_field/lib/sanitize_field.rb
@@ -34,7 +34,7 @@ def self.sanitize_style(env)
       style = node['style'] || ""
       # taken from https://github.com/flavorjones/loofah/blob/master/lib/loofah/html5/scrub.rb
       # the gauntlet
-      style = '' unless style =~ /\A([:,\;#%.\(\)\/\sa-zA-Z0-9!]|\w-\w|\'[\s\w]+\'|\"[\s\w]+\"|\([\d,\s]+\))*\z/
+      style = '' unless style =~ /\A([-:,\;#%.\(\)\/\sa-zA-Z0-9!]|\w-\w|\'[\s\w]+\'|\"[\s\w]+\"|\([\d,\s]+\))*\z/
       style = '' unless style =~ /\A\s*([-\w]+\s*:[^\;]*(\;\s*|$))*\z/
 
       config = env[:config]