diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index fd6f87306..00ac5dd86 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -19,8 +19,11 @@ Simple Icons welcomes contributions and corrections. Before contributing, please
 
 We welcome icon requests. Before you submit a new issue please make sure the icon:
 
-* Is of a _popular_ brand.
 * Has not already been requested.
+* Is of a _popular_ brand. For websites, the [Alexa rank](https://www.alexa.com/siteinfo) should be less than 500k. For anything else, popularity will be judged on a case-by-case basis.
+* Isn't related to anything that provides an illegal service (e.g. piracy, malware, threatening material, spam, etc.).
+
+If you are in doubt, feel free to submit it and we'll have a look.
 
 When submitting a request for a new or updated icon include helpful information such as: