diff --git a/README.md b/README.md
index d0404945e039e0b94bf850d9727843a839455939..0bb9796fa77d1445779079fd1efe1e0a9cb1ba58 100644
--- a/README.md
+++ b/README.md
@@ -42,6 +42,8 @@ Suggestions in the form of **Issues** and contributions in the form of **Pull Re
     cd decentraleyes
     jpm xpi
 
+> **Important:** All commits since 26 October 2016 are signed with GPG. It's likely best to ignore unsigned commits, unless you really know what you're doing. Please send an email if you have any questions or security concerns.
+
 ## License
 
 [MPL-2.0](https://www.mozilla.org/MPL/2.0).