diff --git a/.github/CONTRIBUTING.md b/.github/CONTRIBUTING.md
index 9134da614d78..5428d9ba466c 100644
--- a/.github/CONTRIBUTING.md
+++ b/.github/CONTRIBUTING.md
@@ -99,6 +99,9 @@ The use of the : operator to override type safety checks is not allowed. You mus
 ### Type paths must begin with a /
 eg: `/datum/thing`, not `datum/thing`
 
+### Type paths must be lowercase
+eg: `/datum/thing/blue`, not `datum/thing/BLUE` or `datum/thing/Blue`
+
 ### Datum type paths must began with "datum"
 In DM, this is optional, but omitting it makes finding definitions harder.