diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 6e069df..a2bc3a9 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -16,7 +16,7 @@ Suggested software must also be developer-friendly, which means it meets the fol
 
 (ii) If an open source *library*, it is licensed under one of the open source licenses listed on https://opensource.org/licenses, with the exception of GPL and AGPL (due to their viral nature).  
 
-(iii) If commercial, it has clear pricing.
+(iii) If commercial, it has clear pricing and at least one free tier.
 
 (iv) It has a documentation in the English language.