diff --git a/doc/api.md b/doc/api.md
index 27b9b3c1b..15807bf9d 100644
--- a/doc/api.md
+++ b/doc/api.md
@@ -165,7 +165,7 @@ parameters defined at device level in database, the parameters are inherit from
 
 ### Uniqueness of groups and devices
 
-Group uniqueness is defined by the combination of: service, subservice, resource and apikey
+Group uniqueness is defined by the combination of: resource and apikey.
 
 Device uniqueness is defined by the combination of: service, subservice, device_id and apikey. Note that several devices
 with the same device_id are allowed in the same service and subservice as long as their apikeys are different.