diff --git a/increments/OCPS-increment-1.1.md b/increments/OCPS-increment-1.1.md
index d6b92a6..722c4aa 100644
--- a/increments/OCPS-increment-1.1.md
+++ b/increments/OCPS-increment-1.1.md
@@ -29,7 +29,7 @@ An implementation is "OCPS 1.1 Compliant" if it meets all OCPS 1.0 requirements
 
 ### 4.1. Predefined Schedules ("Nicknames")
 
-OCPS 1.1 adds support for case-insensitive nicknames as aliases for common patterns. An implementation MUST recognize the following strings, which MUST NOT be combined with a 5-field expression:
+OCPS 1.1 adds support for nicknames as aliases for common patterns. Nicknames MUST be treated as case-sensitive. An implementation MUST recognize the following strings, which MUST NOT be combined with a 5-field expression:
 
 | Nickname | Equivalent 5-Field Pattern | Description |
 | :--- | :--- | :--- |
diff --git a/increments/OCPS-increment-1.3.md b/increments/OCPS-increment-1.3.md
index 4bfa940..4d17d16 100644
--- a/increments/OCPS-increment-1.3.md
+++ b/increments/OCPS-increment-1.3.md
@@ -27,6 +27,8 @@ An implementation is "OCPS 1.3 Compliant" if it meets all OCPS 1.2 requirements
 
 ## 4\. New Special Characters in OCPS 1.3
 
+The `L` and `W` modifiers defined in this section MUST be treated as case-sensitive.
+
 ### 4.1. `L` (Last) Modifier
 The `L` character can be used in the `Day of Month` and `Day of Week` fields.