diff --git a/mmv1/products/tags/TagKey.yaml b/mmv1/products/tags/TagKey.yaml
index c1a94d08e936..9391e856684b 100644
--- a/mmv1/products/tags/TagKey.yaml
+++ b/mmv1/products/tags/TagKey.yaml
@@ -83,11 +83,11 @@ properties:
     description: |
       Input only. The user friendly name for a TagKey. The short name should be unique for TagKeys within the same tag namespace.
 
-      The short name must be 1-63 characters, beginning and ending with an alphanumeric character ([a-z0-9A-Z]) with dashes (-), underscores (_), dots (.), and alphanumerics between.
+      The short name can have a maximum length of 256 characters. The permitted character set for the shortName includes all UTF-8 encoded Unicode characters except single quotes ('), double quotes ("), backslashes (\\), and forward slashes (/).
     required: true
     immutable: true
     validation:
-      function: 'validation.StringLenBetween(1, 63)'
+      function: 'validation.StringLenBetween(1, 256)'
   - name: 'namespacedName'
     type: String
     description: |
diff --git a/mmv1/products/tags/TagValue.yaml b/mmv1/products/tags/TagValue.yaml
index a7e7a8c4594a..fd9d9c38ac41 100644
--- a/mmv1/products/tags/TagValue.yaml
+++ b/mmv1/products/tags/TagValue.yaml
@@ -86,11 +86,11 @@ properties:
     description: |
       Input only. User-assigned short name for TagValue. The short name should be unique for TagValues within the same parent TagKey.
 
-      The short name must be 63 characters or less, beginning and ending with an alphanumeric character ([a-z0-9A-Z]) with dashes (-), underscores (_), dots (.), and alphanumerics between.
+      The short name can have a maximum length of 256 characters. The permitted character set for the shortName includes all UTF-8 encoded Unicode characters except single quotes ('), double quotes ("), backslashes (\\), and forward slashes (/).
     required: true
     immutable: true
     validation:
-      function: 'validation.StringLenBetween(1, 63)'
+      function: 'validation.StringLenBetween(1, 256)'
   - name: 'namespacedName'
     type: String
     description: |