diff --git a/src/SOL005/definitions/SOL005_def.yaml b/src/SOL005/definitions/SOL005_def.yaml
index 29fb9e1a492efc7e67a1d669e3e2fc252a14a039..b5709eb0fe20e96a84990bb83cee13671d4b351e 100644
--- a/src/SOL005/definitions/SOL005_def.yaml
+++ b/src/SOL005/definitions/SOL005_def.yaml
@@ -278,13 +278,14 @@ definitions:
         type: array
         items:
           type: object
+          required:
+            - version
           properties:
             version:
               description: >
                 Identifies a supported version. The value of the version attribute shall
                 be a version identifier as specified in clause 4.6.1.
               type: string
-              required: true
             isDeprecated:
               description: >
                 If such information is available, this attribute indicates whether use of the
@@ -293,14 +294,12 @@ definitions:
                 not to be used any longer. When a version is no longer supported, it does not
                 appear in the response body.
               $ref: "#/definitions/Boolean"
-              required: false
             retirementDate:
               description: >
                 The date and time after which the API version will no longer be supported.
                 This attribute may be included if the value of the isDeprecated attribute
                 is set to true and shall be absent otherwise.
               $ref: "#/definitions/DateTime"
-              required: false
 
   SubscriptionAuthentication:
     type: object