diff --git a/api/api-rules/sample_apiserver_violation_exceptions.list b/api/api-rules/sample_apiserver_violation_exceptions.list
index 79c8866ad2a..8f1c9408a63 100644
--- a/api/api-rules/sample_apiserver_violation_exceptions.list
+++ b/api/api-rules/sample_apiserver_violation_exceptions.list
@@ -1,4 +1,3 @@
-API rule violation: list_type_missing,k8s.io/sample-apiserver/pkg/apis/wardle/v1alpha1,Fischer,DisallowedFlunders
 API rule violation: names_match,k8s.io/apimachinery/pkg/apis/meta/v1,APIResourceList,APIResources
 API rule violation: names_match,k8s.io/apimachinery/pkg/apis/meta/v1,Duration,Duration
 API rule violation: names_match,k8s.io/apimachinery/pkg/apis/meta/v1,InternalEvent,Object
diff --git a/staging/src/k8s.io/sample-apiserver/pkg/apis/wardle/v1alpha1/types.go b/staging/src/k8s.io/sample-apiserver/pkg/apis/wardle/v1alpha1/types.go
index 3332e7c1ec1..39079e4a8d9 100644
--- a/staging/src/k8s.io/sample-apiserver/pkg/apis/wardle/v1alpha1/types.go
+++ b/staging/src/k8s.io/sample-apiserver/pkg/apis/wardle/v1alpha1/types.go
@@ -65,6 +65,7 @@ type Fischer struct {
 	metav1.ObjectMeta `json:"metadata,omitempty" protobuf:"bytes,1,opt,name=metadata"`
 
 	// DisallowedFlunders holds a list of Flunder.Names that are disallowed.
+	// +listType=atomic
 	DisallowedFlunders []string `json:"disallowedFlunders,omitempty" protobuf:"bytes,2,rep,name=disallowedFlunders"`
 }
 
diff --git a/staging/src/k8s.io/sample-apiserver/pkg/generated/openapi/zz_generated.openapi.go b/staging/src/k8s.io/sample-apiserver/pkg/generated/openapi/zz_generated.openapi.go
index c2c5d79515b..98fad74f017 100644
--- a/staging/src/k8s.io/sample-apiserver/pkg/generated/openapi/zz_generated.openapi.go
+++ b/staging/src/k8s.io/sample-apiserver/pkg/generated/openapi/zz_generated.openapi.go
@@ -2662,6 +2662,11 @@ func schema_pkg_apis_wardle_v1alpha1_Fischer(ref common.ReferenceCallback) commo
 						},
 					},
 					"disallowedFlunders": {
+						VendorExtensible: spec.VendorExtensible{
+							Extensions: spec.Extensions{
+								"x-kubernetes-list-type": "atomic",
+							},
+						},
 						SchemaProps: spec.SchemaProps{
 							Description: "DisallowedFlunders holds a list of Flunder.Names that are disallowed.",
 							Type:        []string{"array"},