diff --git a/staging/src/k8s.io/api/networking/v1alpha1/types.go b/staging/src/k8s.io/api/networking/v1alpha1/types.go
index bcdc33b4599..0e454f02635 100644
--- a/staging/src/k8s.io/api/networking/v1alpha1/types.go
+++ b/staging/src/k8s.io/api/networking/v1alpha1/types.go
@@ -109,6 +109,9 @@ type ServiceCIDR struct {
 type ServiceCIDRSpec struct {
 	// CIDRs defines the IP blocks in CIDR notation (e.g. "192.168.0.0/24" or "2001:db8::/64")
 	// from which to assign service cluster IPs. Max of two CIDRs is allowed, one of each IP family.
+	// The network address of each CIDR, the address that identifies the subnet of a host, is reserved
+	// and will not be allocated. The broadcast address for IPv4 CIDRs is also reserved and will not be
+	// allocated.
 	// This field is immutable.
 	// +optional
 	// +listType=atomic