diff --git a/SPEC.md b/SPEC.md
index 9436c892..d26c3ea9 100644
--- a/SPEC.md
+++ b/SPEC.md
@@ -523,6 +523,7 @@ For certain operations, plugins must output result information. The output shoul
 ### ADD Success
 
 Plugins must output a JSON object with the following keys upon a successful `ADD` operation:
+All keys are optional other than `cniVersion`.
 
 - `cniVersion`: The same version supplied on input - the string "1.1.0"
 - `interfaces`: An array of all interfaces created by the attachment, including any host-level interfaces:
diff --git a/pkg/types/100/types.go b/pkg/types/100/types.go
index 6c138568..beb46b07 100644
--- a/pkg/types/100/types.go
+++ b/pkg/types/100/types.go
@@ -92,7 +92,7 @@ type Result struct {
 	Interfaces []*Interface   `json:"interfaces,omitempty"`
 	IPs        []*IPConfig    `json:"ips,omitempty"`
 	Routes     []*types.Route `json:"routes,omitempty"`
-	DNS        types.DNS      `json:"dns,omitempty"`
+	DNS        *types.DNS     `json:"dns,omitempty"`
 }
 
 // convertFrom100 does nothing except set the version; the types are the same
@@ -145,7 +145,7 @@ func convertFrom04x(from types.Result, toVersion string) (types.Result, error) {
 	fromResult := from.(*types040.Result)
 	toResult := &Result{
 		CNIVersion: toVersion,
-		DNS:        *fromResult.DNS.Copy(),
+		DNS:        fromResult.DNS.Copy(),
 		Routes:     []*types.Route{},
 	}
 	for _, fromIntf := range fromResult.Interfaces {
diff --git a/pkg/types/types.go b/pkg/types/types.go
index 780dfa13..b4f8c1bb 100644
--- a/pkg/types/types.go
+++ b/pkg/types/types.go
@@ -64,7 +64,7 @@ type NetConf struct {
 	Type         string          `json:"type,omitempty"`
 	Capabilities map[string]bool `json:"capabilities,omitempty"`
 	IPAM         IPAM            `json:"ipam,omitempty"`
-	DNS          DNS             `json:"dns,omitempty"`
+	DNS          *DNS            `json:"dns,omitempty"`
 
 	RawPrevResult map[string]interface{} `json:"prevResult,omitempty"`
 	PrevResult    Result                 `json:"-"`