diff --git a/cmd/zrok/reserve.go b/cmd/zrok/reserve.go
index 69e6ecf55..b6be848d0 100644
--- a/cmd/zrok/reserve.go
+++ b/cmd/zrok/reserve.go
@@ -87,6 +87,7 @@ func (cmd *reserveCommand) run(_ *cobra.Command, args []string) {
 	}
 
 	req := &sdk.ShareRequest{
+		Reserved:    true,
 		BackendMode: sdk.BackendMode(cmd.backendMode),
 		ShareMode:   shareMode,
 		BasicAuth:   cmd.basicAuth,
diff --git a/sdk/model.go b/sdk/model.go
index cefb1eb0e..4c27ecd9a 100644
--- a/sdk/model.go
+++ b/sdk/model.go
@@ -20,6 +20,7 @@ const (
 )
 
 type ShareRequest struct {
+	Reserved                        bool
 	BackendMode                     BackendMode
 	ShareMode                       ShareMode
 	Target                          string
diff --git a/sdk/share.go b/sdk/share.go
index 9a1838b86..45feb57fd 100644
--- a/sdk/share.go
+++ b/sdk/share.go
@@ -25,6 +25,7 @@ func CreateShare(root env_core.Root, request *ShareRequest) (*Share, error) {
 	default:
 		return nil, errors.Errorf("unknown share mode '%v'", request.ShareMode)
 	}
+	out.Body.Reserved = request.Reserved
 
 	if len(request.BasicAuth) > 0 {
 		out.Body.AuthScheme = string(Basic)