diff --git a/pkg/service/v0/data/user.go b/pkg/service/v0/data/user.go
index 015b9a33f..c33d878a9 100644
--- a/pkg/service/v0/data/user.go
+++ b/pkg/service/v0/data/user.go
@@ -8,14 +8,15 @@ type Users struct {
 // User holds the payload for a GetUser response
 type User struct {
 	// TODO needs better naming, clarify if we need a userid, a username or both
-	Enabled     string `json:"enabled" xml:"enabled"`
-	UserID      string `json:"id" xml:"id"`
-	Username    string `json:"username" xml:"username"`
-	DisplayName string `json:"displayname" xml:"displayname"`
-	Email       string `json:"email" xml:"email"`
-	Quota       *Quota `json:"quota" xml:"quota"`
-	UIDNumber   int64  `json:"uidnumber" xml:"uidnumber"`
-	GIDNumber   int64  `json:"gidnumber" xml:"gidnumber"`
+	Enabled           string `json:"enabled" xml:"enabled"`
+	UserID            string `json:"id" xml:"id"`
+	Username          string `json:"username" xml:"username"`
+	DisplayName       string `json:"display-name" xml:"display-name"`
+	LegacyDisplayName string `json:"displayname" xml:"displayname"`
+	Email             string `json:"email" xml:"email"`
+	Quota             *Quota `json:"quota" xml:"quota"`
+	UIDNumber         int64  `json:"uidnumber" xml:"uidnumber"`
+	GIDNumber         int64  `json:"gidnumber" xml:"gidnumber"`
 }
 
 // Quota holds quota information
diff --git a/pkg/service/v0/users.go b/pkg/service/v0/users.go
index eb2fd5ce2..05027fdc8 100644
--- a/pkg/service/v0/users.go
+++ b/pkg/service/v0/users.go
@@ -63,14 +63,16 @@ func (o Ocs) GetUser(w http.ResponseWriter, r *http.Request) {
 	} else {
 		enabled = "false"
 	}
+
 	render.Render(w, r, response.DataRender(&data.User{
-		UserID:      account.Id, // TODO userid vs username! implications for clients if we return the userid here? -> implement graph ASAP?
-		Username:    account.PreferredName,
-		DisplayName: account.DisplayName,
-		Email:       account.Mail,
-		UIDNumber:   account.UidNumber,
-		GIDNumber:   account.GidNumber,
-		Enabled:     enabled,
+		UserID:            account.Id, // TODO userid vs username! implications for clients if we return the userid here? -> implement graph ASAP?
+		Username:          account.PreferredName,
+		DisplayName:       account.DisplayName,
+		LegacyDisplayName: account.DisplayName,
+		Email:             account.Mail,
+		UIDNumber:         account.UidNumber,
+		GIDNumber:         account.GidNumber,
+		Enabled:           enabled,
 		// FIXME onlyfor users/{userid} endpoint (not /user)
 		// TODO query storage registry for free space? of home storage, maybe...
 		Quota: &data.Quota{
@@ -175,13 +177,14 @@ func (o Ocs) AddUser(w http.ResponseWriter, r *http.Request) {
 		enabled = "false"
 	}
 	render.Render(w, r, response.DataRender(&data.User{
-		UserID:      account.Id,
-		Username:    account.PreferredName,
-		DisplayName: account.DisplayName,
-		Email:       account.Mail,
-		UIDNumber:   account.UidNumber,
-		GIDNumber:   account.UidNumber,
-		Enabled:     enabled,
+		UserID:            account.Id,
+		Username:          account.PreferredName,
+		DisplayName:       account.DisplayName,
+		LegacyDisplayName: account.DisplayName,
+		Email:             account.Mail,
+		UIDNumber:         account.UidNumber,
+		GIDNumber:         account.UidNumber,
+		Enabled:           enabled,
 	}))
 }