diff --git a/package.json b/package.json
index 199c470..1d1a48f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@vaadin/vaadin-split-layout",
-  "version": "4.1.1",
+  "version": "4.2.0-alpha1",
   "description": "Polymer element for partitioning a layout into resizeable areas",
   "main": "vaadin-split-layout.html",
   "repository": "vaadin/vaadin-split-layout",
diff --git a/src/vaadin-split-layout.html b/src/vaadin-split-layout.html
index cf6afaa..7660006 100644
--- a/src/vaadin-split-layout.html
+++ b/src/vaadin-split-layout.html
@@ -233,7 +233,7 @@
         }
 
         static get version() {
-          return '4.1.1';
+          return '4.2.0-alpha1';
         }
 
         static get properties() {