diff --git a/scripts/mk_project.py b/scripts/mk_project.py
index 3eef9e3e8..cb1dae205 100644
--- a/scripts/mk_project.py
+++ b/scripts/mk_project.py
@@ -9,7 +9,7 @@ from mk_util import *
 
 # Z3 Project definition
 def init_project_def():
-    set_version(4, 3, 0, 0)
+    set_version(4, 3, 1, 0)
     add_lib('util', [])
     add_lib('polynomial', ['util'], 'math/polynomial')
     add_lib('sat', ['util'])
diff --git a/src/api/dotnet/Properties/AssemblyInfo.cs b/src/api/dotnet/Properties/AssemblyInfo.cs
index 42e01e793..cdec553fb 100644
--- a/src/api/dotnet/Properties/AssemblyInfo.cs
+++ b/src/api/dotnet/Properties/AssemblyInfo.cs
@@ -34,6 +34,6 @@ using System.Security.Permissions;
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("4.2.0.0")]
-[assembly: AssemblyVersion("4.3.0.0")]
-[assembly: AssemblyFileVersion("4.3.0.0")]
+[assembly: AssemblyVersion("4.3.1.0")]
+[assembly: AssemblyFileVersion("4.3.1.0")]