Autodesk released AutoCAD Civil 3D 2012 Service Pack 3 on Jun 4, 2013
Jun 4, 2013 - Autodesk released AutoCAD Civil 3D 2012 Service Pack 3. SP3 fixes or addresses a variety of issues discovered by customers and by Autodesk's internal testing team.
This service pack does not include previous Hotfixes or Service Packs for AutoCAD Civil 3D 2012. In order to install AutoCAD Civil 3D 2012 Service Pack 3 you must have already applied AutoCAD Civil 3D 2012 Service Pack 2 or Service Pack 2.1.