Previous Release Interoperability
You can open SolidWorks 2013 parts and assemblies using SolidWorks 2012 Service Pack 5.
From SolidWorks 2012 on, you can open a future version file in Service Pack 5 of the previous release. For example, in SolidWorks 2013 Service Pack 5 you will be able to open SolidWorks 2014 files. Interoperability is only supported between consecutive releases. For example, you cannot open a SolidWorks 2014 file in SolidWorks 2012 Service Pack 5.
Future version files appear in read-only mode when opened in the previous release. However, once you upgrade to the next version of SolidWorks, all the FeatureManager
design tree data is available. SolidWorks 2013 files have reduced functionality in SolidWorks 2012 Service Pack 5. SolidWorks 2013 files will not have most FeatureManager design tree data when opened in SolidWorks 2012 Service Pack 5. Any actions that require FeatureManager design tree data cannot be performed with a SolidWorks 2013 document open in SolidWorks 2012 Service Pack 5.
The following table summarizes what you can and cannot do in SolidWorks 2012 Service Pack 5: