Microsoft Office Proofing Tools 2013 Service Pack 1 (SP1) provides the latest updates for Office Proofing Tools 2013. This service pack includes two kinds of fixes:
Previously unreleased fixes that are included in this service pack. In addition to general product fixes, these fixes include improvements in stability, performance, and security.
All the monthly security updates that were released through January 2014, and all the Cumulative Updates that were released through December 2013.