Unlike modern software that auto-updates via desktop apps, AutoCAD 2009 belongs to the era of manual Service Packs. An "updated" AutoCAD 2009 typically includes three layers:
2009 has no native "Share" or "Trace" features for remote teams.
These fix crashes, plotting errors, DWG save issues, and licensing bugs. You can find them on Autodesk’s FTP/archive sites (search “AutoCAD 2009 SP3”).