For users who never "owned" Mavericks on their Apple ID, community-maintained archives are often the only remaining source:
The official way to download is through the Apple App Store, provided you have previously "purchased" (downloaded) it while it was a current release. While the full installer is no longer easily accessible for new users directly from Apple's main servers, various update packages and archives remain available. Official Download Options Mac OS X Mavericks 10.9.5 Free Download
: If you already have an earlier version of Mavericks (10.9.0–10.9.4), you can download the OS X Mavericks 10.9.5 Update (Combo) directly from Apple Support . For users who never "owned" Mavericks on their
: Open the App Store and check the Purchases tab. If you have ever downloaded Mavericks, it will be listed there for free re-download. Third-Party & Alternative Archives : Open the App Store and check the Purchases tab
Before downloading, ensure your Mac is compatible with 10.9.5: Download OS X Mavericks 10.9.5 Update (Combo)
: This platform hosts Apple OS X Mavericks (10.9.5) as a 6.1GB disk image for historical preservation.