Apple today seeded Mavericks 10.9.5 build 13F18 to developers, just under a week after seeding the third OS X 10.9.5 beta, build 13F14, and more than a month after releasing OS X 10.9.4 to the public.
The beta is available through the Software Update mechanism in the Mac App Store and through the Mac Developer Center.
It is unclear what improvements the 10.9.5 update will bring to Mavericks, but it is likely to include bug fixes and stability enhancements. Apple is asking developers to focus on USB, USB Smart Cards, Graphics, Safari, Thunderbolt, and Gatekeeper.
Along with working on improvements to Mavericks, Apple is also beta testing OS X Yosemite, which is due to be released in the fall. The last Mavericks update, 10.9.4, added several Wi-Fi fixes and improved wake from sleep reliability.
Top Rated Comments
I do hope they take their time. As Yosemite official release gets near, that means the Mavericks updates will eventually dwindle down to . nothing.
This is probably the last, or second to the last, Mavericks update, so let's hope Apple makes it a good one.
I won't be touching Yosemite for months after the official release. Mavericks is smooth like butter for me.
You need to sign in with your developer id and be subscribed to the mac developer program.
When you are in, just click on mac development and then os x betas and you will see a whole heap of threads, some of which are about the direct links, but I can't be more specific than that.
Alternatively, you could just use the search facility if you have trouble finding what you want.
http://www.parallels.com/upgradepd10/
There are direct links to the delta and combo update in apple's developer forums. This way you can download the installers and keep them in case you need to reinstall, or if the mac app store isn't working, or install onto several computers without having to redownload each time.
They are only meant for developers, so don't post the links here on macrumors.