Apple today seeded build 13D17 of OS X 10.9.3 to developers, one week after releasing the first OS X 10.9.3 beta, build 13D12



From MacRumors:

The beta is available through the Software Update mechanism in the Mac App Store as well as through the Mac Dev Center. Apple is currently asking developers to focus on Graphics Drivers and Audio. As was discovered last week, 10.9.3 adds new support for 4K displays, offering "Retina" resolutions that improve readability.

  Apple Seeds OS X Mavericks 10.9.3 Build 13D17 to Developer