With the global launch of Windows 10 less than two weeks away, Microsoft's lawyers and business managers are finishing the pieces of the puzzle that don't involve code.

Earlier this week, Microsoft published its license terms for Windows 10. Today, the company updated its support lifecycle policy for the new OS. In the process, they've cleared up the confusion over a phrase that defines the new Windows 10 servicing model.

Here's the tl;dr:

For Windows 10, Microsoft will continue its traditional 10-year support lifecycle. The five-year mainstream support phase begins with the release of Windows 10 on July 29, 2015, and a second five-year extended support phase begins in 2020 and extends until October 2025. (That's a few months later than July 29, 2025, because of the way Microsoft calculates support dates.)

A note to that policy qualifies the support commitment to devices where the OEM continues to support Windows 10 on that device.

Back in January, Windows boss Terry Myerson announced the new "Windows as a service" plan, using this language:

This is more than a one-time upgrade: once a Windows device is upgraded to Windows 10, we will continue to keep it current for the supported lifetime of the device - at no additional charge.

Today's announcement clears up the "supported lifetime of the device" controversy.

Here's the full text of the footnote:

** Updates are cumulative, with each update built upon all of the updates that preceded it. A device needs to install the latest update to remain supported. Updates may include new features, fixes (security and/or non-security), or a combination of both. Not all features in an update will work on all devices. A device may not be able to receive updates if the device hardware is incompatible, lacking current drivers, or otherwise outside of the Original Equipment Manufacturer's ("OEM") support period. Update availability may vary, for example by country, region, network connectivity, mobile operator (e.g., for cellular-capable devices), or hardware capabilities (including, e.g., free disk space).

There will be no charges for updates during the supported phase. There will be no Windows 10 subscription fees during the supported phase.

If you're concerned about the ramifications of that OEM support clause, you can rest easy, based on what I've heard from insiders with knowledge of the new rules.

You can upgrade to Windows 10 today even on devices where the OEM does not officially support Windows 10 and has no plans to do so. If an OEM sells a device running Windows 10 today and stops delivering driver and firmware updates for it, the device will continue working and it won't stop receiving updates.

It's possible that some new features in a future version of Windows 10 won't work on older devices. In fact, that scenario is already true for the Windows Hello feature, which will only be available at launch on a handful of devices with Intel RealSense cameras. But in those cases the devices will still receive security fixes and other feature updates for which it's eligible.

One question Microsoft didn't answer today is what happens in two or three years. In the past, that would have been time for a new version of Windows to take its place on the support lifecycle chart and bump the old one down a notch. With Windows as a continually evolving platform, that option isn't available.

One clue about what happens next is in that updated support lifecycle page. All other client operating systems are listed by their major version number: Windows 7, Windows 8, and so on. The new entry reads, "Windows 10, released in July 2015."

My guess, based on that language, is that in the next two years or so we'll see an extension of the 10-year lifecycle based on a new baseline release date. But that's just speculation, and we'll have to wait for the actual answer.