The outfit has published the exFAT technical specification on Microsoft Docs.

For those who came in late, Vole introduced exFAT (Extended File Allocation Table) in November 2006. It’s used in Windows and in many types of storage devices like SD cards and USB flash drives. As file sizes have grown for media content exFAT has become rather important.

But exFAT is proprietary, and Microsoft owns patents on several elements of its design. But Microsoft has been open-sourcing rather a lot lately. It took .NET cross-platform to Mac and Linux in November 2014. The company open-sourced PowerShell and extended it to Linux in August 2016. Microsoft even brought Visual Studio Code to Linux as a Snap in April 2019. Windows Subsystem for Linux (WSL) is a compatibility layer for running Linux binary executables natively on Windows 10 and Windows Server 2009, and WSL 2 is already in the works.

While Microsoft isn’t open-sourcing exFAT it is making sure anyone building with Linux can use it.

A spokesVole said that Microsoft was supporting the addition the exFAT file system to the Linux kernel and the eventual inclusion of a Linux kernel with exFAT support in a future revision of the Open Invention Network’s Linux System Definition.

“We expect that members of the Linux community will be making a code submission for inclusion of an interoperable and conformant version of the exFAT filesystem in the Linux kernel. Once accepted, the code will benefit from the defensive patent commitments of OIN’s 3040+ members and licensees. It’s important to us that the Linux community can make use of exFAT included in the Linux kernel with confidence.”