Android gains its first SDXC flash driver safe from Microsoft patent threats

Tuxera offers Android/Linux driver for next-generation memory flash cards that relies on Microsoft's exFAT

Good news for anyone that uses an Android (or Linux) cell phone, mobile device or PC. Tuxera has released its long-awaited specification that makes the new SDXC memory cards compatible with Android or other Linux flavors.

SDXC includes at its heart Microsoft's exFAT specification, a big win for Microsoft because every device manufacturer that wants to create SDXC cards -- or build technology that taps into them -- has to pay Microsoft royalties. The TomTom/Microsoft case was, at its heart, about the issue of file

technologies royalties (not as much about Microsoft hammering on Linux -- though that was a bonus for Microsoft). TomTom used a file system that Microsoft owned with patent claims, and Microsoft filed a rare patent infringement case to protect its file system turf. (Microsoft is typically the victim of patent infringement suits, not the perpetrator).

While TomTom's problems were about Microsoft's previous FAT technology, not exFAT, SDXC was hung under the same cloud. Indeed, Microsoft already announced a similar licensing agreement with Panasonic for exFAT, and the older technology FAT LFN, to cover its use of them in flash-enabled devices.

About a year ago, Tuxera stepped up to the plate to negotiate with Microsoft to create an SDXC specification for Android/Linux, and today that driver arrived. This means that users of those operating systems can swap the latest memory cards from their cameras, music players and whatnot, and stick them into their Android PCs, phones or tablets and so on. Tuxera already had a good relationship with Microsoft, so it was perhaps a natural fit that it be the one to step up and do this for Android/Linux device makers.

Now, it may pain the Linux development community to know that because the standard uses exFAT, Microsoft makes royalties on every SDXC device made. This is certainly contrary to the free software movement's way, but it is how business has been done in the computer industry for decades. Standards bodies have a doctrine called Reasonable and Non Discriminatory Licensing (RAND). Technology companies eagerly participate in standards bodies and contribute their proprietary technology to the standard, if they, in exchange, agree to RAND. They must license the use of that technology to anyone that wants it to implement the standard. (Interoperability is the point of standards, after all.) And the company must agree to license the technology at an extremely low cost to all commers -- say, for example, a few pennies per device. It adds up to a pretty penny for the technology owner, in this case, Microsoft.

So it is with exFat, Microsoft and SDXC.

Tuxera's CEO, Mikko Valimaki, who answered a few questions via e-mail from me. He wouldn't divulge how much his company paid to Microsoft to create an exFAT SDXC-compatible plan for Android, nor tell me how much hardware makers will be required to pay Microsoft, or even Tuxera. Here's the gist:

Me: Did Tuxera license exFAT from Microsoft?

Mikko Valimaki: Yes. In summer of 2009, after one year of discussions. The agreement covers access to the exFAT specifications, Microsoft’s source code implementation of exFAT, and testing and verification tools. Here is the announcement.

Me: Your announcement says that Tuxera’s exFAT system supports SDXC … do users of SDXC in general and Tuxera’s SDXC in particularly have to pay Microsoft a licensing fee? 

Mikko Valimaki: SDXC is the SD card standard, while exFAT is the file system within that standard. Tuxera exFAT, in turn, is an exFAT file system implementation that enables devices to interface with SDXC cards. Manufacturers that use the Tuxera exFAT system in mobile phones, digital cameras, and other devices require both an exFAT patent agreement from Microsoft and a licensing agreement from Tuxera.

In a few years there will be billions of SDXC cards all over the world; all using the exFAT file system. No option. This is the standard. Most embedded devices use Linux (Google's Android, Intel's and Nokia's MeeGo, Samsung's Bada, etc.). Linux adoption is growing, taking market share from most of the proprietary operating systems. Basically, Tuxera has assumed a leadership role, through work with Microsoft and the SD Association, in handling billions of consumer electronics devices that will be using SDXC cards in the coming years. Tuxera exFAT for Android and other Linux systems was a major first.

Me: Can you comment on what that fee is? (Typically, patented technology included in a standard has a low fee … a few pennies per implementation to a few dollars …)

MV: Microsoft offers a flexible Intellectual Property (IP) licensing program for their exFAT file system. Please ask Microsoft for details.

Here's the Tuxera's press release in full, which offers a few more details (and a lot more congratulatory speech) on the Android exFAT driver.

Tuxera exFAT Now Available for Android and Linux

First exFAT solution for embedded Linux based on Microsoft documentation

Taipei, Taiwan [COMPUTEX] - June 1, 2010 - Tuxera, the leading designer of Windows-compatible file systems for Linux, Mac, and other platforms, today announced the release of Tuxera exFAT for Android and other Linux systems. Developed using technical documentation provided by Microsoft Corp., Tuxera exFAT provides outstanding performance and stability, and meets the latest SDXC memory card standards.

"The wait is over. I am thrilled to tell everyone we now have the world's first exFAT implementation for Android. Thanks to our latest innovations and strong relationship with Microsoft, we can guarantee blazingly fast performance for flash drives and energy efficient consumer electronics," said Mikko Välimäki, Tuxera CEO. "Tuxera's exFAT for Android is not just the first to market, but it is also built on a very portable codebase that we will strive to make the de facto standard."

Tuxera is now forming partnerships with leading hardware, device, and operating system manufacturers to meet the growing demand for high-definition video and other embedded applications.

"exFAT is a modern file system designed to handle very large files, and we are pleased to support Tuxera's development of an exFAT file system implementation," said David Kaefer, general manager of Intellectual Property Licensing at Microsoft. "To provide necessary patent rights, Microsoft will offer a patent agreement that companies can sign if they are building a device that includes the Tuxera exFAT implementation."

Tuxera is a member of the SD Association where it works together with exFAT host device and card manufacturers to enable a smooth transition from FAT to exFAT file system technology that lifts the device and file size limits for SD cards. For example, with Tuxera exFAT new SDXC compatible devices can record normal-length, full-HD videos.

Tuxera exFAT has been successfully tested on Android and other versions of Linux. To request an evaluation version of the product, please contact  A consumer download version will be released later.

About Tuxera.

Tuxera is the leading designer of file systems that allow music, pictures, videos and other content to be ported across devices. With Tuxera file systems inside, users experience plug and play interoperability with their laptops, digital cameras, set-top-boxes, mobile phones, and other consumer electronics.

Building on the success of open source, Tuxera's industry-standard NTFS and exFAT solutions for Linux, Mac OS X, and other platforms have over 30 million installations. Close collaboration with Microsoft ensures reliable compatibility and helps Tuxera to set the standard in high-performance, low power use for embedded and mobile solutions. Tuxera's customers include leading hardware, software, and consumer electronics companies. For more info, please go to

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