Details of a deal between Microsoft and Nvidia which gives the software giant first refusal should the graphics specialist come up for sale have emerged - but why does the deal still exist?
The first clue as to the existence of the deal was spotted last week by the guys over at InformationWeek in an SEC filing from Nvidia, in which the company stated that "Microsoft may have first and last rights of refusal to purchase the stock... if an individual or corporation makes an offer to purchase shares equal to or greater than 30 per cent of the outstanding shares of our common stock."
In summary, the deal means that anyone wanting to buy a substantial chunk of the graphics specialist would need to submit an offer and wait for Microsoft to decide if it wanted to call its bluff. If Microsoft wanted, it could gazzump the offer and buy the Nvidia shares itself at the agreed price.
The deal would appear to be an attempt by Microsoft to prevent one of its competitors getting their hands on Nvidia to its own detriment - but the deal dates back significantly further than Nvidia's filing would suggest.
While the SEC filing makes reference to the deal still being active, it appears to date back to 2001 - around the time that Microsoft was launching its first entry into the video game console market with the original Xbox. Powered by an Intel processor and Nvidia graphics chip, the Xbox proved extremely popular - and a deal with Nvidia to ensure that it would maintain support for the NV2A graphics architecture makes a great deal of sense.
The deal will also have paid off in 2002, when Apple made the move to Nvidia graphics cards for its Mac range - preventing the cash-rich company from buying Nvidia to the possible detriment of Nvidia's support for its products on the Windows operating system.
Since then, however, a lot has changed. Microsoft followed the popular Xbox console up in 2005 with the Xbox 360, based on an internal project started in 2003 under the codename Xenon. The system represented a complete overhaul of the architecture, despite keeping backwards compatibility with a small selection of original Xbox games: the Intel processor was ditched in favour of a PowerPC architecture Xenon chip from IBM, while - crucially - the Nvidia graphics chip was replaced with one from rival ATI.
In 2006, chipmaker AMD decided to branch out into the graphics market - a move which has directly resulted in a new class of processor the company calls an APU, or accelerated processing unit - with a deal to acquire ATI. While neither company will admit it, it's perfectly possible that it was Microsoft's deal with Nvidia that led to ATI being chosen for acquisition.
But why is Microsoft's deal still active - to the point where Nvidia is compelled to warn shareholders about it in an SEC filing from as recent as March? Microsoft no longer uses Nvidia's technologies in its console products, and the threat of an acquisition from AMD or Apple has long since vanished.
Neither Microsoft nor Nvidia are talking, but there's been one very important development in the history of the deal: Nvidia has branched out from its core competency of graphics accelerators into the central processing market with its low-power ARM-based Tegra line of chips - and it has Microsoft's full backing.
When Microsoft announced that it would be making Windows 8 operate on both x86 and ARM architecture systems, many saw it as a chance for ARM - a company which started life on the desktop in the days of the microcomputer - to get back into laptops, desktops, and servers. A demonstration of the Windows 8 interface, which borrows the 'Metro' tile-based layout from Windows Phone 7, suggests a different direction, however: tablets.
ARM chips are popular in the tablet world already, with Nvidia's Tegra 2 dual-core processor to be found in a wealth of high-end devices - but it's Google's Android platform that can be found running on top. Microsoft is clearly aiming at the tablet market with Windows 8, and Nvidia's Tegra chips will be at the heart of that push - proven by Microsoft demonstrating a device running Windows 8 on Nvidia's as-yet unreleased quad-core 'Kal-El' Tegra 3 chip at Computex last week.
While a few years ago Microsoft could have cancelled its deal with Nvidia, the company will be keen to see the deal stand to aid in its push towards the tablet market. Nvidia, however, could have a different opinion on how it benefits from the deal - but so far has not indicated to press nor shareholders that it intends to find a way out of the agreement.