Free-software-MP3 enthusiasts who believe in the protective power of ignorance, and who are not already sticking their fingers in their ears and shouting "la la la", may wish to do so before reading further. (They may also wish to start work on their affidavit demonstrating that their local ISP prevents them from Googling "sisvel MP3" for themselves.)
At least some MP3 player chipset vendors seem to think their customers need patent licenses from both Sisvel (or its US subsidiary Audio MPEG) and Thomson (sole licensor for Fraunhofer MP3 patents; see below). (Reportage at http://www.electronics.globalsources.com/gsol/I/Flash-MP3/a/9000000062166.htm ; note that it misreports some Microsoft patents relating to WMA DRM as "MP3 patents".) Audio MPEG's website claims traction on software implementations and (!) computers generally. But they seem to be the licensing agency for non-DVD-decoding-as-such use of audio patents that Philips filed in the course of developing their DVD silicon (see http://www.licensing.philips.com/licensees/conditions/dvd/documents1008.html ); and certain vitally interested parties don't seem to worry about those patents when no MPEG-specific silicon is involved. For instance, judging from the literature that came with my iPod mini (a spiff from an employer, unsuitable for resale because of its non-Apple-approved-warranty-voiding engraving; don't blame me for SUPPORTING the EVIL PROPRIETARY audio DRM, mmkay?), Apple doesn't think it needs licenses for Philips patents for its MP3 decode functionality (implemented in software on a weird dual ARM core chip, according to http://www.arm.com/markets/mobile_solutions/armpp/7518.html ). They have licensed the Fraunhofer / Thomson suite, although it is worth noting that iTunes (bundled with the iPod, and also available to all Mac users as a free-as-in-beer download) has MP3 encoding capabilities and Apple may have done an all-you-can-eat deal with them covering both encoding and decoding. Starting from the URL that Apple supplies and clicking a couple of times, we get to http://www.iis.fraunhofer.de/amm/legal/index.html (stating that Thomson is Fraunhofer's sole licensor) and thence to www.mp3licensing.com. Better not click http://www.mp3licensing.com/patents/index.html if you don't want to know the patent numbers involved, and you certainly had better not (for example) Google "patent 5,924,060", click through to patft.uspto.gov, read patentee Brandenburg's disclosure and claims, and conclude (as I do, but IANAL and all that) that to get something both non-obvious and actually reduced to practice by the inventor you need to intersect at least claims 1, 3, 6, and 7. All the patent's claims are dependent on claim 1, which is (as usual with this sort of patent) so broad as to be obviously invalid by itself as a description of the scope of the patent. The claim that reflects the principal substance of the invention is number 7. IMHO efficient psycho-acoustic quantization was potentially the sort of invention suitable for patenting in 1987, depending on your perspective on the purpose of patent law. Granting that for the moment, the fun is in determining which of the other claims are essential to the invention. If I were to consult my personal sense of what rises to a proper level of originality, in ignorance of the details of the prior art, I would say that 2, 4, 5, and 8 are sufficiently routine that the patent can't be dodged by using some alternative to them. But the meat of the patent is in the actual reduction to practice (i. e., a concrete quantization scheme specific to the human perception of music, of which these claims are merely implementation details) of the psycho-acoustic premise in claim 7, without which there is no invention to speak of. And until you specify both the entropy encoder (3) and the DCT or its cousin (6), there's nothing to reduce to practice. IANAL, least of all a qualified US patent attorney, but that's kind of how this first, rough-cut, "things that are obvious to one skilled in the art" stage of the infringement analysis works as I understand it. YMMV; and even if the above is correct as far as it goes, a court under the jurisdiction of the Federal Circuit might well reach different opinions about which claims are essential to the invention and which are not. For one thing, there may be prior art that did psycho-acoustic quantization using a DCT and entropy encoding (those bits are laws of nature, and in any case already well understood in 1987) but did it less well because they chose alternatives to 2, 4, 5, and 8. Anyway, the alleged infringer is entitled to argue that, to the extent that the plaintiff holds a valid patent, the court should limit its reach (based on its claims, its disclosure, the prior art, and other factors) in some way that causes it to fall short of covering the allegedly infringing product. This may or may not involve demonstrating that this product is itself inventive to within a patent standard, in some way that differs from an essential claim in the claimed patent. If I were defending, say, an Ogg/Vorbis implementation against a claim that it infringes US Patent 5,924,060 (did I mention that IANAL?), I would argue that a wavelet transform is sufficiently different from a DCT (or a DFT or "a transform using Time Domain Aliasing Cancellation", whatever that is) that Brandenburg's disclosure doesn't teach much about how to design a psycho-acoustic quantization scheme for wavelet coefficients. If I were defending an MP3 decoder, I would say instead that the decoder doesn't realize the invention because it doesn't know or care whether the encoder used the quantization scheme that the disclosure teaches. Only if I were attempting to defend a literal implementation of the disclosed method (i. e., an MP3 encoder) would I be reduced to claiming that the entire patent is invalid because psycho-acoustic audio encoding schemes are somehow not the sort of invention that Congress had the power and desire to encourage when they last revised the USPTO's charter. I would be loth to go out on that limb, because as far as I can see, the semi-empirical quantization thresholds in an MP3 encoder are every bit as worthy of patent protection as the "bottle-engaging means" in my favorite corkscrew (US Patent #4,703,673; but see the sad story on "friction-reducing material" claims at http://www.corkscrewnet.com/EllisCsinCourt.htm ). In sum: I've got bad news, folks. Arriving at an informed opinion about where, for patent law purposes, the borderline between invention and discovery should lie is _hard_work_. So is the due diligence expected of those who stake their fortune on the premise that a presumptively valid patent should never have been granted. You say you want a revolution? I suspect that, European Parliament or no European Parliament, "No Software Patent" placards are about as convincing to a competent court as Chairmain Mao posters were in the Beatles' day. Cheers, - Michael Disclaimer: IANALIAJ, this is emphatically not legal advice, I reserve the right to argue otherwise in another context, and I have reached these opinions without applying any inside knowledge that I may have of the legal affairs of Sisvel, Thomson, Fraunhofer, Apple, or any other participant in the MPEG IP wars. I did, however, make use of the aforementioned corkscrew, strictly for demonstration purposes. :-)
