Patently-O Bits and Bytes No. 91

  • PatentLawPic666Statistics on the Use of Means Plus Function Language: Thus far in 2009 (1/1/2009 – 2/8/2009) the PTO has issued 17,206 patents. Of those, only 12% (2060) have a “means for” clause in the claim language.  Looking back one decade, 24% of patents issued in January 1999 included a “means for” clause in the claim language. Looking back two decades, 34% of patents issued in January 1989 included a “means for” clause in the claim language. Looking back three decades, 40% of patents issued in January 1979 included a “means for” clause in the claim language.
  • New Funny Blog: by appellate attorney David Mills
  • Watch The Symposium: The hardworking folks at Santa Clara’s Computer & High Technology Law Journal (CHTLJ) have posted materials and video from their conference two weeks ago. Those of you who have practiced before Judges Whyte or Ware will certainly enjoy the tribute video. [LINK] [The best portion begins at 11:20 in the Whyte video].
  • PTO Transparancy: Readers submitted two additional suggestions for PTO Transparancy
    • The PTO should calculate and publish the expiration date of each patent.
    • The PTO should publish reexamination certificates so that they are searchable. [Via NIPPER]

22 thoughts on “Patently-O Bits and Bytes No. 91

  1. 22

    GP, you clearly do not have foreign clients…

  2. 21

    The % of patents issuing with “means for” claims is proportional to the % of practitioners who still write out applications by hand, who use the flintstone-o-phone, or who have their secretary print out emails for them to read.

  3. 20

    Broje, I suspect that the foreign client who wanted M+F claims in the US priority document was thinking ahead, to FtF ROW, and having broad claims that will be manifestly entitled to the earliest achievable date, namely the US filing date.

    As to you, A: I’m intrigued by your understanding that one doesn’t resort to M+F because it’s too broad. (Too broad!!!! In Europe, we fail the examination for would be patent attorneys if our claim is in any way narrower than the broadest achievable). As I say, ROW can be thankful that the USA paddles its own canoe up its own patent creek. When it joins the ROW patent club, that will be when European and Asian industry will really find out how strong US innovation is.

    But, hey, if ROW wants the USA in the club, it must be to do America down, right. So, it stands to reason, America is better off remaining exceptional, and outside the club, doing the opposite of what ROW urges on it. Brer Rabbit and the thorn bush, anybody?

  4. 19

    my teacher told me you should not have more than one “means” in a claim, specially independent claims: just to avoid a whole range of uncertaininities and trouble to have every one of the possibilities in the claims or description, besides “means”, if I understand correctly, may get me into troubles in Europe/UK as it is would be a too general term if used without a qualifier, any comments?

  5. 18


    That’s a pretty big word for a m0r0n

  6. 17

    @ MaxDrei

    It was a foreign client that requested the M+F claims in the US originating patent applications.

  7. 16

    broje “By and large, I think patent attorneys shy away from drafting such claims because the range of equivalents is not well understood or well settled under the law,”

    Determining equivalents is easier for M+F claims because you don’t have to consider 1/3 of the tripartite test.

  8. 15

    @ Broje

    “especially regarding “future equivalents,””

    I once took part in an application that recited MPF language for electronic storage devices. In the spec, the storage means were defined as hard drives, CD Roms, floppies, etc, and any future improved storage devices.

    That patent was never litigated, but I wish it was just to see the outcome. I don’t think you can write a patent spec to change the case law.

  9. 14

    Broje, maybe that unique client was the only one who remembered that everywhere in the world, except in the USA, means plus function is the “natural” way to define an invention commensurate with the full scope of the contribution to the art. (After all, wasn’t it because claims were “too broad” that 112/6 arrived in the first place?) The rest of the world doesn’t know (yet) how lucky it is, that Americans just don’t write means plus function claims. As I keep saying, America should stay with its exceptional patent law. At least that leaves the rest of the world a sporting chance.

  10. 13

    I’ve seen a room full of patent lawyers disagree about the scope of equivalents provided by “means plus function” claims, especially regarding “future equivalents,” and whether we are talking about the “Doctrine of Equivalence” or some other standard. By and large, I think patent attorneys shy away from drafting such claims because the range of equivalents is not well understood or well settled under the law, and it puts the onus on the attorney to mention every single present equivalent for a part in the specification or potentially face malpractice. And it seems to me that most patent attorneys like to draft the type of claim that is most favored under the law at the time, not under what might be the law one day.

    But a lot of corporations just have policies against spending their money chasing those kinds of claims, and tell their attorneys what kind of claims to draft. I’ve only had one client that asked for “means plus function” claims, and that was in addition to every other type of claim you can imagine.

  11. 12

    My understanding of the CAFC’s position on “means-plus-function” as provided for in the sixth paragraph of 35 USC 112 is that the provision allows a claim to be written in a convenient shorthand, with the tradeoff for ease-of-drafting being a scope that is limited to structures disclosed in the specification that perform the recited function plus (some apparently narrow range of) equivalents thereof.

    So long as this is well understood and remains solidly the law, there’s no reason not to include a narrow claim written using means-plus-function language in parallel with a broader claim, though the cost of an extra independent claim may discourage many applicants from doing so.

    As PTO claim fees have risen, the number of independent claims in application I have written has declined. It is mainly for that reason that I have been writing fewer and fewer means-plus-function claims over the past decade or so.

  12. 11

    I would agree that use of “means for” language is limiting but I think it is oversimplistic to say that a “means for” clause should never be used in your claims as I often hear from other patent attorneys.

    Sometimes you only need two independent claims to claim the invention using structural language. In which case, it doesn’t hurt anything to use your third independent claim to cover the same ground using a “means for” clause and then throw in a couple of dependent claims spelling out alternative structures for that clause. Of course, you will also need to specifically mention several different structures/materials/acts in support of the “means for” language in the specification.

  13. 10

    I would agree with U.S. Patent Attorney from Papua New Guinea. Specifically, see Welker Bearing, link to

    Wilton, in the MPF for computer claims, read Aristocrat. Also read Lockheed Martin v. Space Systems.

  14. 9

    Regarding Re-Exams,

    What’s really funny about these re-exams is that Espacenet (the source of patents for many patent downloaders) doesn’t include them with the patent images while the PTO does. So if you type the US patent number into your robot and expect to review the claims while en route to a client meeting, you’ll be reviewing the wrong claims and have a wee bit of egg on your face.

    The re-exam gets treated like a certificate of correction by the PTO and none of this information is ever scanned. So no one can search the correct claims (not even examiners) unless you review the images rather than corresponding text.

  15. 8

    The point is that every time you put a “fancy” provision into a Statute, you get legal uncertainty, as the boundaries of meaning get attacked in real caselaw, in the years that follow. Best “Keep it Simple” in the patent statute, as with everything else. Does any other country in the world have 112/6? Are they all labouring under the impossibility of balancing fair scope of protection for inventors with reasonable legal certainty for the competitor threatened by the claim? I think not. What good did 112/6 ever do anybody, eh?

  16. 7

    “a fastener *for* fastening” would probably invoke 112(6) in the same manner as “a fastening means for fastening”


    “a fastening unit positioned between the first member and the second member so as to fasten the first member and the second member” probably would not.

    “can someone give case-law precedent for this?”

    Um, no – what am I a charity? Please search Patently-O and you will find your answers unless the dingos ate it.

  17. 6

    bleeding pen,

    As an Australian, I’m constantly intrigued by the vagaries in US law. Does “a fastener” invoke 112(6) in the same way that “a means for fastening” does? Can someone give case-law precedent for this?

  18. 5

    For the lowly law student like myself, could someone briefly explain why MPF language has fallen out of favor?

  19. 4

    Anyone that has bothered to familiarize themselves with case law from the past decade on MPF language would shy away from it.

    I do see a lot of attorneys use MPF language but shy away from explicitly stating means for. A fastener for fastener is just as much MPF as fastening means…

  20. 3

    To your credit david.

    “see that “means plus function” language was authorized by Congress for the purpose of broadening claims,”

    I must have missed that part in 112 6th, could you recite that specific portion for me?

  21. 2

    As former Federal Circuit Chief Judge Howard Markey used to say, “Why not [follow] the statute?” Some day soon, a federal court, perhaps at the urging of counsel, will read Section 112, see that “means plus function” language was authorized by Congress for the purpose of broadening claims, and construe the claims accordingly.

  22. 1

    I’m thoroughly unsurprised by the lack of “means for” language in recently issuing patents. In 2+ years of a practice that involves 95% drafting, I’ve never written a single 112p6 claim.

    – David Stein

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