Subject: Day 8 Self Study Course:  

Aug 28, 2009 (Fri)


summarized by Tatsuo Yabe



(C) Prior Art preclusion;


Wilson Sporting Goods v. David Geoffrey & Assocs (DGA) (Fed. Cir. 1990)


Patentee: Wilson Sporting Goods -- USP4560168

Accused Infringer -- DGA (and Dunlop)


USP'168 is about a certain configuration of dimples on a golf ball cover.  The critical feature of the claim is locations of the dimples on the ball.  The object is to create a more symmetrical distribution of dimples.


The issue is how the prior art limits the coverage under DOE.  More specific issue is whether the accused product that may be within the range of DOE be excluded from the DOE scope when there is the prior art which is close to the structure of the accused product.  In other words, the specific issue is whether Wilson has proved that a hypothetical claim, similar to claim 1 but broad enough to literally cover Dunlop's balls, could have been patentable.




In order to determine if the prior art limit the range of DOE to exclude the accused product, the following steps to be exercised:


(i) Write a hypothetical claim that literally cover the accused product;

(ii) Determine whether the hypothetical claim could have been allowed by PTO over the prior art?

(iii-A) If the hypothetical claim could NOT have been allowed, then it would be improper to permit the patentee to obtain that coverage under DOE.

(iii-B) If the hypothetical claim could have been allowed, then it would be proper to permit the patentee to obtain the coverage under DOE.


In short, the above is the test to see whether the accused product is closer to prior art than to the claim.  The burden is on Wilson (patentee) to prove the range of equivalents which it seeks.  The patent owner always owes the burden of proving infringement.


In order for a hypothetical claim to literally cover Dunlop's balls, its limitations must permit 60 dimples to intersect the great circles by at least 9 thousandths of an inch.  Then, it is to be determined if this hypothetical claim could have been patentable in view of the prior art Uniroyal ball.



The hypothetical claim limitation reads on any ball which has less than 14% of its dimples intersecting great circles.  Uniroyal ball meets this limitation.  There is no principled difference between the hypothetical claim and the prior art Uniroyal ball.  Thus, Wilson 's claim 1 cannot be given a DOE range which is broad enough to encompass the Dunlop balls.




1. The Hypothetical claim;

- the use of which is not practical at all!  WHY?


  -- No matter how precisely worded the jury instruction may be, at least in the eyes of a jury, a hypothetical claim analysis blended together separate issues of (i) infringement; and (ii) patentability;

  -- Most judges are busy enough to deal with real problems in litigation.  Asking the judges to evaluate patentability of a hypothetical claim, in addition to having them to rule on the validity of claims, may be too hard!


2. The Fed Cir itself has stepped back from application of the Hypothetical claim analysis under Wilson Sporting Goods


- With a 40% of reversal of district court claim construction by the Fed Cir, the district courts will not be happy to construct a hypothetical claim, construe it, and determine its patentability over the prior art.  In Key Mfg v. Mocrodot (Fed Cir 1991).


- In Key Mfg (Fed Cir 1991), it is mentioned that Wilson simply acknowledges that prior art limits the coverage available under DOE such that a range of equivalents may not embrace inventions already disclosed by prior art.


- In General Am. Transp. Co. v. Cryo-Trans (Fed Cir 1996), the court applied the Wilson 's teachings without constructing any hypothetical claims.


3. Burden of Proof:


- Under Wilson , the patentee has the burden of proving the patentability of hypothetical claims.


- However, in National Presto Indust., Inc. v. West Bend Co. (Fed Cir 1996), the court suggested that the infringer has the burden of proving that the accused device is in the prior art:  ...When the patentee has made a prima facie case of infringement under the DOE, the burden shifts to the accused infringer, not to the trial judge, to come forward with evidence to show that the accused product is in the prior art.


4. No Defense to Literal Infringement:


- In Wilson Sporting Goods, the court dealt with a defense of practicing the prior art to an accusation of infringement under DOE, whereas in Tate Access Floors v. Interface Architectural (Fed Cir 2002), the Fed Cir dealt with a defense of practicing the prior art against literal infringement.


- Literal infringement is determined by construing the claims and comparing them to the accused device, not by comparing the accused device to the prior art.  In other words, there is no requirement that the accused device be non-obvious in light of the prior art.  --> The Def should rely on a defense of invalidity, instead of relying on the Wilson Sporting Goods when Def is accused of a literal infringement.


5. Can the hypothetical claim add additional limitations to avoid the prior art and thus permit an assertion of DOE?  Nooops!!!


- A hypothetical claim analysis is not an opportunity to freely redraft granted claims!

- Slight broadening is permitted but not narrowing!

- Hypothetical claim analysis cannot be used to redraft granted claims in litigation by narrowing and broadening a claim at the same time!



(D) Disclosed but unclaimed subject matter;


Johnson & Johnston v. R.E. (Fed Cir. en banc 2002)


Patentee: Johnson -- USP5153050

Accused infringer: R.E. Service Co.


The USP'050 relates to the manufacture of printed circuit boards.  Printed circuit boards are composed of extremely thin sheets of conductive copper foil which is joined to sheets of a dielectric (non-conductive) resin-impregnated material.  In creating these circuit boards,@workers manually handle the thin sheets of copper foil during the layering process.  In order to prevent the damages during manual handling, the claimed invention adheres the fragile copper foil to a stiffer substrate sheet of aluminum.


The issue is whether the range of DOE will be limited by the unclaimed disclosures of the embodiment.




    -- YBM Magnex v. ITC (Fed Cir. 1998);


    The patent claimed a permanent magnet alloy comprising certain elements, including 6000 to 35000 ppm oxygen.  The accused device is a similar magnet alloy with an oxygen content between 5450 and 6000 ppm, which was allegedly disclosed but not claimed in the '439 patent of YBM.   


    The court did not create a new rule that DOE cannot encompass subject matter which was disclosed in the spec but not claimed.



    -- Maxwell v. Baker (Fed.Cir. 1996)


    The Patent claimed a system for attaching together a mated pair of shoes.  Maxwell disclosed the inner and outer soles of the attached shoes.  Maxwell disclosed in the spec but did not claim, fastening tabs that could be switched into a lining seam of the shoes.


    DOE cannot recapture unclaimed but disclosed subject matter.  Unclaimed subject matter is dedication to public.




USP'050 describes the composition of the substrate sheet:

While aluminum is currently the preferred material for the substrate, other metals, such as stainless steel or nickel alloys, may be used.


USP'050 specifically limited the claims to "a sheet of aluminum" and "the aluminum sheet".



Having disclosed without claiming the steel substrates, Johnston cannot now invoke the DOE to extend its aluminum limitation to encompass steel.  In other words, Johnston cannot assert the DOE to cover the disclosed but unclaimed steel substrate. 


YBM Magnex decision conflicts with this holding, thus this en banc court overrules that case.






Notes: Important so read carefully pages 484 to 486


1. How is this rule of law likely to impact disclosures in spec?


2. Is this legal limitation on the DOE necessary?


3.  Does this limitation exclude only those equivalents explicitly listed in the spec?


    For instance, if claims said "aluminum" and spec said aluminum or steel, and the accused product uses iron. Under Johnson & Johnston, the patentee cannot claim that steel and aluminum are equivalents, but how about iron and aluminum?


    Another example is if the claim says "pH of 6.0 to 9.0, spec says 5.8 to 10.0 pH.  Under Johnson & Johnston, the patentee cannot claim that 5.8 and 6.0 are equivalents.  How about the infringing device that uses 5.7 pH?  Can the patentee claim that 5.7 and 6.0 are equivalents?


4. Sufficiency of the disclosure:


    Suppose the spec discloses a potential embodiment but does not have a sufficient disclosure to satisfy an enablement requirement under 112(1), and the claim does not claim such embodiment.  For instance, an inventor mentions in the spec that his system could be potentially used on the internet but does not provide enough disclosure to enable it when the use of the internet was still in the developing stage.  Under the situation, is it proper to trigger the public dedication rule with respect to the disclosed but unclaimed subject matter (the embodiment of the system used on the internet)?


    The Fed Cir twice addresses as to what disclosure is sufficient to trigger this bar to the DOE ("the disclosure-dedication rule").


    In PSC Computer v. Foxconn (fed Cir 2004), the court suggested that, to be dedicated to the public, the embodiment must satisfy the disclosure obligations of 112(1).


    In Toro Co. v. White Consol (Fed Cir 2004), subsequent to the PCS (2004), the court rejected the PSC and held that "the disclosure-dedication rule" does not impose a 112(1) requirement on the disclosed but unclaimed subject matter.  The court of Toro applied the public dedication rule even though the spec did not enable that embodiment.


    Do you agree with Toro that 112(1) should not govern the public dedication rule?


(E) Advantage rule/Spec based estoppel;


Vehicular Tech (Power Trax) v. Titan Wheel (Tractech); (Fed. Cir. 1998)


Patentee: Power Trax -- USP5413015

Accused Infringer: Tractech


USP'015 is directed to an improved locking differential with one of major improvement, that is, newly designed spring assemblies that use 2 concentric coil springs and a pin.  Claim 1 includes biasing means with a spring assembly consisting of two (2) concentric springs.


The written description makes clear a function of the spring assembly, emphasizing repeatedly the capacity of the inner spring to serve as a back-up, or replacement, or redundancy for the outer spring in the event of the failure of the outer spring, as a significant betterment over the prior art.  Similar advantages for having 2 concentric springs are mentioned in (i) Background of the Invention; (ii) Summary of the Invention; and (ii) Description of the Preferred Embodiment.


The issue is whether the advantage mentioned in the spec limits the range of DOE, when the accused product does not meet the advantage.


The spring-plug structure of the accused product is entirely incapable of performing the key back up function (advantage mentioned 'repeatedly' in the spec), thus strongly suggesting that the spring plug structure of the accused product is more than insubstantially different from the claimed spring assembly.


Judge NEWMAN: dissenting


    The panel majority imposes a new rule of law that overrides the facts of equivalency.  In other words, the panel majority bars liability of infringement by an equivalent device if the equivalent device does not possess the unclaimed advantages or functions described in the spec.  This new rule is contrary to the law of claim interpretation and it is contrary to the precedent of equivalency.


    The panel majority holds that the advantages mentioned in the spec, although not included in the claims, must be possessed by the accused device before there can be a finding of infringement by equivalency.


    The correct procedure for determining equivalency as to claim clause [5], the biasing means, would be to consider the concentric springs set forth in the claim and the spring/plug of the accused device, and to determine equivalency on the entire record of similarities and difference in function, way, and result.


    The majority panel possibly fell into error by confusing claim construction with infringement, because the majority cites Vitronics (Fed Cir 1996) for its holding that the written description is "the single best guide to the meaning of a disputed term."  However, here in this case, there is no term meaning in dispute.




1. Specification estoppel?


    - The court compared this doctrine to prosecution history estoppel (PHE) but explicitly noted that the case does not involve that issue. 


2. Disclosure incentives:


    - Patent applicants often include language suggesting the benefits of the claimed invention over the prior art because these disclosures can help inform the public about the nature of the invention.  What incentive do cases like Vehicular and SciMed create for disclosing information in the spec?  If these cases reduce the incentive to disclose, do these cases undermine the quid pro quo nature of the patent system?


3.  Reading limitations into the claim?


    - Do you think that the majority panel in Vehicular is improperly reading a limitation of spec into the claim?  In determining whether two items are equivalents under DOE, is F/W/R test under Graver Tank sufficient?


4.  Equivalence under 112(6).


    Skip it!




(F) Limited prior use rights. 


 35USC273 (1999) only for B-Model Patents


It codifies a prior user rights defense to infringement which is limited to business method patents.

It provides a defense to infringement of a business method patent if the Def:

    (1) reduce the invention to practice more than 1 year before the effective filing date of the patent; and

    (2) commercially used the subject matter before the effective filing date of the patent.