9Study on Patent Claim Interpretation

Claim interpretation or construction in courts is a key factor in appropriately determining the scopes ofprotection of patented inventions and many critical decisions thereon have been made in various countries. In
1998, the Supreme Court of Japan also admitted in its decisionclaim interpretation under the doctrine ofequivalents. In the meantime, current technical innovations have brought about changes to allow new styles ofpatent claims, and how to interpret such new styles of claims is coming up for discussion.
Under the theme of finding desirable ways to interpret patent claims in Japan, research has been carriedout on existing provisions concerning claim interpretation, as well as their changes and tendencies of recent
court decisions in three countries: the U.S., the U.K. and Germany. In particular, the research was focused on
the trends of judicial precedents on the issue of the doctrine of equivalents, interpretation of claims containing
functional expressions, and interpretation of product-by-process claims.

Ⅰ Trends of U.S. Court Decisions
1

Provisions Concerning Claim Interpretation(1) Provisions Concerning Patent Infringementin the U.S. Patent Law - General Principle
Basic rules for claim interpretation and patent
infringement in the U.S. are provided in the Patent
Law, specifically in 35 U.S.C.§154(a)(1), which
provides for contents of patent right, and 35
U.S.C.§271(a), which prescribes basic rules
regarding patent infringement.
Patent infringement essentially requires, as
the premise, that an accused product be identical toa patented invention. The patented invention must
be determined with reference to the disclosure in
the specification, as clearly set forth in 35
U.S.C.§154(a)(1).
At the same time, 35 U.S.C.§112(1) provides
that a patent claim bears the most essential role inparticularly pointing out the subject matter which
the applicant regards as his invention.
(2) Literal
Infringement
and
Claim
Interpretation
Theories also support that a patent claim has
two functions: j to clarify the scope of an invention
on which patentability requirements are to bequestioned; and k to clarify the scope of an
invention on judgment on infringement.
Traditionally, many court decisions on patent
infringement disputes have relied upon a two-stepmethod which includes a step of literallyinterpreting the words of a patent claim(construction of claim (claim language)) and a stepof “reading” the result of the interpretation on an
accused item (identification of item).
The appeal court decision in Markman v.
Westview Instruments, Inc(*1). clearly held that thefirst step, i.e., interpretation and construction ofpatent claims, is a matter of law which is to beresolved by trial judges, and this decision wasaffirmed by the U.S. Supreme Court. There is still aview, however, that claim interpretation is regarded
as being a factual question to be settled by jury
trial.
The next step, i.e., identification of the item,
determines whether all the elements of the claim
read on the item, as a result of claim interpretation.
If all the elements read on the accused item, there
is literal infringement. Absence of one or moreclaim elements in the accused item does notnecessarily mean non-infringement. The nextquestion is whether the accused item infringes
under the doctrine of equivalents.
In judicial precedents, the legal nature of the“reading” work is treated as being a factual matter.
Thus, claim interpretation and the question of
infringement are different matters that should not
be discussed homogeneously but separately andindependently as distinct steps.
(3) Rules
andFactorsin
ClaimInterpretation and How These areConsidered in Judicial Precedents
In general, it is rather seldom that claim
language is definite and clear by itself and devoid of
any obscurity. Usually, therefore, several factors are
considered when patent claims are interpreted. The
aforementioned Markman appeal court decisionsuggested that claim interpretation is moreanalogous to the literal construction of the language
used in statutes than to the construction ofcontracts. The decision further held that, although
ideally no obscurity should exist in light ofknowledge of one of ordinary skill in the art, thespecification, and prosecution history, the claims
should be interpreted by focusing on how skilled
persons would have understood the claimed
invention at the time when the invention was made,and that the inventor’s intent is not significant inconstruing the claim.

(*1) Markman v. Westview Instruments, Inc., 34 USPQ2d 1321, 1326 (Fed. Cir. 1995) (in banc), aff'd, 38 USPQ2d 1461 (1996).
(*1)

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A brief summary will be given below as to how
these factors are considered in judicial
precedents.(*2)
The words used in a patent claim should begiven their ordinary meaning, unless used in a
special meaning in the specification. The words
must be clearly defined by intrinsic evidences(*3)
when they are used in a special meaning. As to theordinary meaning of each word, one can resort todictionaries.
The specification may serve as a lexicon or akind of dictionary in constructing the claims. Wheninterpreting claims, however, attention must be
paid j not to restrict the claims by “reading into”
the claims limitations from the description andembodiments in the specification, and k not toneglect, ignore or otherwise “read out” limitationsin the claims to widen the scope to include subject
matter disclosed in the specification but not claimed.
Obviously, however, the former j does not forbidinterpreting the patent claims by considering
matters that are clearly limited in the specification.
A recent court decision(*4) held that not only
“explicit” limitations but also “implicit” limitations
may be considered in claim interpretation.
The prosecution history has been given a statusof a major test in interpreting the meaning of words
in a claim. This function of the prosecution history,
however, should be clearly demarcated from therule of prosecution history estoppel that has aneffect of restricting application of the doctrine ofequivalents. The former functions as a tool or areference which helps claim interpretation,
whereas the latter is a principle originating fromthe legal theory of estoppel and prohibiting anapplicant from resurrecting a right regarding
matters that the applicant has surrendered in thecourse of prosecution.
Extrinsic evidences(*5) are usable to show theprior art at the time when the invention was made,thus help in construing the claim words. However,the Markman appeal court decision held thatextrinsic evidence should be used for the purposeof assisting courts in understanding the technicalcontext of the claim statements, but not for clearing
any obscurity of the claim words. A slight confusion
seems to exist among judgments of CAFC
regarding the extent of extrinsic evidence, as wellas to what degree such extrinsic evidence can berelied upon. The above-mentioned decision also
assumes that claim interpretation is to be treated asa matter of law. A critical opinion therefore existsthat factual matters that should be settled by jury
trial are handled by judges as being matters of law.
(4) Brief Summary
Claim interpretation is the first step of theprocess for judging infringement, whether it is a
literal infringement or an infringement under thedoctrine of equivalents. The setting-up of clear
standards for claim interpretation is therefore
significant. Practically, however, wide variation anddiversification of actual patent claims make it
extremely difficult to work out any comprehensive
standard for claim interpretation.
Basic elements of the test and scheme forclaim interpretation have been clarified appreciably
owing to accumulation of judicial precedents, andthe Markman appeal court decision has set out a“summing up” on this issue, which is relied upon in
many current court decisions.
The basic question as to whether claim
interpretation is a matter of law or a matter of fact
is still disputable. In this relation, slight confusion
still exists regarding individual issues such as thequestion of how to weigh extrinsic evidence andthe question of to what extent the claim words
should be restricted by the contents of thespecification.
2

Current Tendency of Court Decisions
Regarding the Doctrine of Equivalents(1) Tests on Application of the Doctrine ofEquivalents Set Out by the Supreme
Court in Warner-Jenkinson Co.,Inc. v.
Hilton Davis Chemical Co.(*6)(i) Tests for determination of scope of equivalents
In the in banc Hilton Davis decision, the CAFC
held that the determination of whether a difference
between an element of a patent claim and acorresponding element of an accused product issubstantial or insubstantial should follow the Triple
identity test(*7) set out in the Graver Tank Supreme
Court decision.(*8) The CAFC also made it clearthat the time criterion of possible knowledge of
person skilled in the art with respect to theinterchangeability(hereinafter, abbreviated as“possible knowledge of interchangeability”)(*9) is at(*2) Chisum on Patents (Matthew Bender, 2001) Volume 5:Chapter 18, 18.03[2][a] (Matthew Bender, 2001).
(*3) “intrinsic” evidence includes a patent's claim language, the specification and the prosecution history.
(*4) Bell Atl. Network Servs., Inc. v. Covad Communs. Group, Inc., 262 F.3d 1258 (Fed.Cir.2000); SciMed Life Sys. v. Advanced
Cardiovascular Sys., 242 F.3d 1337 (Fed.Cir.2000).
(*5) “extrinsic” evidence is all evidence external to “intrinsic” evidence, including prior art, expert testimony, etc. To which
extent “extrinsic evidence” includes is differently considered by decisions.
(*6) Warner-Jenkinson Co. v. Hilton Davis Chemical Co., 520 U.S. 17, 41 USPQ2d 1865 (1997).
(*7) Triple identity test is a test of identity in the following three elements:c substantially the same function, d substantially the
(*2)
(*6)
(*3)
(*7)
same way, and e substantially the same result.
(*4)
(*8)
(*8) Graver Tank & Mfg. Co. v. Linde Air Products Co., 399 U.S. 605,
85 USPQ 328 (1950).
(*5)
(*9)
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the time of infringement rather than the time atwhich the patent application was filed.
The Warner-Jenkinson Supreme Court decision
did not give a denial to the test in the CAFC in bancdecision, but held that the CAFC should refine theformulation of the test for equivalence in theorderly course of case-by-case determinations andthe Supreme Court should leave such refinement to
the CAFC’s sound judgment.
(ii) Regarding “intention to infringe”
The Supreme Court decision held thatwhether or not the doctrine of equivalents is to be
applied should not be determined by whether there
was an intention to infringe.
(iii) Regarding “all elements Rule”
It was held by the Supreme Court that theequivalency should be determined throughcomparison of each element of the claimed
invention rather than the invention “as a whole”.
(iv) Regarding prosecution history estoppel
The Supreme Court held that any invention
surrendered by a patentee must be excluded fromthe scope of equivalence, due to the legal doctrineof prosecution history estoppel. It was also
confirmed that estoppel applies in particular to
restrictive amendments effected to render a claim
patentable over prior art, and that when the reason
for the amendment is unclear and not establishedby the patentee, estoppel should be applied basedon a presumption.
(2) CAFC Decisions After the Warner-Jenkinson
Supreme Court Decision(i) Criterion of scope of equivalence
The Warner-Jenkinson Supreme Court Decisionleft the task of refinement of formulation of the test
to CAFC’s sound judgment. At present, there are
two procedures available for the determination of
the scope of equivalence: one is the triple identity
test and the other is the test regarding the possible
knowledge of interchangeability. Although several
decisions have been made by the CAFC withrespect to the triple identity test(*10), none of thesedecisions clearly showed the extent of “substantiality”.
Thus, the CAFC decisions were made on acase-by-case basis. In re Kemco Sales, the CAFC
held that when a difference under the triple identity
test is “substantial”, the issue of possible

knowledge of interchangeability is moot. The CAFC
decisions also show that the difference is likely tobe regarded as being “substantial” when an accused
product has been designed around the patent(*11) or
when an accused product was cited as a prior art inan Office Action in the course of prosecution (*12).
(ii) CAFC decisions regarding the all elements rule
There are many cases which dealt with the“limitation by limitation rule” that questions
whether an accused product has elements
corresponding to elements of a patent claim andthat permits arbitrary combinations of suchcorresponding elements(*13). There are also cases
which strictly followed the all elements rule anddenied equivalents. In one case, the doctrine ofequivalents was not applied for the reason thatelements of a patent claims were definite(*14). In
another case, application of the doctrine ofequivalents was denied for the reason thatapplication of this rule would render the limitationsin the claim meaningless(*15). A case also exists inwhich claims were interpreted in a restrictive
manner in the light of the disclosure in thespecification, without relying on the doctrine ofequivalents(*16).
(iii) Regarding the time criterion for the issue ofthe possible knowledge of interchangeability
According the decision holding that thequestion of equivalence is determined at the time of
infringement, equivalency may be extended suchthat an element of a device that is not an
equivalent at the time of start of the businessbecomes an equivalent at a later time. After theWarner-Jenkinson Supreme Court decision none of
the CAFC decisions discussed about this issue.
Opinions exist, however, that a defense based onprior art should be considered by taking into
account not only the state of the art at the time ofpatent application but also that at the time of
infringement.
(iv) Cases regarding prosecution history estoppel
There has been no consistency in the CAFC
regarding how strictly prosecution history estoppel
shall be applied.
Therefore, the Festo CAFC in banc held(*17) as
follows:
c The “substantial reason related to patentability”(*9) The Graver Tank Supreme Court decision suggests “whether persons reasonably skilled in the art would have known of
the interchangeability” as test criteria of doctrine of equivalents, so that it is appropriate understanding “would have
known”.
(*10) Instituform Tec. Inc. v. CAT Contracting Co., 48 USPQ 2d 1610 (Fed. Cir. 1998); Kemco Sales Inc. v. Control Papers Co.,
54 USPQ 2d 1308 (Fed. Cir. 2000).
(*11) Roton Barrier, Inc. v. The Stanley Works, 37 USPQ 2d 1816 (Fed. Cir. 1996).
(*12) National Presto Indus., Inc. v. West Bend Co., 37 USPQ 2d 1685 (Fed. Cir. 1996).
(*13) Festo Co. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 50 USPQ(*11)
2d 1385 (Fed. Cir. 1999), etc.
(*12)(*14) Sage Products, Inc., v. Devon Industries, Inc., 44 USPQ 2d 1103(*13)(Fed. Cir. 1997).
(*14)Cir. 1998).
(*15) Dr. Raymond G. Tronzo, v. Biomet, Inc., 47 USPQ 2d 1829 (Fed.
(*15)(*16) Scimed Life Systems, Inc. v. Advanced Cardiovascular Systems,
Inc., 58 USPQ 2d 1059 (Fed. Cir. 2001).
(*16)
(*17)
Festo
Corp.
v.
Shoketsu
Kinzoku
Kogyo
KabushikiCo.,
56
USPQ2d1865 (Fed. Cir. 2000) (en banc).
(*10)
(*17)

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is not limited to amendments made to overcome
prior art but includes any reason that affects
issuance of a patent.
d Even a “voluntary” amendment can create
prosecution history estoppel.
e If a claim amendment creates prosecution
history estoppel, there is no room at all for
application of the doctrine of equivalents.
f When a presumption is made of prosecution
history estoppel due to the reason that explanation
for a claim amendment is not established, there is
no room at all for application of the doctrine ofequivalents.
While some of CAFC decisions made after theFesto in banc decision seem to strictly follow theholdings of the in banc decision, there is also founda decision holding that the rule of prosecution
history estoppel should not apply to redefinition ofelements in a patent claim(*18).
The Festo in banc decision was brought up to
the Supreme Court by an appeal with respect to theabove points of dispute c and e and received by
the same. The U.S. Government issued a brief inregard to the trial at the Supreme Court. The
Government’s brief is summarized as follows.
The complete bar approach excludes
application of the doctrine of equivalents to“after-arising technologies” developed after a
restrictive amendment. In the meantime, theWarner-Jenkinson Supreme Court’s decisionholds that presumption of prosecution history
estoppel based on restrictive amendment isrefutable. Prohibition of refutation to
presumption based on “after arisingtechnologies” is incompatible with the same
Supreme Court’s decision that affirmed
protection against infringement based oninterchangeable after- arising technology.
Various other opinions have also been
submitted, and how the Supreme Court will rule on
this case is attracting attention.
(v) Test of the doctrine of equivalents with“hypothetical claim”
A theory called “hypothetical claim theoryrule” is acknowledged that any product which iscovered by a hypothetical claim does not constitutean infringement under the doctrine of equivalents if
such a hypothetical claim is not patentable overprior art, although this theory was not discussed in
the Warner-Jenkinson Supreme Court’s decision.
(3) Regarding Purport of Application of theDoctrine of Equivalents
The doctrine of equivalents is not a remedy for
mis-drafting of a patent claim. In the meantime,

Sage Products Inc., v. Devon Industries, Inc., heldthat the doctrine of equivalents should not beapplied to the reasonably anticipated coverage to beclaimed at the time of filing of a patent application.
This holding is considered to suggest that thedoctrine of equivalents has major purpose toprotectthe scope of substitution by anafter-arising technology that did not exist at thetime of filing, rather than substitution by atechnology anticipated by a person skilled in the art
at the time of filing upon reading a claim.
The question of whether the doctrine ofequivalents covers “subject matter disclosed in thespecification but not claimed” is being at issue inJohnson & Johnson Associates, Inc. v. R.E. Service
Co., Inc. Considering the above-mentioned purport,
the Court will presumably decide that the scope ofequivalence does not extend to encompass matters
not set forth in the claims (*19).
(4) Conclusion
It is a current trend in the U.S. to give muchweight to the notice function of patent claims. Thus,
the practice of claim interpretation is changing
towards easier understanding of the scope by thegeneral public than ever. The strict application ofprosecution history estoppel held by the Festo inbanc decision, as well as the all element rule,
symbolically demonstrates this current trend in the
U.S.
From the viewpoint of emphasizing the noticefunction, clear and decisive application of thedoctrine of equivalents will be needed on acase-by-case basis. In particular, it will become
more important to set up clear standards regarding
the “substantiality” factor of the triple identity test,
as well as criteria for “interchangeability” and“possible knowledge of a person skilled in the art”.
Relationship between the theory of prosecution
history estoppel and the doctrine of equivalents will
also be an important issue.
3

Trends of Decisions Involving Interpretationof Functional Claims(1) Introduction
In the U.S., a special provision regarding
functional claims is stipulated, namely, 35
U.S.C§112(6) serves as a compromise measure
between practical requirements and the principle ofdistinctness. Examination in practice and claim
interpretation is exercised on the premise of thisspecial provision. This special provision may seemto impose a different discipline in the U.S. Patent
Law from the Japanese Patent Law which lacks(*18) Turbocare Division of Demag Delaval Turbomachinery Co. v. GE, 60 USPQ 2d 1017 (Fed. Cir. 2001).
(*19) Johnson & Johnston Associates Inc. v. R.E. Service Co., Inc., 238 F.3d 1347, 2001 U.S. App. LEXIS 4038 (Fed. Cir.
2001)(en banc)（this case was decided on March 28, 2002, after the report of this study was published, to hold that thescope of equivalence does not extend to encompass any invention disclosed in the specification but not set forth in the
(*18)
(*19)
claims.
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such a provision. This provision, however, isconsidered as expressing a guide to interpretationof functional claims when the basic principle of the
U.S. Patent Law is applied to functional claims, or
how to accept functional claims. An important hint
exists in this special provision of the U.S. Patentlaw as to how to handle similar functional claims
under Japanese Patent Law.
(2) Functional Claims Under Distinctness
Rule
An opinion has existed that functional claims
do not comply with the principle of distinctness set
forth in 35 USC §112(2). In fact, in the Halliburton
Supreme Court decision, a patent claim wasdecided as being invalid as being indefinite and too
wide. In order to address this problem, the U.S.
Congress revised 35 U.S.C. in 1952 to add §112(6)which admits functional expressions of patentclaims under certain conditions, thus legislatively
resolving the issue of conflict between functional
expressions of patent claims and the principle ofdistinctness.
(3) How Functional Claims Are Treated in
Prosecution
Conventionally, the USPTO has made it a rule
not to apply §112(6) in the course of prosecution,and examined applications based on literalinterpretation.
This practice has been criticized that claim
interpretation during prosecution is improperly
wide as compared to restricted interpretation ofclaims of patented invention under §112(6).
Under these circumstances, the Donaldson inbanc decision(*20) disaffirmed the conventional
examination practice and held that §112(6) should
be considered also in the course of prosecution. As
a result, in the current examination procedure, oncethe examiner finds thatthe claim fall under anequivalent of the prior art and that the prior art isan equivalent of the structures or the like disclosed
in the specification, the burden of proof is on theapplicant to show that the prior art is not an
equivalent.
(4) Whether to Apply 35 USC §112(6)Special claim interpretation is required when§112(6) is applied. This gives rise to a question as
to on what occasion should this Section be applied.
In Unidynamics Corp. v. Automatic ProductsInternational(*21), the CAFC held that §112(6)applies even when a functional expression lacks theword “for”. In Media Communications LLC v.
ITC(*22), a lower court’s decision which admitted theapplication of §112(6) was overturned by the CAFC

for the reason that lack of words “means for”
creates a presumption that resorting to §112(6) was
not sought for so that a word in a claim should beconstrued to define a specific structure. Even when
the above-mentioned presumption is made, §112(6)may apply if means for performing a specificfunction is not properly written in a functional
claim(*23).
This serves as a relief measure against
invalidation of a patent based on failure to meet thedistinctness requirement.
For patentees, §112(6) is both advantageousand disadvantageous. This Section, when applied,
may removea reason for invalidation based on
unduly wide, obscure, and indefinite claim wording,i.e., failure to meet the distinctness requirement.
On the other hand, the same Section serves torestrict the scope of an element in a claim of apatent only to structure, material, or acts describedin the specification, and equivalents thereof.
(5) Literal Construction of Functional Claims
Under the legal theory of “reverse doctrine ofequivalents”, an accused product may not infringe aclaim even if all the elements in the claim literally
read on the accused product. With regard tofunctional claims provided in §112(6), a accused
product does not infringe such a claim even if theclaim literally reads on the product, provided thatthe product is not identical or equivalent to thestructure, material, or acts disclosed in thespecification. Thus, §112(6) is regarded as being alegal measure which authorizes the reverse
doctrine of equivalents(*24).
Therefore, in order that a functional claim isliterally met by an accused product, a court mustfind that the product has is identical or equivalent interms of structure, material, or acts disclosed in thespecification, and that the function is identical(*25).
Whether the requirement of “identity offunction” is met can be determined by evaluating
the “equivalents” prescribed in §112(6) in the lightof tests that are similar to those applied for thedoctrine of equivalents. Anyway, identity of thefunction is an essential factor.
Obviously, the provision of “equivalents
thereof” prescribed in §112(6) and the doctrine ofequivalents have different purposes and are applied
on different occasions. It is necessary, however, toclarify the difference between them.
In the aforementioned Valmont case, the court
held that, while the doctrine of equivalents relies
upon the triple identity test, §112(6) requires only acomparison between a structure disclosed in the(*20) In re Donaldson Co., 29 USPQ 2d 1845 (Fed. Cir. 1994).
(*21) Unidynamics Corp. v. Automatic Products International, 48 USPQ 2d 1099 (Fed. Cir. 1999).
(*22) Media Communications LLC v. ITC, 48 USPQ 2d 1880 (Fed. Cir. 1998).
(*23) Micro Chem. Inc. v. Great Plains Chem. Co., 52 USPQ 2d 1258 (Fed. Cir. 1999).
(*20)
(*23)
(*24) Valmont Indus. Inc. v. Peinke Mfg. Co. Inc., 25 USPQ2d 1451 (Fed.
Cir. 1993).
(*21)
(*24)
(*25) Pennwalt Corp. v. Durand-Wayland, Inc., 3 USPQ 2d 1737, 1739
(Fed. Cir. 1987).
(*22)
(*25)

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specification and that of an accused product,differently from the doctrine of equivalents.
In Chuninata Concrete Concept, Inc. v. Cardinal
Indus, Inc.(*26), the court confirmed that §112(6) andthe doctrine of equivalents have different origins
but should rely upon similar tests. Based on thisprinciple, the court made it clear there are twopoints of difference between them: namely, c thetime criterion for the question as to insubstantial
difference under the doctrine of equivalence is thetime of infringement, whereas, for §112(6), thetime criterion is the time of issue of a patent, sothat §112(6) requires that only the art that existed
at the time of issue of the patent be considered, in
contrast to the doctrine of equivalents, which
requires that technologies developed after theissue of the patent also be considered; and d for
non-essential difference under §112(6) it isrequired that the functions be identical to eachother, while the doctrine of equivalence inquires
only whether the functions, ways and the results
are substantially the same, respectively. The court
also held that, when an equivalent matter that was
known at the time of issue of a patent is considered,such a matter does not come under the doctrine ofequivalents if it is decided as being not equivalent
under §112(6).
In Odetics case(*27), the court affirmed thatwhether the requirement of §112(6) is met isdetermined in the light of tests that are similar to
those used under the doctrine of equivalents, on
condition that the functions are identical. At thistime, however, the court disaffirmed the use of the
all elements rule, for the reason that element-byelement comparison through an analysis of aclaimed structure is inappropriate because thestructure corresponding to the claimed functions as
a whole alone can limit the claim.
As will be understood from the foregoing,
there is no comprehensive rule concerning the“equivalents” prescribed in §112(6) and a question
still remains in this connection.
(6) Functional Claim and the Doctrine ofEquivalents
Conventionally, use of the doctrine ofequivalents in interpretation of functional claims
has been considered only as “a saying by the way”
(obiter dicta). This common understanding was
relied upon for the first time by the CAFC in WMS
Gaming, Inc. v. International Game Tech.(*28)
In this case, the CAFC denied literal
infringement on a functional claim because function
is not identical and affirmed infringement under thedoctrine of equivalents for the reasons that thefunction of the accused product was substantiallythe same as that of the claimed invention and thatthe accused product produced the same result inthe same way as the claimed invention.
Under the current U.S. case law, there are two
types of patterns of infringement in connection withfunctional claims: one in which the function of an
accused product is not identical but substantially
identical to that disclosed in the specification; andthe other in which interchangeability withtechnologies developed after the filing of patentapplication is questioned.
4

Trends of Decisions on Interpretation of
Product-By-Process Claims(1) Definition of “Product-By-Process Claim”
A “product” claim inherently defines a productby structural features and may be infringed by a
product on which the claim literally reads, even if
the infringing product is manufactured by adifferent process disclosed in the patent.
A “product-by-process claim” is a claim inwhich at least a part of a product is defined by aprocess. Applicants generally prefer product claims
because product-by-process claims are liable to beinterpreted restrictively to cover only products
produced by the processes set forth in such claims.
Applicants, however, are not reluctant to submit
product-by-process claims particularly when theyfind it difficult to define the natures of invented
products in addition to product claims. The USPTO
admits such a way of claim drafting as long as thedistinctness requirement is satisfied(*29).
(2) Interpretation of Product-By-Process
Claims in Prosecution
The patentability of a product-by-process claim
is examined by construing the claim broadly.
When a prior art shows a product which isreasonably understood as having only a slightdifference from the claimed product, the claim isrejected as being anticipated by or obvious from theprior art. Since the USPTO themselves is unable tophysically compare the prior art product and theclaimed product by actually manufacturing the priorart product, the examining procedure allows
examiners to reject claims based on prima facie lackof novelty or prima facie obviousness, thus
reducing the burden of proof on the examiners(*30).
(3) Interpretation of Rights Covered by
Product-By-Process Claims
There are two inconsistent CAFC decisions on
the interpretation of product-by-process claims: one
holding that a product which is the same as the(*26) Chiuminatta Concrete Concept Inc. v. Cardinal Indus. Inc., 46 USPQ 2d 1752 (Fed. Cir. 1998).
(*27) Odetics Inc. v. Storage Tech Corp., 51 USPQ 2d 1225 (Fed. Cir. 1999).
(*28) WMS Gaming Inc. v. International Game Tech., 51 USPQ 2d 1385 (Fed. Cir. 1999).
(*26)(*29) MPEP § 706.03(e) (1974).
(*27)
(*29)
(*30) MPEP § 2113 (2001).
(*28)
(*30)
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product defined by a product-by-process claim falls
within the scope of the claim regardless of the
production process; and the other holding that a
product is not covered by a product-by-process
claim if produced by a different process.
In Scripps case(*31), the CAFC took a position
that the claimed product is not limited to that
prepared by the process set forth in the claims. The
court held that, since a claim must be interpreted in
the same way both in determination of validity of
the claim and determination of infringement, thecorrect reading of product-by-process claims is thatthey are not limited to products produced by theprocess stated in the claims. In the Scripps decision,
however, the CAFC held that there was no
infringement by applyning the reverse doctrine ofequivalents because the accused product wasdifferent from the patentee’s product and excelled
the latter in purity. In contrast, in Atlantic
Thermoplastics case(*32), Atlantic, relying upon the
Scripps decision, asserted that the process set forthin its product-by-process claims did not limit thescope of the claimed product. The CAFC rejected
this assertion for the reason that Scripps decision
did not fully study the Supreme Court decisions.
The CAFC then cited some Supreme Court
decisions which limited the scope only to productsthat were prepared by processes set forth in theclaims, and held that the “process limitations”
should be read into the scope of the claims, unlike
the administrative decision on patentability in theexamination procedure.
In view of the fact that two contradictorydecisions were made by two different assemblies,
Atlantic requested an in banc rehearing where its
assertion was denied although four judges wereagainst the denial(*33).
Subsequent district court decisions also varied.
One district court decision held that a productprepared by a different process does not fall within
the scope of the claim even if the product per se is
the same, whereas another district court decision
held that a product is encompassed by a claim if the
product per se is the same as the claimed product,
regardless of the preparation process(*34). The latter
decision was appealed to the CAFC and how the
CAFC will deal with this case is drawing attention.
(4) Opinion of Professor Takenaka of
University of Washington
In the research committee for discussion of the
US situation organized under this study, Professor
Takenaka of the University of Washington raised
the following point.
It is difficult to examination this product-byprocess type claims with respect to the enabling

requirement, the description requirement and thedistinctness requirement. As it is impossible to add
a structural feature to this type of claim after
patenting, there is a substantial risk of being
invalidated. In addition, since the CAFC ismaterially negative to the “experimental use
doctrine”, competitors cannot experimentally
manufacture a patented product and compare theproduct with their own products. Furthermore,element-by-element comparison is impossible
because there is no recitation of structurallimitations. Product-By-Process claim, therefore, is
not considered significant in claim drafting.
(5) Consideration
If a product, which is produced by a process
different from that stated in a product-by-process
claim but the same in nature as the claimed product,is encompassed by the claim, any third party will be
unduly burdened of manufacturing the patented
product in order to compare such a product with
its own product. In addition, it is considered difficult
to specify the nature of the product defined by a
product-by-process claim. As inventions of technicalfields with rapid progress, e.g., biotechnology, may
not be defined with structural characteristics at thetime of filing of a patent application, it may be areasonable strategy to specify a part of a claim by aprocess to secure a right and, when the structure of
the invention has been made clear, to extend thescope of the right to cover the same productprepared by a different process. It is to be noted,
however, that a patent claim has a primary functionof making notice to third parties. In order to avoid
any unforeseeable disadvantage to caused to third
parties, any attempt to extend the right toencompass products made by a process other thanthe disclosed process requires sufficient care.
It might be possible for courts to interpret a
product-by-process claim broadly as done by the
USPTO, when evaluating the validity of the claim.
However, if a product produced by the processstated in the claim alone can infringe, it might beunnecessary to determine the validity of the claim
with respect to the other scope of the claim. Thus,
it will be sufficient for the courts to interpret theclaim in the same way as that for the determinationof infringement.
As discussed above, it seems that the majority
of decisions hold that a product-by-process claim
covers only the product produced by the processstated in the claim. Nevertheless, it will not beappropriate to unconditionally apply this rule of claim
interpretation in the course of the examination
procedure, regardless of the disclosure in thespecification. From this point of view, it might(*31) Scripps Clinic & Research Fdn. v. Genentech, Inc., 18 USPQ 2d 1001, 1016 (Fed. Cir. 1991).
(*32) Atlantic Thermoplastics Co. Inc. v. Faytex Corp., 23 USPQ 2d 1481 (Fed. Cir. 1992).
(*32)(*33) Atlantic Thermoplastics Co. Inc. v. Faytex Corp., 23 USPQ 2d 1801 (Fed. Cir. 1992).
(*33)(*34) Trustees of Columbia University v. Roche Diagnostics GmbH, (D. Mass. No. 93-11512-NG, 2000).
(*34)
(*31)

IIP Bulletin 2002

● 102 ●

be not useless to determine novelty andnon-obviousness of the claimed product per se of a
product-by-process claim, while construing theclaim without limiting it to the process set forth in
the claim, as done by the USPTO in theprosecution.
The nature of product-by-process claims
cannot be described simply. In particular, there aremany issues to be considered on the claim
interpretation in infringement litigation, such as thewording of individual product-by-process claims,
consistency with the disclosure in the specification,
features which render the patentability, and so forth.
Reducing these issues to the sole issue of whether
or not the scope of claim is limited to the productproduced by the process in the claim and settling
this issue alone will not give a proper guide to claim
interpretation in the United States. From theconcrete situations and the opinions of Judges of
the Scripps case and Atlantic Thermoplastics case,
it is seen how the interpretation of product-byprocess claims is difficult. At the same time,versatility in claim interpretation according to thespecifics demonstrated in these cases is informative.
Attention should therefore be focused on future
court decisions in this regard.

Ⅱ Trends of Court Decisions in the
United Kigdom
1

Characteristics of Claim Interpretation
Specific to the U.K. Among European
Countries

It is known that claims are interpreted rather
strictly in the U.K. In contrast to Germany where
the central definition principle is dominant, the U.K.
patent system is oriented towards a peripheral
definition principle seeking legal stability. Thisdifference symbolically appears in the Epilady cases
in which an identical technology was decided as
infringing in Germany and not infringing in the U.K.
While as a part of the activities towards
harmonization in the European community, aneffort to clarify standards of claim interpretation has
been made with Article 69 of the European Patent
Convention and the protocol concerning constructionof Article 69, the differences by country, however,are said to be still innegligible.
The practice of claim interpretation in the U.K.
originates from the 1852 Act which set out the dutyof submitting a written specification. Then, the1949 Act determined that a claim is the “definitionof the scope sought for a patent”, progressively
emphasizing the peripheral definition function ofclaims in the patent system. In the meantime, the“Pith and Marrow” theory emerged in 1877 which
determines that infringement is established when
the pith and marrow of invention and an accused

product are the same, thus affording a rather
relaxed view of claim interpretation. This theory,
however, did not provide any clear standards orcriterion. A protocol concerning EPC concluded
in 1973 suggests that a compromise between thestrict claim interpretation dominant in the U.K. andthe rather loose standard relied upon in Germany
would be appropriate. In compliance with thisprotocol, U.K. Patent Law was fully revised in 1977
including Section 125 providing claim interpretation.
Regarding claim interpretation, a decision wasmade in 1982 in Catnic, working out a new standard
called the “purposive construction” theory which
established a basis for current claim interpretation.
Then, in the Improver case, a decision was madeattempting to formulate the Catnic standard.
These two decisions were made on patents
under the old Patent Law. Thus, the “purposive
construction theory” presented in the Catnic caseis considered as a standards for claim interpretation
effective as a common law under the old Patent Law.
Whether the “purposive construction theory”(Catnic=Improver standards) should apply topatents under the current Patent law is an issue.
Although some lower court decisions held thatclaim interpretation should strictly follow thestatutory construction of Article 125 envisaging
current trends in European community rather thatrelying upon the Catnic standard underthe common
law, judicial precedents and majority opinion affirm
the effectiveness of the Catnic decision as aprecedent in claim interpretation of patents under
the current Patent Law.
2Standards for Claim Interpretation(1) Catnic=Improver Test
The claim interpretation standard referred toas the Catnic=Improver test used by U.K. courts
has the following three factors or requirements.
First requirement:
Does the variant have a material effect upon
the way the invention works? If yes, the variant is
outside the claim. If no:)Second requirement:
Would this (i.e. the fact that variant has nomaterial effect) have been obvious at the date of
publication of the patent to a reader skilled in theart? If no, the variant is outside the claim. If yes:
Third requirement:
Would the skilled in the art neverthelessunderstood from the language of the claim thatpatentee intended that strict compliance with theprimary meaning was an essential requirement of
the invention? If yes, the variant is outside theclaim.
A comparison between these three requirements
and the five requirements adopted in Japan provides
the following.
The first requirement of the Catnic=Improver● 103 ●IIP Bulletin 2002

test corresponds to “identity of operation/working
effect” required in Japan. The second requirement
corresponds to the “obviousness” concept inJapanese practice, although the Catnic=Improver
test significantly differs in that it recites the
publication date of the patent as the critical date.
The third requirement presumes that the firstand second requirements are satisfied. Thus, thethird requirement questions how a person skilled in
the art would have evaluated the fact that thepatentee dared to draft a narrow claim despite thefact that a person skilled in the art would havereasonably been enabled to draft a broader claim.
Infringement is denied if the answer to thisquestion is that a person skilled in the art upon
reading the claim language had understood that thepatentee selected a specific wording with theintention that the wording should be construed
literally and strictly. This approach is similar to theconcept of “intentional exception” discussed inJapan. Strict application of the third requirement of
the Catnic=Improver test will leave substantiallyno room for the so-called doctrine of equivalents.
Thus, how to deal with the third requirement is an
issue.
The first and second requirements are
considered as matter of fact, while the third
requirement is considered as matter of law. Thus, it
is generally understood that the first and second
requirements play a role of assessing premises thathave to be cleared before entering into the questionof the third requirement.
In the U.K., there is no distinct legal theory
which would correspond to prosecution history
estoppel. A legal theory referred to as the “Gillette
defence” has been known as a legal measure forso-called defense on prior art. This theory, however,is not used so frequently because validity of patents
can also be determined in infringement law suits in
the U.K.
(2) Article Relied on for Claim Interpretation
The basis for claim interpretation is found in
Article 125 of the current U.K. Patent Law (1977).
Article 69 EPC, which is recited in Article 125,
Paragraph 3 of the U.K. Patent Law, contains similar
provisions. The protocol concerning construction of
Article 69 has a paragraph concerning equivalence.
The last sentence of the protocol devoted toequivalence was added by a revision made in 2000.
This sentence, however, is nothing but the result ofcompromise, and various opinions presented in
preparatory discussion are not adopted in the
protocol. Future trends must be followed to see
how the last sentence will influence claim
interpretation practice.
3

Recent Decisions

The following is an overview on recent
decisions that affirmed infringement based on the

IIP Bulletin 2002

Catnic=Improver test.
In the Kastner v. Rizla case, the Patent County
Court denied infringement but the Court of Appeal
decided that there was infringement. The Appeal
Court decision ([1995]PRC 585) held that there are“obvious mechanical equivalents” which arenothing but substitutions with a known technology,
and “mechanical equivalents” which are to be
judged on infringement after a more normative,
purposive construction. In this case, the Appeal
Court affirmed the infringement based on the
purposive construction of a claim. More specifically,
focusing on the third requirement of theCatnic=Improver test, the Appeal Court held thata person skilled in the art would never haveconsidered that the patentee intended to strictly
comply with the claim wording, since the variant
was immaterial.
In the Biolet v. Valmet case, ([1997] RPC 479),
the court decomposed a claim into elements andexecuted purposive construction on an element
which was not found in an accused product, leading
to the conclusion that there was infringement.
There are several similar decisions.
The following cases denied infringement.
The decision in the Daily v. Etablissements
Fernand Berchet case ([1993] RPC 357) denied
infringement based on the first requirement of theCatnic=Improver test. In this case, the court heldthat there was no infringement because theoperation/result of the patented invention were notachievable by the accused product. In a very recent
decision in the Amersham Pharmacia Biotech v.
Amicon case ([2001] EWCA Civ 1042), the court
denied infringement for the reason that the scope ofprotection cannot be extended to encompass a
defendant’s technology which relied upon an
entirely different mechanism, though thedefendant’s technology achieved the same result as
the patented invention.
The decision in the PLG Research v. Ardon
International ([1955] FSR 116) is a case in which
infringement was denied based on the second
requirement of the Catnic=Improver test. In thiscase, the court held that there was no infringement
because it was not obvious for the person skilled in
the art whether substitution with an accused
product had no material effect on theoperation/result.
The
secondrequirementoftheCatnic=Improver test was also addressed in thecurrently noted American Products v. Novartis
Pharmaceuticals case (the decision of the High
Court:[2000] RPC 547, the decision of the Courtof Appeal:[2001] RPC 159). The patent in
dispute pertained to Rapamycin, a known
immunosuppressant, and included Swiss-type
claims directed to a second medical use of the agent
and failing to mention any derivative. The
defendant was sued for infringing the patent by the● 104 ●

use of a derivative. The High Court affirmed
infringement for the reason that it was expectable
by a skilled person that the derivative had a highprobability of producing a similar effect, although
the mechanism of the medical effect produced by
Rapamycin and, accordingly, what derivative would
produce the same medical effect were not known toa person skilled in the art at the priority date of thepatent application. This High Court decision was
reversed by the Court of Appeal. The Court ofAppeal held that the expectation by a person skilledin the art of the fact that the derivative would
achieve the same operation/result alone wasinsufficient to satisfy the second requirement, anddenied fulfillment of the second requirement for thereason that it should have been clear to a person
skilled in the art that the derivative in question
would achieve the same operation/result. The
Court of Appeal further held that a person skilled in
the art would have understood that the patentee did
not mention any derivative because the patentee
intended to strictly comply with the meaning of theclaim wording, thus establishing failure to meet thethird requirement. For these reasons, the Court ofAppeal held that there was no infringement. Thiscase was then appealed to the House of Lords. How
the House of Lords will decide on this case is amatter of great interest.
The decision in the Optical Coating Lab. v.
Pilkington case([1995] RPC 145) is noted as
denying infringement based on the failure to meet
the third requirement. More specifically, the court
denied infringement for the reasons that thepatentee willfully restrained from claiming thetechnology of the defendant’s product in order toavert any suspicion on the validity of the patent,
and that a person skilled in the art would consider
that the patentee did not have intention to have thetechnology of the defendant’s product encompassedby the scope of the patent. It is to be noted that the
court held that it is the case that the third
requirement is not satisfied where a “plausible
reason” exists for the patentee to intend to restrict
the scope strictly in compliance with the claim
wording.
While
judicial
precedents
are
being
accumulated, the points to be clarified in regard to
the Catnic=Improver test seems to clarify thetime criterion to be applied to the second
requirement, threshold of the second requirement,
and the threshold of the third requirement.
4Interpretation of Functional Claims andProduct-By-Process Claims

As is the case in Japan, no specific provisions
are legislated in the U.K. in regard to theinterpretation of functional claims and product-by-process claims. These types of claims are interpreted
and enforced in the same ways as those for ordinary
claims. In the entrusted research of this time, it
has been reported that no particularly serious
discussion has been made in the U.K. regarding theexamination and interpretation of these two typesof claims.

Ⅲ Trends of Court Decisions inGermany
1

Provisions
Interpretation

Concerning

Claim(1) Provisions in the Current Law
Article 69 (1) EPC and Article 14 of theGerman Patent Law pertain to claim interpretation.
Construction of Article 69 EPC follows the protocol
to the EPC.
A German judicial precedent holds that the
stipulation in the protocol also applies to theconstruction of Article 14 of the German Patent
Law which contains the same prescription(*35). This
rule clearly excludes the former practice which
permitted a broad interpretation departing fromclaims based on a concept so-called “General
Inventive Idea”. Thus, the stipulation in the
protocol has naturally invited a change in the way ofinterpreting the scope of protection of inventions inGermany. This protocol is regarded as being
enforceable by law.
(2) Movement Toward Revision
A diplomatic conference of Contracting Statesof the European Patent Organization was held inJanuary 2000, in which a proposal was made toincorporate additional paragraphs relating to thedoctrine of equivalents and file wrapper estoppel
into the protocol concerning construction of Article
69 EPC. In another diplomatic conference held in
November 2000 at Munich, the U.K. strongly
protested against the proposal. Germany also madea stiff opposition against a proposal to set thecritical time for evaluation of equivalence to thetime of infringement. In consequence, a paragraphrelating to the doctrine of equivalents was added
after a modification of the original proposal,
whereas an additional paragraph relating to filewrapper estoppel was canceled.
2

Identical Infringement

Under German patent practice, the concept
of “literal infringement” is referred to as
wortsinngemässe/identische Verletzung (wordmeaning/identical infringement).
However, the concept of identical infringement
is not to simply determine the scope of protection(*35) Benkard, Patentgesetz 9. S. 532 (C. H. Beck, 1993); BGH GRUR(*35) 1986, 803, 805 - Formstein.
● 105 ●IIP Bulletin 2002

by the meaning of the claim wording alone. Morespecifically, there is a holding stating “It is notallowed to be apprehended by the wording of aclaim. Technical significance of the subject of an
invention may not be also neglected.” Anotherholding states “Solving means, which is known to aperson skilled in the art as being able to achieve
the same effect by its ordinary function, also fallunder the meaning of the word ‘technicallycomprehensible solving means’, even if not
explicitly disclosed in the patent specification.”(*36)
The determination on patent infringement
begins with defining the scope of identical
infringement, i.e., the meaning of the claim. Thereis a judicial precedent which held that “Whentesting whether a patent has been infringed, thefirst step is to establish what are the terms of theclaims as they would be understood by a person
skilled in the art, which involves ascertaining what
their wording means to such a person i.e. theircontextual meaning. If, where a specific embodimenthas been contested, the substance of the claim as
thus contested is being used, then the protected
invention is being used.” (*37)
A theory known as the Formstein defense,referred to also as defense of free state of art,
denies the existence of infringement for the reason
that a mode of art allegedly infringed cannot
constitute any invention in view of the state of art
as of the time of filing (or priority date) and,hence, there should be no patent infringement.
Judicial precedents in Germany, however, do notallow this type of defense to be relied upon for thedetermination of identical infringement, due tosharing of power and authority between theinstitution, which grants patents and decides
invalidity and the courts, which deal withinfringement disputes. Therefore, if an accused
product is determined as falling within the scope ofidentical infringement of a patent and validity of thepatent is questionable, the only way left for the
defendant is to institute an invalidation lawsuit
before the German Federal Patent Court.
3

Infringement By Equivalents(1) ConfirmationofInfringement
byEquivalents in Formstein decision
The Formstein decision confirmed as follows inregard to the scope of equivalents to be applied
after Section 6 (a) of the 1976 Act came into effect.
“In our recognition, extending the scope ofprotection to cover equivalent embodiments
beyond the claim language coincides with the legal
approaches of other Contracting States of theEuropean Patent Convention, although theprocedure for seeking the objective scope ofprotection and the range of protection vary fromcountry to country. For patents derived fromapplications filed on or after January 1, 1978, thescope of protection in regard to the working of an
invention by equivalents is defined by the content
of scope of a claim which is to be confirmed throughinterpretation.”(2) Requirements for Equivalentsc Whether an accused product solves the sameproblem as that solved by the invention.
d Whether the solution by the accused productrelies upon the same operation/result as that relied
upon by the invention.
e Whether a person skilled in the art could
understand based on the claimed invention that theoperation/result achieved by the accused product isthe same as that of the invention.
(3) Time Criterion for Evaluation ofEquivalents
In Germany, the priority date, i.e., the date offiling of application, is the critical date for theevaluation of equivalents. German patent practicerequires that the subject of a patent should beinquired based on the disclosure in the specification
with reference to knowledge of a person skilled in
the art at the priority date (filing date) of patentapplication. In compliance with this requirement, it
has been made a rule that a question as to whether
an art is equivalent to a patented invention be
addressed based on the state of art available at thetime of the priority date (filing date) of patentapplication.
The purpose of this rule is not to exclude
from the scope of equivalents any mode of
execution of invention which uses any substituent
element which produces the same effect as anelement in a claim but did not exist at the time ofpriority date (filing date). Thus, the purport ofthis rule is to question, based on the state of art
at the time of priority date (filing date), whether
it was possible to use such a substituent elementin place of the element set forth in the claim,
rather than the availability of the substituent
element per se.
(4) Formstein Defense
In regard to the scope of equivalence, analleged infringer can defend that the invention of
the allegedly infringed patent has no patentabilty inview of a prior art or the state of art at the time ofConvention Priority or filing of the patentapplication.
As stated before, this type of defense is notallowed when identical infringement is established.
Therefore, this type of defense must undergo first
determination of the fact that the accused producthas all the “Merkmale” of the claimed invention
and performs the function of the claimed invention(*36) Benkard a.a.O.,S.532.
(*37) BGH 1988.6.14－Ionenanalyse, IIC 2/1991, 249.

(*36)
(*37)

IIP Bulletin 2002

● 106 ●

so that the accused product falls within the scope ofprotection, and further determination or, at least,
presumption of the fact that at least one “Merkmal”
is equivalently used in the accused product.
4File Wrapper Estoppel

Prosecution history estoppel is not considered
in determining the protection scopes of patented
inventions. A ground for this practice is found in a
judicial preceding(*38) which states to read c“Neither Section 14 nor the protocol prescribes
prosecution history estoppel as interpretationmeans for determining the scope of protection.
They do not mention any other means ofinterpretation.” and d “If the patent specification
does not describe the scope of protection in amanner comprehensible to a person skilled in theart, it is not allowed in an infringement proceedings
to rely upon any statement in prosecution file so as
to interpret the claim to give a scope narrower thanliteral interpretation.”
This means that disclaimer and restriction of
the scope of protection must be clearly shown inthe specification.
Nevertheless, contents of a file wrapper may
exceptionally be considered in determining thescope of protection, when such contents are known
to a person skilled in the art(*39).
5

Functional Claims

In Germany, there is no provision which would
correspond to 35 U.S.C.§112(6). However, a
judicial precedent allows to define an invention by astatement of a result to be achieved or the nature of
the invention without stating structural features(*40).
In the entrusted research in this study, it has beenreported that the number of patent applications
including this type of claims is increasing withincrease of patent applications directed to
information technologies.
This type of claim is allowed only when it is
impossible or completely insubstantial to define aninvention by structural features.
At the same time, functional claims must be
accompanied by a disclosure of technical teachings
full enough to enable a person skilled in the art tocarry out the invention over the entire coverage ofthe functional expression based on the functionalfeatures set forth in the claim, without
unnecessarily efforts. A functional claim, therefore,should c set forth means for solving a problem
rather than the problem alone and d enable aperson skilled in the art to generalize the functionalfeatures over the entire coverage of the functional
expression.
Determination of the scope of a functional
claim also follows Section 14 of the German Patent
Law. Therefore, all the means that achieve thesame effect or characteristic as those stated in theclaim fall within the scope of protection. Thus, afunctional claim is a claim which, by a functional
expression, inclusively defines all possible meansthat achieve the same function, regardless ofwhether such means are set forth explicitly(*41).
A counterbalance to this practice is that thequestions on novelty and inventive step apply tothe entire coverage of the generalized functional
claim.
6

Product-By-Process Claims

As is the case of functional claims, German
practice allows an invention of an article or productto be claimed in terms of a production process or anapparatus used in the production. This type of claim
writing tends to raise a question particularly when
the invention pertains to a novel chemical matter.
In regard to a patent of such a technical field, a
representative “Kommentar” in Germany states toread “The chemical matter itself is protected
regardless of the production process. Whether thenovel chemical matter is defined in the claim interms of a chemical formula, production process, ora production apparatus does not matter.” (*42)
Claiming a product invention in terms of a
production process is exceptionally permitted only
when no other suitable method of definition isavailable, and is required to definitely specify the
product.
Patentability is evaluated on the claimed
product per se, and the scope of protection covers
any and all products having the same characteristics
without being restricted to the product produced by
the process set forth in the claim.
The decision in Trioxan (GRUR 1972, 541;3
IIC 1972, 226) and the decision in Farbbildroehre(GRUR 79, 461, 464) are major decisions renderedby the Federal Supreme Court.

Ⅳ ClosingWithin the framework of this study, in addition
to the regular committee, a conference wasorganized inviting Mr. Randall R. Rader, a judge ofCAFC, and Professor Toshiko Takenaka of the(*38) BGHZ 3,365,370- Schuhsohle;BGH GRUR 59,317,319- Schaumgummi.
(*39) Benkard, a. a. O., S. 520. BGH 25 IIC 420 [1994].
(*40) See, BGH GRUR 85,31-Acrylfasern; Schulte “Patentgesetz mit Europaeishem Patentuebereinkommen” Aufl.,S.575.
(*38)(*41) Schulte a.a.O.,S.504, Benkard a.a.O.,S.493.
(*39)
(*41)
(*42) Benkard a.a.O.,S.507., BGHZ 53,274,282-Schädlingsbekämpfungsmittel,
BGHZ 54,1,22(GRUR 72,80)-Trioxan.
(*40)
(*42)
● 107 ●IIP Bulletin 2002

Washington University, for exchange of opinionswith the members of the committee. Researches in
Europe were entrusted to Simons & Simons in
London and Vossius & Partners in Munich.
The study was first focused on clarification of
the structure of rules concerning patent
infringement, as well as on general principles ofinterpretation of claim language.
A research was also made in regard to thedoctrine of equivalents. In regard to the U.S.,
analysis was made mainly on the decisions after
the Warner-Jenkinson Supreme Court decision. The
analysis made it clear that the Warner-㩷 Jenkinson
decision, which held that the critical time for theevaluationof“possible
knowledgeofinterchangeability” under the doctrine of equivalents
is the time of infringement, has raised a new issue
or problem that the range of equivalents may
inconveniently extend by time. A tendency tostrictly apply the rule of prosecution history
estoppel is also observed, as typically seen in
CAFC Festo in banc decision, 2000.
In the U.K., the theory of “purposive
construction”, i.e., the Catnic=Improver Test,
provides the basic rule for claim interpretation.
Current decisions relying upon “obvious mechanicalequivalents” or “mechanical equivalents” are also
noted. As to the second requirement of theCatnic=Improver test, the critical time for theevaluation of obviousness is ruled to be the date of
publication of the patent, which raised an important
issue to be settled. In regard to the third
requirement, it is to be noted that a current
decision held that this requirement is not met when“plausible reason” exists for the patentee to intend
to restrict the scope of the right strictly in
conformity with the claim wording.
In Germany, the claim interpretation follows
the rule held by the Formstein Federal Supreme
Court decision of 1986, and the doctrine ofequivalents is developed under this rule. In the
diplomatic conference for revision of EPC held in
2000, a proposal was made to modify the protocol
concerning construction of Article 69 EPC so as tomake it clear that the critical time for thedetermination of equivalence is the time of
infringement. It has been reported, however,Germany did not agree to this proposal andasserted that the critical time should be the priority
date.
In regard to interpretation of functional
claims, the U.S. reconfirmed legislative history andlegislative intent of 35 U.S.C.§112(6). It was found,however, that opinions are still fluctuating in regard
to the relationship between the doctrine ofequivalents and equivalents per se, as well as themethod for determining whether the doctrine
should apply and the method of determining thescope of equivalence. It is to be noted that thedoctrine of equivalents is applicable also to

IIP Bulletin 2002

functional claims, and that there are two types ofissues: one which arises when the function of an
accused product is not identical to that disclosed
in the specification but is regarded as being
substantially the same therewith; and the other inwhichinterchangeability
withtechnologies
developed after the filing of patent application isquestioned.
Functional claims is also accepted in the U.K.
It seems that method or standard for interpretationof this type of claim is not at issue in the U.K. The
German Patent Office also accepts functional claims
but under a strict condition. In the entrusted
research in Germany, it has been reported that afunctional claim covers all that fall within the scope
generalized from the functional expression of theclaim.
Finally, referring to product-by-process claims,
USPTO in prosecution evaluates the patentabilityon the product per se, while affording a broad scopeto this type of claim. However, court decisions ininfringement litigations are divided into two types:
one which holds that an accused product isencompassed by a patent regardless of the
production process if the product itself is identicalto the claimed product, and the other which
excludes any product produced by a different
process. Such diversification of decisions seems to
be attributed to differences in factors such as thestyle of expression of the process in the claim,features that render the inventions patentable, andtechnical fields to which inventions pertain. The
conclusion available at the present stage is thatnone can hastily determine which one of these two
types of decisions is reasonable and correct.
Product-by-process claims are accepted also in
the U.K., where no issue seems to exist regarding
the way or standards for interpretation of this typeof claims. In Germany, this type of claims has been
accepted for a long time, and a rule has been
established that any and all products which are
identical to the product produced by executing
the claimed invention fall within the scope ofprotection. These features regarding handling ofproduct-by-process claims in the U.K. and Germany
are contrastive to those in the U.S.
Each and every respects that have been madeclear through this study are considered to be
critical and significant when compared to decisions
made in our country.

● 108 ●㩷(Researcher:Takashi
Ohno)(Researcher:
Keiji Ohno)