Doctrine of Equivalents in Patent Legislation: An Analysis of the Epilady Controversy, The


THE DOCTRINE OF EQUIVALENTS IN PATENT LITIGATION:
AN ANALYSIS OF THE EPILADY CONTROVERSY

I. INTRODUCTION

Today the primary element in the growth of modem economies is the
development and use of new ideas and new technologies.' "[T]he ability
to create and make use of new ideas and new technologies is increasingly
becoming a factor which distinguishes the successful from the unsuccessful,
be it in nation-to-nation or firm-to-firm competition."2 Because of the economic
importance new ideas and technologies play in the marketplace, most industrial
nations afford inventors of new products or processes protection within their
borders.3

This protection is provided by what is called a patent. A patent is an
instrument granted by a government or sovereign of a country which gives
the patentee an exclusive right to use the new product or process for a period
of time. However, the exclusive use is only applicable in the territory of the
country granting the patent. In the United States, a patent confers the right
to exclude others from making, using or selling the patented invention for
seventeen years.4 Today, even though most industrial nations grant patent
protection, the methods used to determine the scope of a claim and whether
the claim encompassesthe accused product or process vary from one industrial
nation to another.

Direct infringement of a patent occurs in one of two ways: literal or
by equivalence. Literal infringement is essentially outright duplication of
the patented device and is rarely litigated.5 Therefore, the vast majority of
infringement disputes involve the doctrine of equivalents. Patent attorneys
know from experience that a patent system not recognizing infringement by
equivalence would provide little protection for patented products or processes.
Recognizing the important role the doctrine of equivalents plays in patent
protection, it is equally important that the doctrine is applied uniformly wherever
patent protection is afforded. Because patent protection is based on the patent
laws of the country granting the patent and the political agendas of each country
differ, global uniformity in regard to equivalency has yet to be achieved.
Without a worldwide uniform equivalents doctrine, the degree of patent
protection will vary from one nation to the next. The global inconsistencies
of claim interpretation force industries holding foreign patent rights to allocate
additional capital for legal counsel interpretation of these inconsistencies, which

1. R. MICAHAEL GADBAW & TIMOTHY J. RICHARDS, INTELLECTUAL PROPERTY RiGHTS

1(1988).
2. Id.

3. Id.
4. 35 U.S.C. §§ 154 & 271 (1988).
5. Graver Tank & Mfg. Co. v. Linde Air Products Co., 339 U.S. 605, 607 (1950).



IND. INT'L & COMP. L. REv.

effectively reduces the capital available for activities vital to the long run
financial success of these industries, such as research and development and
purchases of machines and equipment.

The purpose of this note is to illustrate the lack of harmony in determining
infringement by equivalency between the United States and the Member States
of the European Community (E.C.). In order to familiarize the lay reader
with the doctrine of equivalents, Part II of this note briefly describes the doctrine
as it is applied in the United States. Part III then focuses on international
patent protection and the role the doctrine of equivalents plays in the E.C.
Part IV discusses the contradictions among the national courts of the E.C.
in applying the doctrine of equivalents, and illustrates these contradictions
by analyzing the Epilady controversy. Briefly, the Epilady controversy involved
an infringement dispute between a European Patent holding Panamanian
company and an American-based company. The patented device, the Epilady,
is a depilatory device used to remove hair from the arms and legs of women.
What is particularly interesting about the Epilady dispute is that when the
Panamanian company sought to enforce its European Patent in various E.C.
national courts, some national courts found infringement and others did not.
This inconsistency occurred even though each national court considered the
same patent, the same infringing device, a similar set of facts, and applied
the same uniform standard of interpretation. The Epilady controversy serves
as a dramatic illustration of the contradictions among the national courts of
the E.C. in applying the doctrine of equivalents. Lastly, as a possible solution
to the inconsistent applications of the doctrine of equivalents, Part V discusses
how the current draft of the Patent Harmonization Treaty will facilitate
harmonization of the doctrine of equivalents worldwide.

II. PATENT INFRINGEMENT AND THE DOCTRINE OF EQUIVALENTS

IN THE UNITED STATES

With respect to a utility patent, the United States Government grants,
for the term of seventeen years, the right to exclude others from making, using,
or selling the patented invention in the United States. Violation of this right
is a tortanalogous to trespass'for which the patent holder may bring a civil
action in Federal Court. Violation of this right to exclude others from making,
using, or selling the patented invention in the United States is called direct

6. 35 U.S.C. § 154 (1988).

7. Carbice Corp. of America v. American Patents Development Corp., 283 U.S. 27,
33 (1931).

8. Thompson-Houston Elec. Co. v. Ohio Brass Co., 80 Fed. 712, 721 (6th Cir. 1897).
9. 35 U.S.C. § 281 (1988).

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DOCTRINE OF EQUIVALENTS

infringement. The statutory definition of direct infringement, on its face, appears
to be quite simple. Section 271 (a) provides: "[e]xcept as otherwise provided
in this title, whoever without authority makes, uses or sells any patented inven-
tion, within the United States during the term of the patent thereof, infringes
the patent."1 Although the statutory definition of direct infringement appears
to be straight forward, the definition requires the courts to conduct two difficult
inquiries: the determination of the scope of the claims, as a matter of law,
and the factual finding of whether the properly construed claims encompass
the accused structure."

Direct infringement can be found in one of two ways: literal or by
equivalence. To establish infringement of a patent every limitation set forth
in a claim must be found in the accused product or process exactly or by a
substantial equivalent. 2 In determining both literalism and equivalence,
the focus must be on the elements of the individual claim rather than the
invention as a whole. 13

A. Literal Infringement

Literal infringement is found when the words of the claim literally read
on the accused subject matter and such subject matter embodies the essential
characteristics of the invention defined by the claim. The United States Supreme
Court in Graver Tank & Mfg. Co. v. Linde Air Products Co., summarized
the process of determining literal infringement of a patent as: "[i]n determining
whether an accused device or composition infringes a valid patent, resort must
be had in the first instance to the words of the claim. If the accused matter
falls clearly within the claim, infringement is made out and that is the end
of it."v 4

As most patent attorneys know though, literal infringement is basically
outright duplication of the patented device and is rarely litigated. 5 Most
infringement disputes involve an accused device which has not copied every
literal essential characteristic of the patented device. More often the accused
device embodies elemental substitutions and minor changes that take the accused
device outside the scope of the literal meaning of the patent's claims.

10. 35 U.S.C. § 271(a) (1988).
11. McGill Inc. v. John Zink Co., 736 F.2d 666, 671 (Fed. Cir. 1984) (citing SSIH Equip.

S.A. v. USITC, 718 F.2d 365, 376 (Fed. Cir. 1983)), cert. denied, 469 U.S. 1037 (1984).
12. Johnston v. IVAC Corp., 885 F.2d 1574, 1581 (Fed. Cir. 1989).
13. Pennwalt Corp. v. Durand-Wayland, Inc., 833 F.2d 931,935 (Fed. Cir. 1987), cert.

denied, 485 U.S. 961, 1009 (1988).
14. Graver Tank, 339 U.S. at 607.
15. Id.

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IND. INT'L & COMP. L. REv.

B. Equivalency (Doctrine of Equivalents)

If the requirements of literal infringement are not met, infringement
may still be found by applying the doctrine of equivalents. According to
the doctrine of equivalents, if the words of the claim do not literally read on
the accused subject matter, but the accused device performs substantially the
same function in substantially the same way to obtain substantially the same
result, there is infringement unless the patent holder is estopped from broadening
the scope of the claim beyond the literal meaning of its words.'" The patentee
has the burden of proving the accused device infringes the patent's claims,
and to do so under the doctrine of equivalents requires a showing that all three
components of the equivalency test-function, way, and result-are met.'7

Therefore, to find infringement under the doctrine of equivalents, a patentee
must prove by a preponderance of the evidence 8the substantial identity as
to each of the function, way, and result prongs of the doctrine of equivalents.' 9

1. Interchangeability Factor of Equivalency

An important factor in the determination of equivalence is whether persons
reasonably skilled in the art would have known of the interchangeability of
an ingredient not contained in the patent with one that was.2" The patent
specification need not disclose the equivalent element and the fact that it is
a proper substitute in order for the doctrine to apply.2' The Federal Circuit

16. E.g., Pennwalt Corp., 833 F.2d at 934 (citing Perkin-Elmer Corp. v. Computervision
Corp., 732 F.2d 888, 901-02 (Fed. Cir. 1984), cert. denied, 469 U.S. 857 (1984) and Graver
Tank, 339 U.S. at 608); Stewart-Warner Corp. v. City of Pontiac, 767 F.2d 1563, 1570-72
(Fed. Cir. 1985) (citing Graver Tank, 339 U.S. at 609 (quoting Sanitary Refrigerator Co. v.
Winters, 280 U.S. 30, 42 (1929))).

17. Universal Gym Equip., Inc. v. ERWA Exercise Equip. Ltd., 827 F.2d 1542, 1548

(Fed. Cir. 1987).
18. Smithkline Diagnostics, Inc. v. Helena Labs. Corp., 859 F.2d 878, 889 (Fed. Cir.

1988).
19. Maltav. Schulmerich Carillons, Inc., 952 F.2d 1320, 1325 (Fed. Cir. 1991), cert.

denied, 112 S. Ct. 2942 (1992).
20. Perkin-Elmer Corp., 822 F.2d at 1535 (citing Graver Tank, 339 U.S. at 609); Palumbo

v. Don-Joy Co., 762 F.2d 969, 975 (Fed. Cir. 1985) (citing Graver Tank, 339 U.S. at 609).
Substitution of an ingredient known to be an equivalent to that required by the claim presents
a classic example for finding infringement under the doctrine of equivalents. Coming Glass
Works v. Sumitomo Elcc. U.S.A., Inc., 868 F.2d 1251, 1260 (Fed. Cir. 1989) (citing Graver

Tank, 339U.S. at 609). Interchangeability is auseful consideration when determining whether
two specific structures are equivalents. Rite-Hite Corp. v. Kelley Co., 819 F.2d 1120, 1125

(Fed. Cir. 1987) (citing Graver Tank, 339 U.S. at 609).
21. Thomas & Betts Corp. v. Litton Sys., 720 F.2d 1572, 1579 (Fed. Cir. 1983).

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DOCTRINE OF EQUIVALENTS

in C.R. Bard Inc. v. Kendall Co., put the "interchangeability" factor in
to perspective when it held that "interchangeability" is but one factor to be
considered in an equivalents analysis, and does not by itself establish equivalence
under the Graver Tank standard.22

2. Timing of Equivalency Review

In regard to timing, infringement by equivalents is determined at the
time of infringement, and not by what the inventor (or others skilled in the
art) knew when the patent was filed or issued." In other words, it is not
required that those skilled in the art knew of the asserted equivalent means
of performing the claimed function at the time the patent application was filed,
but that those skilled in the art know of the asserted equivalent means of
performing the claimed function at the time infringement takes place.24

Therefore, a partial variation in technique or an embellishment made possible
by post-patent technology, does not always allow the accused method or product
to escape the 'web of infringement. "2 '

3. The Additional Functions Defense

A common defense to the doctrine of equivalents is that the accused device
performs additional functions not found in the patented device. The Federal Circuit
has held that infringement under the doctrine of equivalents is not precluded merely
because the accused device performs functions in addition to those performed
by the claimed device.26 It is the limitations and functions of the invention
described in the claims, not the elements or functions of the accused device, that
establish the reference point for the doctrine of equivalents."

4. Limitations on the Doctrine of Equivalents

As mentioned earlier, the patent holder may be estopped from broadening
the scope of the claim beyond the literal meaning of its words.28 Three

22. C.R. Bard Inc. v. Kendall Co., 935 F.2d 280, 280 (Fed. Cir. 1991).
23. Atlas Powder Co. v. E.I. duPont de Nemours & Co., 750 F.2d 1569, 1581 (Fed.

Cir. 1984); Texas Instruments, Inc. v. United States Int'l Trade Comm'n, 805 F.2d 1558, 1563
(Fed. Cir. 1986).

24. Texas Instruments, 805 F.2d at 1563 (citing Atlas Powder Co., 750 F.2d at 1581).
SeealsoAmerican Hosp. Supply Corp. v. Travenol Labs., Inc., 745 F.2d 1, 8 (Fed. Cir. 1984).

25. Moleculon Research Corp. v. CBS, Inc., 872 F.2d 407,409-10 (Fed. Cir. 1989) (citing
Hughes Aircraft Co. v. United States, 717 F.2d 1351, 1365 (Fed. Cir. 1983)).

26. Insta-Foam Prods., Inc. v. Universal Foam Sys., 906 F.2d 698, 702 (Fed. Cir. 1990).
27. Id.
28. See cases cited supra note 16.

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IND. INT'L & COMP. L. REV.

frequently cited limitations of the doctrine of equivalents include: prosecution
history estoppel, prior art, and technological advances.

a. Prosecution History Estoppel

Prosecution history estoppel is an equitable tool for determining the
permissible scope of patent claims.29 Normally, in order to obtain the patent
grant, the patent applicant will make material representations to the Patent
and Trademark Office (PTO), in response to references cited by the PTO,
that in effect alter the scope of the patent claims. Typically these representations
reduce the scope of the patent in order to avoid the prior art. These material
representations are pertinent to the subsequent determination of the permissible
scope of the patent claim.3" Prosecution history estoppel will not allow the
patentee to recapture through equivalence certain coverage given up during
prosecution."

b. Prior Art

There can be no infringement under the doctrine of equivalents if the
asserted scope of equivalency would encompass the prior art. 2 The limitation
posed by the prior art is simply that the asserted range of equivalents may
not encompass the prior art at the very point at which the claims distinguish

29. Mannesmann Demag Corp. v. Engineered Metal Prods. Co., 793 F.2d 1279, 1284
(Fed. Cir. 1986).

30. Builders Concrete, Inc. v. Bremerton Concrete Prods. Co., 757 F.2d 255, 258 (Fed.
Cir. 1985).

31. Loctite Corp. v. Ultraseal Ltd., 781 F.2d 861, 870 (Fed. Cir. 1985); Jonsson v. Stanley
Works, 903 F.2d 812, 821 (Fed. Cir. 1990) (quoting Thomas & Betts Corp., 720 F.2d at 1579);
Mannesmann Demag Corp., 793 F.2d at 1284 (citing Thomas & Betts Corp., 720 F.2d at 1579
and Stewart-WarnerCorp., 767 F.2d at 1572). For example, "[w]hen an accused device is
the same as a disclosed embodiment, and claims covering the disclosed embodiment are rejected
and canceled, the yielded claim scope cannot be recovered in order to encompass the accused
device through the doctrine of equivalents." Diversitech Corp. v. Century Steps, Inc., 850
F.2d 675, 681 (Fed. Cir. 1988). In Dhersitech, the rejected claim was to a device with a coating
on all sides; the final claims recited a coating on top and sides only. The defendant put a
coating on the bottom and the patentee argued equivalency. Inasmuch as equivalence was
demonstrated in the specification, the Federal Circuit's refusal to accept this argument is clearly
grounded on estoppel. Although the claim was not amended, the broader claim from which
it depended was canceled. See also E.I. duPont de Nemours Co. v. Phillips Petroleum Co.,
849 F.2d 1430, 1438 (Fed. Cir. 1988), cert. denied, 488 U.S. 986 (1988); Hi-Life Products
Inc. v. American Nat'l Water-Mattress Corp., 842 F.2d 323, 325 (Fed. Cir. 1988).

32. Pennwalt Corp., 833 F.2d at 934 n. 1 (citing Loctite Corp., 781 F.2d at 870).

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DocTRam OF EQUIVALENTS

from the art." Discerning the range of equivalents "involves consideration
of what the prior art would have anticipated, 35 U.S.C. § 102, and what the
prior art would have made obvious, 35 U.S.C. § 103, when the patentee filed
the original application." '34 Whether an asserted range of equivalents would
cover what is already in the public domain, is a question of law."

The Federal Circuit has established a method for determining the limits
of claim coverage in view of prior art which in essence involves writing a
hypothetical claim covering the accused device and deciding whether it is
patentable over the prior art."

[1]t may be helpful to conceptualize the limitation on the scope
ofequivalents byvisualizing ahypothetical patent claim, sufficient
in scope to literally cover the accused product. The pertinent
question then becomes whether that hypothetical patent claim could
have been allowed by the PTO over the prior art. If not, then
it would be improper to permit the patentee to obtain that coverage
in an infringement suit under the doctrine of equivalents. If the
hypothetical claim could have been allowed, then the prior art is
not a bar to infringement under the doctrine of equivalents."

Thus, Wilson Sporting Goods teachesthatthe patentee bears the burden of showing
that the range of equivalents it seeks will not encompass the prior art.3

c. Technological Advances

It has always been thought that an "'embellishment' made possible by
technological advances may not permit the accused device to escape the 'web

33. Stewart-Warner Corp., 767 F.2d at 1572 (citing Thomas& Betts Corp., 720 F.2d
at 1580 and Hughes AircraftCo., 717 F.2d at 1362). It is well established that limitations
in a claim cannot be given a range of equivalents so wide as to cause the claim to encompass
anything in the prior art. Senmed, Inc. v. Richard-Allen Med. Indus., Inc., 888 F.2d 815,
821 (Fed. Cir. 1989) (citing Perkin-Elmer Corp., 732 F.2d at 900). Claims may not be enlarged
by equivalents to encompass the teachings of the prior art. Tandon Corp. v. United States
ITC, 831 F.2d 1017, 1026 (Fed. Cir. 1987) (citing Perkin-Elmer Corp., 732 '1.2d at 900).

34. We Care, Inc. v. Ultra-Mark Int'l Corp., 930F.2d 1567, 1571 (Fed. Cir. 1991) (vacating
the district court's preliminary injunction based on the likelihood of success in proving
infringement under the doctrine of equivalents because the district court failed to determine
whether the prior art would have made the range of equivalents given to the patent).

35. Wilson Sporting Goods Co. v. David Geoffrey & Assoc., 904 F.2d 677, 684 (Fed.
Cir. 1990), cert. denied, 498 U.S. 992 (1990).

36. Id
37. Id. See also, Insta-Foam Prods., 906 F.2d at 703-4.
38. Wilson Sporting Goods, 904 F.2d at 685.

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IND. INT'L & COMP. L. REv.

of infringement."' 39 Indeed, that has been suggested as one of the purposes
underlying the doctrine--to protect inventors from unanticipated equivalents.4"
But in Texas Instruments Inc. v. United States ITC, the court. held that where
extensive technological advances in all claimed functions result in multiple
departures from literal readability, the totality of change in the accused device
may be too much to support a holding of infringement.4 '

C. Purpose of the Doctrine of Equivalents

The doctrine of equivalents originated almost a century ago in the case
of Winans v. Denmead, 56 U.S. (15 How.) 330.42 Since that time, the doctrine
has been consistently applied by the Supreme Court and lower federal courts,
and continues today ready and available for utilization when the proper-
circumstances for its application arise. The doctrine of equivalents was judicially
devised to provide equity43 and is intended to be used "in situations where
there is no literal infringement but liability is nevertheless appropriate[,] to
prevent what is in essence a pirating of the patentee's invention." '44 The
Supreme Court in Graver Tank recognized the necessary role the doctrine
of equivalents plays in patent protection when it stated:

[C]ourts have also recognized that to permit imitation of a patented
invention which does not copy every literal detail would be to
convert the protection of the patent grant into a hollow and useless
thing. Such a limitation would leave room for-indeed
encourage-the unscrupulous copyist to make unimportant and
insubstantial changes and substitutions in the patent which, though
adding nothing, would be enough to take the copied matter outside
the claim, and hence outside the reach of the law .... Outright
and forthright duplication is a dull and very rare type of
infringement. To prohibit no other would place the inventor at
the mercy of verbalism and would be subordinating substance to
form. It would deprive him of the benefit of his invention and

39. Datascope Corp. v. SMEC, Inc., 776 F.2d 320, 326 (Fed. Cir. 1985) (quoting Hughes
Aircraft Co., 717 F.2d at 1365).

40. See Kinzenbawv. Deere & Co., 741 F.2d 383, 389 (Fed. Cir. 1984), cert. denied,
470 U.S. 1004 (1985).

41. Texas Instruments, 805 F.2d at 1571.
42. Graver Tank, 339 U.S. at 608.
43. Hughes Aircraft Co., 717 F.2d at 1361.
44. Hormone Research Found., Inc. v. Genentech, Inc., 904 F.2d 1558, 1564 (Fed. Cir.

1989) (quoting Loctite Corp., 781 F.2d at 870).

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DOCTRINE OF EQUIVALENTS

would foster concealment rather than disclosure of inventions, which
is one of the primary purposes of the patent system. 4S

To achieve this purpose, equivalency is judicially determined by reviewing
the content of the patent, the prior art, and the accused device, and essentially
redefining (broadening) the literal scope of the claims. Broadening the literal
scope of a claim, in essence, "constitutes a deviation from the need of the
public to know the precise legal limits of patent protection without recourse
to judicial ruling.",46 "To the extent that the doctrine of equivalents represents
an exception to the requirement that the claims define the metes and bounds
of patent protection," the doctrine is admissible only to serve its real purpose,
which is "to temper unsparing logic and serve the greater interest ofjustice."'47

The doctrine of equivalents essentially presents the courts with a difficult
dichotomy. On the one hand, claims must be particular and distinct so that
the public has fair notice of what the patentee and the PTO have agreed
constitute the metes and bounds of the claimed invention. Notice permits
other parties to avoid actions that infringe the patent and to design around
the patent. On the other hand, the patentee should not be deprived of the
benefits of his or her patent by competitors who appropriate the sense of the
invention while barely avoiding the literal language of the claims. Thus,
although designing around a particular patent is encouraged, piracy is not.
The doctrine of equivalents emerged to deal with this problem.4"

Some courts have doubted whether the doctrine of equivalents automatically
should be considered in every case where literal infringement is not present:

Application of the doctrine of equivalents is the exception, however,
not the rule, for if the public comes to believe (or fear) that the
language of patent claims can never be relied on, and that the
doctrine of equivalents is simply the second prong of every
infringement charge, regularly available to extend protection beyond
the scope of the claims, then claims will cease to serve their
intended purpose. Competitors will never know whether their
actions infringe a granted patent.4"

45. Graver Tank, 339 U.S. at 607.
46. Texas Instruments, 805 F.2d. at 1572. The court had previously cautioned against

expansion of the doctrine too far, to the point where patent counsel cannot rely at all on what
the claims recite when advising a client as to infringement. Great Northern Corp. v. Davis
Core & Pad Co., 782 F.2d 159, 166 (Fed. Cir. 1986).

47. Texas Instruments, 805 F.2d. at 1572 (foreshadowing a less expansive application
of the doctrine of equivalents in future cases).

48. London v. Carson Pirie Scott & Co., 946 F.2d 1534, 1538 (Fed. Cir. 1991).
49. Id.

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IND. INT'L & COMP. L. REv.

"Each case in which infringement by equivalents is asserted turns on its facts,
• . .and requires the trier of fact to balance the competing public policies
of avoiding a 'fraud on the patent"' with the public's need for reasonable
certainty as to the scope of the patent grant.50

In summary, application of the doctrine expands the right to exclude
"equivalents" of what is claimed. The doctrine of equivalents does not change
the scope of the patent protection as defined by the claims. The doctrine,
"by definition, involves going beyond any permissible interpretation of the
claim language; i.e., it involves determining whether the accused product is
'equivalent' to what is described by the claim language."'"

III. INTERNATIONAL PATENT PROTECTION AND THE ROLE

OF THE DOCTRINE OF EQUIVALENTS

The laws of a country relating to patent protection are generally concerned
with acts accomplished or committed in the country itself 2 Consequently,
a patent is effective only in the country that effected the grant.53 Therefore,
a patent owner desiring protection in several countries, must obtain a patent
grant in each country separately.54 Today, many American industries conduct
their business in the global marketplace. In order to protect their unique
products worldwide, these international companies pursue patent rights in
the foreign countries where they conduct business. Just as the doctrine of
equivalents is crucial in protecting patent rights in the United States, it is equally
important in international forums. Although the doctrine of equivalents is
applied in many international forums, it is not applied or interpreted
harmoniously. This lack of harmony in patent protection is just one of the
risks incurred by companies doing business internationally.

A. The European Community

One exception to the general rule that a patent is only effective in the country
issuing the grant is in the E.C., where the European Patent is recognized by all

50. Sun Studs, Inc. v. ATA Equip. Leasing, Inc., 872 F.2d 978, 987-8 (Fed. Cir. 1989)
(quoting Graver Tank, 339 U.S. at 608).

51. Wilson Sporting Goods, 904 F.2d at 684.
52. NEW YORK COUNTY LAWYERS ASS'N. COMM. ON PATENTS TRADEMARKS &

COPYRIGHTS, HANDBOOK ON PATENTS TRADEMARKS & COPYRIGHTS 89 (1982).
53. Id. at 89-90.

54. Id. at 90.

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DOCTRINE OF EQUIVALENTS

the E.C. Member States. Since the Treaty of Rome (E.E.C. Treaty)" came
into effect on January 1, 1958, the Member States of the E.C. have been striving
to establish a common market and coordinating their economic policies to promote
harmonious economic development throughout the Community. The establishment
of a common market has dramatically increased the economic opportunities available
to both Member States and foreign businesses. Along with the increase in economic
opportunities within the E.C. has come an increase in businesses competing for
the financial rewards of a growing E.C. market. As competition within the E.C.
continues to heighten between businesses actively involved in the E.C. market,
the patent protection afforded by each Member State becomes vitally important.

Recognizing the importance of harmonization of national patent laws
in the E.C., the Member States committed themselves to patent law
harmonization via the European Patent Convention (EPC)56 The EPC provides
that an inventor may apply for a European Patent at the European Patent Office
(EPO) in Munich, or at its branch in The Hague.57 After the EPO has
conducted a priority search and examined the application for originality and
capability of industrial use, the EPO may grant a European Patent.5 In the
event a European Patent is granted, the inventor is deemed to have acquired
a patent in each of the ratifying states59 for twenty years from the date of
application.6 ° The EPC reconciles a number of key substantive patent law
concepts in the ratifying states6' and provides for a central system to review
challenges to the application or patent.62 However, many aspects of the
European Patent continue to be governed by different national laws.63 A
key aspect of the EPC is that any infringement of a European Patent is handled
by special national courts set up in each Member State to settle patent
infringement issues."

55. Treaty establishingthe European Economic Community, Mar. 25, 1957, TREATIES
ESTABLISI-ENG THE EUROPEAN COMMuNrITES (Office for Official Publications of the European

Communities abr. ed., 1979).
56. Convention on the Grant of European Patents (European Patent Convention), Oct.

5, 1973, 13 I.L.M. 270 [hereinafter EPC]. The EPC came into force on March 1, 1979, and
strongly promotes the harmonization of patent rules. The Convention was signed by the then
nine Member States, as well as the five non-EC states. Most of the Member States and several
non-EC states have ratified it, so the EPC is effective throughout most of Western Europe.

57. Id. art. 75(l)(a).
58. Id. art. 52(1).
59. Id. art. 64(l).
60. Id. art. 63(1).
61. Id. art. 52-74.
62. Id. art. 15-22.
63. Id. art. 74.
64. Patent LitigationBefore European National Courts; Today And Tomorrow, Patent,

Trademark & Copyright Law Daily (BNA) 6 (July 7, 1992).

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IND. INT'L & COMP. L. REV.

In order to help the national courts determine infringement disputes
uniformly, Article 69 of the EPC provides a guideline for interpreting the
scope of protection conferred by a European Patent. 6

' The Protocol on the
Interpretation of Article 69 of the EPC (Protocol) calls for an intermediate
standard that "combines a fair protection for the patentee with a reasonable
degree of certainty for third parties." The purpose of the Protocol is to
strike a balance between two fundamental extremes: strict literal interpretation
and broad guidelines. The Protocol, having been officially adopted by all
members of the EPC,67 should have pulled followers of the extremes to a
common, harmonized, middle ground of "fair protection" and "reasonable
certainty." Article 69 of the EPC and the Protocol, in theory, should allow
for the use of the doctrine of equivalents in EPC patent interpretation. The
freedom from strict literal interpretation, which the equivalents doctrine provides,
should inhibit a tumbling into open-ended guidelines that might chill third
parties fearing extensive infringement liability.

A good example of how the Protocol has not fulfilled its objective of
pulling the Member States to a common, harmonized, middle ground of "fair
protection" and "reasonable certainty" is clearly demonstrated in the Epilady
litigation conducted in the United Kingdom and West German national courts.

65. EPC, supra note 56, art. 69(1). Article 69(l) states: "The extent of the protection
conferred by a European patent or a European patent application shall be determined by the
terms of the claims. Nevertheless, the description and drawings shall be used to interpret the
claims." Id.

66. Protocol on the Interpretation of Article 69 of the Convention, Oct. 5, 1973, 13 l.L.M.
270 [hereinafter Protocol]. The Protocol reads as follows:

Article 69 should not be interpreted in the sense that the extent of the protection
conferred by a European patent is to be understood as that defined by the strict,
literal meaning of the wording used in the claims, the description and drawings
being employed only for the purpose of resolving an ambiguity found in the
claims. Neither should it be interpreted in the sense that the claims serve only
as a guideline and that the actual protection conferred may extend to what, from
a consideration of the description and drawings by a person skilled in the art,
the patentee has contemplated. On the contrary, it is to be interpreted as defining
a position between these extremes which combines a fair protection for the patentee
with a reasonable degree of certainty for the third parties.

id. at 348.
67. David Perkins, Foreign Principles OflntellectualPropertyAntitrust: The EEC, in

INTELLECTUAL PROPERTY/ANTITIRUST 279, 317 Practicing Law Institute, 1992). All EC countries,
except Ireland, and all EFTA countries except Finland and Iceland have ratified the EPC.
EC Member States have also amended their national laws to harmonize them with the EPC,
the exception again being Ireland. Id.

[Vol. 5:2



DOCTRINE OF EQUIVALENTS

A°

j\%I !. -'.\"
I, 1 I

FIG. I FIG. 2

* Diagram reprinted as found in Improver Corp. & Others v. Remington
Consumer Products Ltd. & Others, [1990] F"S.R. 181, 185-186 (Eng. Ch.
1989) (reprinted in 21 INT'L. REV. OF INDUS. PROP. & COPYRIGHT LAW 680,
681 (1990)).

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DOCrRINE OF EQUIVALENTS

IV.THE EPILADY CONTROVERSY

A. Epilady Story

In July of 1983 two Israeli men filed a patent application with the EPO.68

They were seeking a patent for their invention of a device that removes body
hair from the arms and legs of women for cosmetic purposes. The European
patent, Number 0101656,69 was granted in November 198670 for the depilatory
device. The European Patent was valid in a considerable number of Contracting
States, including the United Kingdom and West Germany." Improver
Corporation [hereinafter Improver], the owner of the patent by assignment,
marketed the depilatory device under the name "Epilady"."

The Epilady, illustrated in Figures I and 2, consisted of an electric motor
(4,4') in a hand-held housing (2) to which was attached a helical steel spring
(24) held by its end and stiffened by a guide wire to form a loop.73 The
arcuate form of the spring caused gaps between the windings to open on the
convex side and close on the concave side.74 When the spring was rotated
at high speed and held close to the skin, hairs entered the gaps on the convex
side and were gripped between the windings as the rotational movement brought
them around to the concave side." The effect was to pluck the hair from
the skin.76

Marketing of the Epilady began in 1986 and was an enormous commercial
success." In the first two years over 5.8 million devices were made, generating
sales in excess of $340 million dollars.78 Based on the quick success of
the Epilady, Improver and licensed manufacturers and distributors soon found
themselves facing a variety of imitators.79 "The most notorious alleged in-
fringement involved a competing product manufactured for and sold by

68. Sanford T. Colb, The Epilady Hair Remover Litigation, in GLOBAL INTELLECTUAL

PROPERTY SERIES 1993, at 107, 109 (PLI Patents, Copyrights, Trademarks, and Literary Property
Course Handbook Series No. G4-3907, 1993).

69. Improver Corp. & Others v. Remington Consumer Products Ltd. & Others, [ 1990]
F.S.R. 181, 184 (Eng. Ch. 1989).

70. Improver Corp. v. Remington Consumer Products Ltd., [1989] R.P.C. 69,71 (Eng.
C.A. 1988).

71. Id.
72. Id. at 72.
73. Improver Corp. & Others, [1990] F.S.R. at 184.
74. Id.
75. Id.
76. Id.
77. Id.
78. Id.

79. Colb, supra note 68, at 110.

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IND. INT'L & COMP. L. REv.

Remington Consumer Products [hereinafter Remington], an American-based
company known for its line of electric shaving products.""0

Remington produced a rival device known as the "Smooth and Silky"."'
This device also comprised of an electrical motor and a hand held housing.' 2

But instead of using a metal helical spring, the element attached to the motor
and used to extract the hair was a cylindrical rod of elastic synthetic rubber
held by its ends to form an arc subtending about 60 degrees.83 A number
of parallel radial slits were cut into the rubber. 4 The arcuate form of the
rod caused the slits to open on the convex side and to be pressed together
on the concave side. When the rod was rotated at high speed and held close
to the skin, hairs entered the gaps on its convex side and were gripped between
the walls of the slits as the rotational movement brought them around to the
concave side. 5 The effect was to pluck the hair from the skin. 6

When the "Smooth and Silky" entered the U.K. and German markets,
Improver sought a preliminary injunction in both the U.K. and Germany.87

The application before the English Patents Court was dismissed on the basis
of no arguable case on infringement.8 In contrast, a preliminary injunction
was granted by the German District Court (Landgericht of Dusseldorf). 9

When the decision of the English Patents Court was appealed, the Court of
Appeals-having regard for the findings of the German District Court-held
there was an arguable case for infringement and granted the preliminary
injunction ordering the English Patents Court to reconsider the claim.9" In
the meantime, the German Court of Appeals (Oberlandesgericht), having regard
for the initial decision of the English Patent Court, discharged the preliminary
injunction granted by the German District Court.9' When the Epilady dispute
was decided on the merits in the German District Court, it found that the

80. Id
81. Improver Corp. & Others, [1990] F.S.R. at 181.
82. Id. at 186.
83. Id.
84. Id

85. Id.
86. Id.
87. Improver Corp., [1989] R.P.C. at 71; Improver Corp. & Sicommerce AGv. Remington

Products Inc., Case No. 2 U 181/88 (OLG 1988), translated in 21 INT'L. REv. OF INDUS. PROP.
& COPYRIGHT LAW 572, 573 (1990).

88. Improver Corp., [1989] R.P.C. at 73.

89. Improver Corp. & Sicommerce AG v. Remington Products Inc., 21 INT'L. REV. OF
INDUS. PROP. & COPYRIGHT LAW 572, 573.

90. Improver Corp., [19891 R.P.C. at 81.
91. Improver Corp. & SicommerceAG v. Remington Products Inc., 21 INT'L. REv. OF

INDUS. PROP. & COPTRIGHT LAW 572, 579.

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DOCRINE OF EQUIVALENTS

"Smooth and Silky" infringed on the Epilady patent.92 In contrast, at trial
before the English Patents Court, the "Smooth and Silky" was held not to
have infringed on the Epilady patent.93

The Epilady dispute serves to illustrate the substantive contradictions
among the national approaches in regard to patent claim interpretation. The
most disconcerting aspect of the Epilady litigation is that both the German
and English courts interpreted the same patent, operated under an approximately
identical set of facts, utilized a uniform standard of interpretation-Protocol
on the Interpretation of Article 69 of the EPC-and still managed to come
up with two polar decisions.

The remainder of this note will closely analyze the final decisions of
the Epilady dispute in both the German and English courts. A comparison
will be conducted to distinguish the reasons causing the inconsistent decisions
and a hypothetical U.S. decision will be proposed applying U.S. patent law
to the facts of the Epilady dispute. Lastly, the current draft of the Patent
Harmonization Treaty-intended to harmonize some of the patent laws throu-
ghout the world-will be analyzed to see whether it might have helped prevent
the inconsistent decisions that the Epilady dispute generated.

B. UK Epilady Decision

When the English Patents Court considered the merits of the Epilady
dispute, Justice Hoffmann decided the question of infringement turned upon
a short but undoubtedly difficult point of construction. 9 This difficult point
of construction was whether the rubber rod is a "helical spring" as that expressed
in the claims of the Improver European Patent.95 Justice Hoffmann said
that the proper approach to the interpretation of patents registered under the
Patents Act 197796 was explained by Lord Diplock in Catnic Components

92. Improver Corp. & Sicommerce AG v. Remington Products Inc., CaseNo. 2 U 27/89
(OLG 1991) translated in 24 INT'L. REv. OF INDUS. PROP. & COPYRIGHT LAW 838, 839 (1993).

93. Improver Corp. & Others, [1990] F.S.R. at .195.

94. Id. at 187.
95. Id.

96. Section 130(7) of the 1977 Patents Act declares that certain provisions of the Act,
including section 125, "are so framed as to have, as nearly as practicable, the same effects
in the United Kingdom as the corresponding provisions of the European Patent Convention
.... Patents Act, 1977, ch. 37 § 130(7).
Subject I of Section 125 of the 1977 Patents Act, which corresponds to Article 69 of the EPC
provides:

(1) For the purposes of this Act an invention for a patent for which an application
has been made or for which a patent has been granted shall, unless the context
otherwise requires, be taken to be that specified in a claim of the specification

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IND. INT'L & CoMP. L. REv.

Ltd. v. Hill & Smith Ltd., [1982] R.P.C. 183, 242 (H.L. 1980). 97 Justice
Hoffmann summarized Lord Diplock's interpretation approach saying that
the language of the claim should be given a "purposive" and not necessarily
a literal construction.9 Justice Hoffmann in applying the "purposive"
construction technique said that when the issue is whether a variant" embodied
in an alleged infringing product is within the claim's language as properly
interpreted, the court should ask itself three questions: (1) does the variant
have a material effect upon the way the invention works; (2) would the fact
that the variant has no material effect upon the way the invention works have
been obvious at the date of publication of the patent to a reader skilled in
the art; and (3) would the reader skilled in the art nevertheless have understood
from the language of the claim that the patentee intended that strict compliance
with the primary meaning was an essential requirement of the invention."'

of the application or patent, as the case may be, as interpreted by the description
and any drawings contained in that specification, and the extent of the protection
conferred by a patent or application for a patent shall be determined accordingly.

Id. § 125(1).
Subject (3) of Section 125 declares:

The Protocol on the Interpretation of Article 69 of the European Patent Convention
(which Article contains a provision corresponding to subsection (1) above) shall,
as for the time being in force, apply for the purposes of subsection (1) above
as it applies for the purposes of that Article.

Id. § 125(3).
97. Improver Corp. & Others, [1990] F.S.R. at 187. Lord Diplock's description in Catnic

Components of how a patent specification should be construed, particularly with regard to
what is and what is not to be regarded as an essential integer (element), as follows:

A patent specification should be given a purposive construction rather than a
purely literal one derived from applying to it the kind of meticulous verbal analysis
in which lawyers are too often tempted by their training to indulge. The question
in each case is: whether persons with practical knowledge and experience of
the kind of work in which the invention was intended to be used, would understand
that strict compliance with a particular descriptive word or phrase appearing in
a claim was intended by the patentee to be an essential requirement of the invention
so that any variant would fall outside the monopoly claimed, even though it could
have no material effect on the way the invention worked.

Catnic Components Ltd. v. Hill & Smith Ltd., [1982] R.P.C. 183, 242 (H.L. 1980).
98. Improver Corp. & Others, [1990] F.S.R. at 187.
99. It can be inferred that since Justice Hoffmann applies the three question analysis

in his opinion that he agrees with Justice Falconer that the rubber rod is not a "helical spring"
but a variant ("mechanical equivalent") of the "helical spring!' described in the Improver European
Patent.

100. Improver Corp. & Others, [1990] F.S.R. at 187.

[Vol. 5:2



DOCTRINE OF EQUIVALENTS

1. Justice Hoffnann's Three Question Analysis

a. Question (1): Does the variant have a material effect upon the
way the invention works?

If the variant has a material effect upon the way the invention works,
the variant is outside the claim and there is no infringement.'' If the variant
does not have a material effect upon the way the invention works, then the
second question of Justice Hoffmann's three prong test must be addressed.
Justice Hoffmann discussedtwo important guidelines to consider in answering
question one. First, a variant is a feature embodied in the alleged infringing
product which is not within the literal or contextual meaning of a descriptive
word or phrase in the claim.0 2 Second, whether the variant would make
a material difference to the way the invention worked is a question of fact
and not a question of construction; although it cannot be sensibly answered
without reference to the patent. 0 3

Justice Hoffinann stated the answer to the first question "depends upon
the level of generality at which one describes the way the invention works"' 4

and "that the right approach is to describe the working of the invention at
the level of generality with which it is described in the claim of the patent."'0 5

Remington's expert witness attempted to show the following four ways in
which the rubber rod used in the "Smooth and Silky" materially effected the
way the "Smooth and Silky" worked: (1) the gripping pressure of the rubber
rod is one-third of Epilady (i.e. less broken hairs); (2) the rubber rod has one-
fourth the number of slits and the slits themselves are discontinuous (i.e. pulls
less hair therefore less painful); (3) the slits in the rubber rod close at earlier
point and therefore grip shorter hairs better; and (4) the rubber rod doesn't
have a hollow core to trap hairs as does the "Epilady."' 6 Justice Hoffmann
after considering the expert witness's testimony decided that the rubber rod
works in the same way as the helical spring and the differences Remington's
expert described were not material (i.e., the rubber rod is an equivalent to
the helical spring).'0 '

101. Id.
102. Id.
103. Id. at 188.
104. Id. at 189.
105. Id. at 190.
106. Id. at 189-90.
107. Id. at 190.

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IND. INT'L & COMP. L. REv.

b. Question (2): Would the fact that the variant has no material effect
upon the way the invention works have been obvious at the date
of publication of the patent to a reader skilled in the art?

If it would not have been obvious at the date of publication of the patent
to a reader skilled in the art that the variant has no material effect upon the
way the invention works, the variant is outside the claim and there is no
infringement.'0 8 But, if at the date of patent publication it would have been
obvious to a reader skilled in the art that the variant has no material effect
upon the way the invention works, the third question must be considered.0 9

Justice Hoffmann describes two essential guidelines with respect to the second
question: first, he says that question two is a question of fact;"'and second,
question two supposes that the person skilled in the art is told of both the
invention and the variant and asked whether the variant would obviously work
in the same way."'

In considering this question, both Improver and Remington presented
expert testimony. Experts for both sides agreed that it would have been obvious
that any rod which had the qualities of the "helical spring" in sufficient degree
and did not have other defects, would in principle work in the same way as
the "helical spring," and that the rubber rod embodied in the "Smooth and
Silky" plainly belonged to that class. 12 Accordingly, Justice Hoffmann
held that since the experts agreed that a person skilled in the art would have
obviously understood that the rubber rod would work in the same way as
the "helical spring," the third question must be considered in order to determine
infringement.1 3

c. Question (3): Would the reader skilled in the art nevertheless
have understoodfrom the language of the claim that the patentee
intended that strict compliance with the primary meaning was
an essential requirement of the invention?

Rephrasing this question as it applies to the Epilady dispute, the question
asks: would a reader, skilled in the art, have understood the patentee to have
intended to confine his claim to the literal meaning of "helical spring." If
so, the rubber rod (the variant) is outside the claim and there is no

108. Id. at 187.
109. Id.
110. Id. at 188.
111. Id. at 190.
112. Id.
113. Id. at 190-1.

[Vol. 5:2



DOCTRINE OF EQUIVALENTS

infringement." 4  A negative answer to this question would lead to the
conclusion that the patentee was intending the phrase, "helical spring," to
have not a literal but a figurative meaning denoting a class of things which
included variants (such as Remington's rubber rod) and the literal meaning
(helical springs), the latter being perhaps the most perfect, best known or striking
example of the class."5

Justice Hoffmann stated that question three raises the question of
construction and Lord Diplock's formulation makes it clear that on this question
the answers to the first two questions are not conclusive. "Even a purposive
construction of the language of the patent may lead to the conclusion that
although the variant made no material difference and this would have been
obvious at the time [to a person skilled in the art], the patentee for some reason
was confining his claim to the [literal] meaning and excluding the variant." ' 6

Justice Hoffmann in answering the third question considered the views
of two expert witnesses.'17 Dr. Sharp, Improver's expert witness skilled
in the art, stated:

[I]t would have been obvious to me that all the inventor wanted
a helical spring for was as a convenient rotating bent beam in which
slits formed by the adjacent windings would open and close as
it rotated. It would then have been equally obvious to me that
he could have not intended to exclude equivalents like the [rubber]
rod. . . . [I]n thinking of equivalents I feel driven by the last
paragraph of the specification before the claims [the equivalents
clause] to think that the inventor was trying to make me think of
equivalents for the helical spring ... 

114. Id. at 187.
115. Id. at 187-88.
116. Id. at 188.
117. Id. at 190-93.
118. Id. at 191. The description of the Improver European Patent ends with the following

general statement, which the court refers to as the "equivalents clause":
It will be evident to those skilled in the art that the invention is not limited to
the details of the foregoing illustrative embodiments, and that the present invention
may be embodied in the other specific forms without departing from the essential
attributes thereof, and it is therefore desired that the present embodiments be
considered in all respectsas illustrative andnot restrictive, reference being made
to the appended claims, rather than to the foregoing description, and all variations
which come within the meaning and range of equivalency of the claims are
therefore intended to be embraced therein.

Id. at 185.

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IND. INT'L & COP. L. REV.

Dr. Laming, Remington's expert witness skilled in the art, stated:

My opinion is that there is no way of interpreting . . .
[Improver's] specification such that anything other than a helical
spring is intended....

I have now read the European Patent several times and it is clear
that nothing other than a helical spring is referred to. If there were
alternatives to a helical spring which the inventor or draftsman
had in mind he did not indicate anywhere that such alternative
might be used....

If .... [Improver's] specification contained anywhere such words
as "or any other configuration of an elastic member or members
whereby rotation of the member or members causes a spread apart
orientation at one position and a pressed together orientation at
another position or point in the cycle" then at least one might be
led to think about alternatives to the helical spring.1 9

In regard to the equivalence clause contained in the Improver patent, Dr. Laming
said:

It is true that [in the equivalents clause] reference is made to
embodiment 'in other specific forms' and it asks there for reference
to be made 'to the appended claims rather than the foregoing
description.' But what follows is a series of claims in which the
variations are all on such matters as the angle subtended by the
arcuate portion, the degree of opening of the windings, various
mechanical drive options, and different surface speeds. A constant
feature of all the claims is the specification of a helical spring which
itself is the only type of element mentioned in the text of the
specification and shown in the figures.2

Justice Hoffmann's opinion of the expert testimony was that the difference
between the experts depends on how one construes the equivalents clause
contained in the Improver patent.121 Justice Hoffmann believed the first
part of the clause, which is not at issue in this case, meant that the description
should not be construed to restrict the meaning of the language used in the

119. Id. at 192-93.
120. Id. at 193.
121. Id.

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DOCTRINE OF EQUIVALENTS

claim. "'22 Justice Hoffmann went on to say that the words "and all variations
which come within the meaning and range of equivalency of the claims are
therefore intended to be imbraced therein" meant no more than to construe
the claims in accordance with Catnic Components Ltd. and the Protocol.'23

Justice Hoffmann after considering the testimony of the expert witnesses,
answered question three saying: "I do not think that the 'helical spring' can
reasonably be given a wide generic construction and I accept Dr. Laming's
reasons for thinking that a skilled man would not understand it in this
sense."' 24 In summary, Justice Hoffmann held that even though the differences
between the rubber rod and the helical spring are not material (i.e., the rubber
rod and helical spring work in the same way), and that a person skilled in
the art would obviously understand the rubber rod works in the same way
as the helical spring, there is nevertheless no infringement since a reader, skilled
in the art, would interpret the patentee as confining his claim to the literal
meaning of helical spring.

C. German Epilady Decision

The German District Court in deciding the Epilady controversy applied
a two question test.'25 The first question was whether the rubber rod had
the identical effect of the helical spring (i.e., was the rubber rod an equivalent
of the helical spring), and the second question was whether the rubber rod
would have been an obvious equivalent to a person skilled in the art, looking
at the descriptions prospectively from the time the patent was issued.'26

1. The German District Court's Two Question Analysis

a. Question (1): Does the rubber rod have the identical effect of
the helical spring?

The German District Court in determining whether the Remington
depilatory device infringed on Improver's European patent began its inquiry
by using claim one of the patent to determine the patent's "teaching.' 1 27

122. Id.
123. Id.
124. Id.
125. Improver Corp. & Sicommerce AG v. Remington Products Inc., 24 INT'L. REV. OF

INDUS. PROP. & COPYRIGHT LAW 838, 842.
126. Id.
127. Id. at 839. Claim one reads as follows:

An electrically powered depilatory device comprising: a hand held portable housing
(2); motor means (4,4') disposed in said housing; and a helical spring (24)

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IND. INT'L & COMP. L. REV.

The German court identified seven features that it believed were the essential
characteristics of the Epilady depilatory device defined in claim one.'28 Similar
to the method used to determine infringement in the United States,'29 the
German court required that in order to find infringement, each of the seven
features must be embodied by the Remington depilatory device either literally
or by equivalence. 3

The German court subsequently held that the Remington depilatory device
fulfilled features one and two literally, but said that features three through
seven were not fulfilled literally since Remington's depilatory device did not

comprising a plurality of adjacent windings arranged to be driven by said motor
means in a rotational sliding motion relative to skin bearing hair to be removed,
said helical spring (24) including an arcuate hair engaging portion arranged to
define a convex side whereat the windings are spread apart, and a concave side
corresponding thereto whereat the windings are pressed together, the rotational
motion of the helical spring (24) producing continuous motion of the windings
from a spread apart orientation at the convex side to a pressed together orientation
at the concave side and for engagement and plucking of hair from the skin of
the subject, whereby the surface velocities of the windings relative to the skin
greatly exceeds the surface velocity of the housing relative thereto.

Id. at 838.
128. Id. at 840. The seven features comprising the teaching of claim one according to

the Court are as follows:
The electrically powered depilatory device comprises
1. a hand held portable housing,
2. motor means positioned in said housing,
3. a helical spring comprising a plurality of adjacent windings,
4. the windings are arranged to be driven by said motor means in rotational sliding

motion relative to skin bearing hair to be removed,
5. said spring includes a hair engaging portion which

a) is arcuate,
b) defines a convex side whereat the windings are spread apart and
c) defines a concave side corresponding to said convex side whereat the windings
are pressed together,

6. the rotational motion of the spring produces a continuous motion of the windings
from a spread apart orientation at the convex side to a pressed together orienta-
tion at the concave side and for engagement with the hair and for plucking
of hair from the skin of the subject,

7. the surface velocity of the windings relative to the skin greatly exceeds the surface
velocity of the housing relative thereto.

Id.
129. To establish infringement of a patent every limitation set forth in a claim must be

found in the accused product or process exactly or by a substantial equivalent. Johnston v.
IVAC Corp., 885 F.2d 1574, 1581 (Fed. Cir. 1989).

130. Improver Corp. & Sicommerce AG v. Remington Products Inc., 24 INT'L. REV. OF
INDUS. PROP. & COPYRIGHT LAW 838, 841 (1993).

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DOCTRINE OF EQUIVALENTS

feature a helical spring per se.' However, the German court explained
that the "motor-driven rubber roll is... a replacement means equivalent to
the coil spring of the patent," and that features three through seven were given
in equivalent form.'32 The German court concluded its inquiry into the
first question when it stated that it had no doubt the rubber rod was an
equivalent based on the fact that the rubber rod "is identical in effect to a
device making use of the wording of claim 1 of the patent in suit."'33 Since
the German court did not find that the Remington depilatory device literally
embodied features three through seven, it noted that a second inquiry, in regard
to the obviousness of equivalency, must be conducted since infringement would
ultimately be based on equivalency.'34

b. Question (2): Whether the rubber rod would have been an obvious
equivalent to a person skilled in the art, looking at thg descriptions
prospectively from the time the patent was issued?

According to the German court, in order to find infringement by
equivalents, not only does the accused embodiment have to be an equivalent
(i.e., have identical effect), but a person skilled in the art-applying the
professional knowledge at his disposal at the time the patent was issued and
based on the consideration progressing from the meaning of the patent
claims-must be able to detect the modified means used in the disputed
embodiment as being identical in effect as a solution to the problem underlying
the invention.'35  The German court stated that this inquiry into the
determination of infringement by equivalency is intended to align German
patent law with Article 69(1) of the EPC and the Protocol. 13 6

In answering the second question, the German court was convinced that
a person skilled in the art---owing to the content of the claims of the Improver
patent-was capable of arriving at the disputed embodiment.'37 The German
court's starting point for this conclusion was that a person skilled in the art
would recognize by virtue of his professional knowledge that the helical spring
described in the Improver patent is used contrary to its common application
(as an mechanical energy buffer). 3 '

131. Id.
132. Id.

133. Id.
134. Id. at 842.
135. Id.
136. Id.
137. Id.

138. Id. at 843.

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IND. INT'L & COMP. L. REv.

[A] person skilled in the art ... will easily recognize that the coil
spring is only proposed for the reason that it is an elastic cylindrical
body which may be quickly rotated in the arcuate state and, above
all, for the reasons that it features... means that stretch the surface
of the body to form gaps at the convex side, while at the concave
side they result in clamping areas with the help of which the hairs
that entered the gaps may be clamped and plucked.'39

The court concluded that a person skilled in the art-looking at the descriptions
prospectively at the time the patent was issued-would interpret the words
"helical spring" not as a spring per se, but as a cylinder-shaped elastic element
with gaps, and therefore if the patent conveyed this knowledge, it would be
obvious to a person skilled in the art to use an elastic cylindrical rod with
slits, as usedrin the Remington depilatory device, as a hair plucking element. 40

Such an atypical use of the spring (as opposed to its conventional use as a
mechanical energy buffer) seemingly justified the broad interpretation of the
words "helical spring" used in claim one of the Improver patent.

In conclusion, the German court held that the rubber rod is identical
in effect to a "helical spring" disclosed in the Improver patent, and would
also be considered as an obvious equivalent to the "helical spring" by a person
skilled in the art orientating himself to the meaning of the patent claims, with
the help of findings available to him due to his professional knowledge. Since
the Remington depilatory device fulfilled features one and two literally and
features three thriough seven by equivalents, the German court found there
was infringement of the Improver European Patent by Remington's depilatory
device. 41

D. Implications Of The Variances Between The UK And German Decisions

While there is agreement between the English and German courts as
to the continued existence of the doctrine of equivalents, the application of
the doctrine differs. The principle difference between the German and English
approaches to claim interpretation is embodied in the third question of the
English Patent Court's equivalency analysis which is, in effect, an exception
to the doctrine of equivalents.'42 - The third question can in certain circum-
stances limit the court's interpretation of the claim to the strict literal meaning
of the claim's words. Justice Hoffmann believed that the third question is

139. Id.
140. Id.
141. Id. at 844.
142. Id. at 867-68.

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DocrINE OF EQUIVALENTS

a question to be asked in all cases of infringement by equivalence.' He
also emphasized the importance of the third question when he stated that the
first two questions were merely questions of fact which served to provide
the background against which the third question should be asked.'"

The third question asked by Justice Hoffmann is the reason the Epilady
dispute was decided differently in the U.K. than in Germany. For after having
answered variations of Justice Hoffmann's first two questions in favor of
Improver, the German court treated these answers as concluding the matter.
In direct contrast, while answering the first two questions in favor of Improver,
Justice Hoffmann found it necessary to ask the third question, on which basis
he found for Remington.

The principle difference in claim interpretation between the German
court and the English Patents Court-posed by Justice Hoffmann's third
question-raises two points. First, this difference suggests that the scope of
protection offered by a patent in the U.K. will be less than in Germany.'45

The reduction in scope of protection is brought about when the third question
forces the court to limit the scope of the claim to the strict literal meaning
of the claim's words. Second, since both the English and German decisions
were based upon Article 69 of the EPC and the Protocol on Interpretation,
these decisions reflect not only a different approach to patent infringement,
but also a different understanding of the nature of the Protocol itself.'46

Given the importance of claim interpretation in patent law, these differences
suggest a potential barrier to the harmonization of patent laws of the Member
States of the EPC. 147

The World Intellectual Property Organization (WIPO) recognized the
problems associated with inconsistent claim interpretation and the application
of the Protocol. In an effort to resolve these problems, the Committee of
Experts on the Harmonization of Certain Provisions in Laws for the Protection
of Inventions (Committee of Experts), drafted Article 21 of the Patent
Harmonization Treaty to harmonize the doctrine of equivalents worldwide
during the second part of the eighth session in Geneva, from October 29 to
November 9, 1990.'

143. Improver Corp. & Others v. Remington Consumer Products Ltd. & Others, [ 1990]
F.S.R. 181, 188 (Eng. Ch. 1989).

144. Id.
145. Improver Corp. v. Remington Consumer Products Ltd., 21 INT'L. REV. OF INDUS.

PROP. & COPYRIGHT LAW 860, 868 (1990).
146. Id.
147. Id
148. The Patent Harmonization Treaty is currently only in draft form. Article 21 is based

on the EPC's Protocol but goes on to give definitions of equivalence. Article 21 is reprinted
in 30 INDUS. PROP. 118, 127 (1991). The Patent Harmonization Treaty is discussed in Part
V of this note.

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IND. INT'L & COMP. L. REv.

E. Hypothetical Epilady Decision: Applying the US. Doctrine of Equivalents

In the United States, the doctrine of equivalents permits a finding of
direct infringement if the accused device performs substantially the same
function in substantially the same way to obtain substantially the same
result."'49 In applying the doctrine of equivalents it is important to remember
that the doctrine does not focus on the invention as a whole but on each element
of the claim. 50 Therefore, a finding of infringement requires the patentee
to show the presence of every essential element or its substantial equivalent
in the accused device.

In the Epilady controversy the determination of infringement was
contingent upon whether the elastic rubber rod used in the Remington depilatory
device is a substantial equivalent of the "helical spring" described in claim
one of the Improver patent. According to U.S. patent law, for the rubber
rod to be an equivalent of the helical spring all three prongs of the equivalency
test-function, way, and result-must be met.'' In the Epilady dispute
the function and result prongs of the equivalents test are easily met. First,
the rubber rod performs substantially the same function as that of the helical
spring, that is, the trapping of hairs for depilatory removal. Likewise, the
result of the helical spring and the rubber rod are substantially the same, that
is, the clamping and plucking of the hairs. The way component of the
equivalency test is not so easily determined.

The way in which the helical spring performs is best described as follows:
the arcuate form of the spring causes the gaps between the windings to open
on its convex side but to be pressed together on the concave side and when the
spring is held closely to the skin and rotated, the hairs enter the gaps on its convex
side and are gripped between the windings as the rotational movement brings
the hairs around to the concave side. In all likelihood, a federal district court
would hold that the elastic rubber rod performs in substantially the same way
as the helical spring described in the Improver patent. The rubber rod, like the
helical spring, when held in an arcuate position, deforms, causing gaps between
the parallel slits in the rubber rod to open on its convex side but to be pressed
together on the concave side. Also, in virtually the same manner as the helical
spring, when the rubber rod is held closely to the skin and rotated, the hairs enter
the gaps on its convex side and are gripped between the parallel slits as the rota-
tional movement brings the hairs around to the concave side. Based on this analysis,
the rubber rod performs substantially the same way as the helical spring.

149. See supra part lI.B.

150. Pennwalt Corp. v. Durand-Wayland, Inc., 833 F.2d 931,935 (Fed. Cir. 1987), cert.

denied, 485 U.S. 961, 1009 (1988).

151. Universal Gym Equip., Inc. v. ERWA Exercise Equip. Ltd., 827 F.2d 1542, 1548

(Fed. Cir. 1987).

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DOCTRINE OF EQUIVALENTS

Even though it appears that all three components of the equivalency
test are met, the patent holder may be estopped from broadening the scope
of the claim beyond the literal meaning of the words." 2 The two most likely
barriers preventing a finding of equivalence in the Epilady dispute are the
limitations posed by prior art and prosecution history estoppel. There can
be no infringement under the doctrine of equivalents if the asserted scope
of equivalency would encompass the prior art.'53 Nor can the coverage
given up during patent prosecution with the PTO be recaptured through
equivalence.'54

Determining the coverage of protection given up during prosecution
of the Improver patent is beyond the scope of this note,'" but an analysis
ofthe prior art limitation is possible because the prior art is disclosed in the
Improver patent. 156 The Improver patent cites six other patents as comprising
the prior art.'57 Each of these patents concerns depilatory devices.'58

Four involve manually operated helical springs.'"9 Three of the four manually
operated devices capture the hair by compressing the spring in a tweezer like
fashion and jerking the hairs out of the skin. 6

1 The other manually operated
device engages and grips the hairs in the same manner as does the Improver
device, but the specification is unclear if the same rotational motion removes
the hairs or if the hairs must be removed by moving the device away from
the skin. 6 ' The remaining two patents describe power-operated depilatory
devices that are quite different in comparison to the Epilady.' 62  One of
the power-operated depilatory devices uses a pair of rotating discs instead
of a rotating helical spring. 63 The other uses a helical spring, but the spring
is reciprocatingly compressed (in contrast to being held in an arcuate form
and rotated), extended, and intermittently rotated by an electrically driven

152. See supra part II.B.

153. Pennwalt Corp., 833 F.2d at 934 n. I (citing Loctite Corp. v. Ultraseal Ltd., 781
F.2d 861, 870 (Fed. Cir. 1985)).

154. Prosecution history estoppel will not allow the patentee to recapture through equivalence
certain coverage given up during prosecution. Loctite Corp., 781 F.2d at 870.

155. A record of the Epilady European Patent prosecution history was not available to
the author.

156. Improver Corp. & Others v. Remington Consumer Products Ltd. & Others, [1990]
F.S.R. 181, 184 (Eng. Ch. 1989).

157. Id.
158. Id.
159. Id.
160. Id.
161. Id.
162. Id.
163. Id.

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IND. INT'L & COMP. L. REV.

cam.'" Note that none of the six devices embodies an elastic rubber rod
which could prevent the scope of the Improver patent from encompassing
rubber rods as an alternative to helical springs. 6s Assuming these six patents
comprise the prior art, it is unlikely that broadening the scope of the Improver
patent to encompass elastic rubber rods will intrude upon the prior art.

In conclusion, if the Epilady dispute had been litigated in the United
States under approximately the same set of facts presented to the English and
German courts, a federal district court in the United States, applying the United
States version of the doctrine of equivalents, would probably find that the
Remington depilatory device infringed upon the Improver patent.

V. THE PATENT HARMONIZATION TREATY

A. General Overview

The aim of the Patent Harmonization Treaty (draft treaty), if it ever
becomes a reality, is the worldwide harmonization of patent laws. 66

164. Id
165. The limitation posed by the prior art is simply that the asserted range of equivalents

may not encompass the prior art at the very point at which the claims distinguish from the
art. Stewart-Warner Corp. v. City of Pontiac, 767 F.2d 1563, 1572 (Fed. Cir. 1985) (citing
Thomas & Betts Corp. v. Litton Sys., 720 F.2d 1572, 1580 (Fed. Cir. 1983) and Hughes Aircraft
Co. v. United States, 717 F.2d 1351, 1362 (Fed. Cir. 1983)). It is well established that limitations
in a claim cannot be given a range of equivalents so wide as to cause the claim to encompass
anything in the prior art. Senmed, Inc. v. Richard-Allen Med. Indus., 888 F.2d 815,821 (Fed.
Cir. 1989) (citing Perkin-Elmer Corp. v. Computervision Corp., 732 F.2d 888, 900 (Fed. Cir.
1984)). Claims may not be enlarged by equivalents to encompass the teachings of the prior
art. Tandon Corp. v. United States ITC, 831 F.2d 1017, 1026 (Fed. Cir. 1987) (citing Perkin-
Elmer Corp., 732 F.2d at 900).

166. While attention has been focused on the Uruguay Round of the General Agreement
on Tariffs and Trade (GAIT) and its intellectual property provisions known as The Agreement
on Trade-Related Aspects of Intellectual Property Rights (TRIPs), the WIPO negotiations have
been, to a large extent, on hold. Jacques J. Gorlin, Update on InternationalNegotiations on
IntellectualPropertyRights, in GLOBAL DIMENsIONS OF INTELLECTUAL PROPERTY RIGHTS
OF SCIENCE AND TECHNOLOGY 175, 176 (National Academy Press, 1992).

The GATT" negotiations on TRIPs and discussions of the WIPO share similar
objectives: the strengthened protection and improved enforcement of intellectual
property rights via multilateral instruments. However, the overwhelming interest
of the principal developed countries in a trade-based multilateral regime for
intellectual property as part of the current GATT Uruguay Round... [has] pushed
the TRIPS negotiationsto the fore.

Id. at 175.
In contrast to the Patent Harmonization Treaty though, the GATT TRIPs agreement contains

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DOCTRINE OF EQUIVALENTS

Worldwide harmonization of patent laws is of particular importance to all
applicants, especially to those who file outside their national borders.
Negotiations concerning the draft treaty have taken place before the WIPO
since 1983167 and are currently in draft form.' 68

Wide in scope, the draft treaty addresses, at least in broad terms, virtually
the entire field of patent law. Twenty-four of the draft treaty's thirty-nine
articles address substantive aspects of patent law. Included in these twenty-four
substantive articles are detailed provisions relating to issues such as statutory
subject matter,'69 novelty, 7 ' obviousness,' and the rights conferred
by patenting.'72 The draft treaty also addresses the proper legal definition
of the doctrine of equivalents and the role of the specification in construing
claim scope. 73

only minimum standards of patent protection and enforcement. Id. at 179. The WIPO negotiators
delayed their patent harmonization discussions until the GATT resolved the rules for minimum
standards of patent protection and enforcement. Id at 180. There is optimism in some circles
that ratification of the GATT TRIPs agreement will be followed by the WIPO concluding
the Patent Harmonization Treaty. Id.

167. R. Carl Moy, The History of the Patent Harmonization Treaty: Economic Self-
Interest as an Influence, 26 J. MARSHALL L. REv. 457, 459 (1993). The draft treaty has
been negotiated in a series of sessions before the WIPO of the Committee of Experts on the
Harmonization of Certain Provisions of Law for the Protection of Inventions. To date, eleven
preparatory sessions have been held.

168. Draft Treaty Supplementing the Paris Convention for the Protection of Industrial
Property As Far As Patents Are Concerned, WIPO Doc. No. PLT/DC/3 (Dec. 21, 1990) reprinted
in Records of the Diplomatic Conference for the Conclusion of a Treaty Supplementing the
Paris Convention as Far as Patents are Concerned, 30 INDUS. PROP. 118 (1991) [hereinafter
PHT].

169. Id. art. 10.
170. Id. arts. 11(2), 12-13.
171. Id. art. 1(3).
172. Id. art 19-20.
173. Id. art. 21. The relevant portions of Article 21 state:

(1) [Determination of the Extent of Protection] (a) The extent of protection
conferred by the patent shall be determined by the claims, which are to be
interpreted in the light of the description and drawings.

(b) For the purposes of subparagraph (a), the claims shall be so interpreted
as to combine fair protection for the owner of the patent with a reasonable degree
of certainty for third parties. In particular, the claims shall not be interpreted
as being confined to their strict literal wording. Neither shall the claims be
considered as mere guidelines allowing that the protection conferred by the patent
extends to what, from a consideration of the description and drawings by a person
skilled in the art, the owner has contemplated, but has not claimed.

(2) [Equivalents] (a) Notwithstanding paragraph (l)(b), a claim shall be
considered to cover not only all the elements as expressed in the claim but also

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IND. INT'L & COP. L. REV.

B. Article 21 of the Draft Treaty: The Definition of Equivalency

Article 21 of the draft treaty states that "[t]he extent of protection conferred
by the patent shall be determined by the claims, which are to be interpreted
in the light of the description and drawings.' 74 In order to avoid a restrictive
interpretation of the claim language, Paragraph (1)(b) of Article 21 asserts
that the claims shall not be limited to the literal meaning of the wording, yet
neither should they be considered as mere guidelines that would allow an
extension to what the inventor may have contemplated but has not expressly
claimed.' The doctrine of equivalents is empowered by Paragraph (2)(a)
which describes the general rule that patent protection not only extends to
elements literally expressed in the claim, but also to equivalent elements as
well. 176

Paragraph (2)(b) defines equivalent elements."7 Interestingly, the draft
treaty contains two definitions of equivalency. 7  The multiple definitions are
due to the fact that the members of the Committee of Experts could not agree
on one particular definition of equivalency, and in order to keep the doctrine
of equivalents in the draft treaty, it was necessary to place both definitions adjacent
to each other and leave it to the future Contracting States to apply one or the

equivalents.
(b) An element ("the equivalent element") shall generally be considered as

being equivalent to an element as expressed in a claim if, at the time of any alleged
infringement, either of the following conditions is fulfilled in regard to the invention
as claimed:

(i) the equivalent element performs substantially the same function in
substantially the same way and produces substantially the same result as the element
as expressed in the claim, or

(ii) it is obvious to a person skilled in the art that the same result as that
achieved by means of the element as expressed in the claim can be achieved
by means of the equivalent element.

(c) Any Contracting Party shall be free to determine whether an element is
equivalent to an element as expressed in a claim by reference to only the condition
referred to in subparagraph (b)(i) or to only the condition referred to in
subparagraph (b)(ii), provided that, at the time of depositing its instrument of
ratification of or accession to this Treaty, it so notifies the Director General.

Id.
174. Id. art. 21(l)(a).
175. Id. art. 21(l)(b).
176. Id. art. 21(2)(a).
177. Id. art. 21(2)(b).
178. Id. art. 21(2)(b)(i)-(ii).

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DOCTRINE OF EQUIVALENTS

other. " 9 The first definition coincides with the United States standard.' 80

According to the first definition, an element is an equivalent if it "performs
substantially the same function in substantially the same way and produces
substantially the same result as the element as expressed in the claim."'' The
second definition resembles the German standard and defines an equivalent element
as one in which "it is obvious to a person skilled in the art that the same result
as that achieved by means of the element as expressed in the claim can be achieved
by means of the equivalent element."' 82 In essence, the first definition requires
three conditions to be met: function, way, and result; the second requires only
one, the same result. However, the second definition also requires that the "way"
be obvious to a person skilled in the art.

C. The Treaty's Hypothetical Impact On The Epilady Controversy

If the draft treaty had been in effect in its current text when the Epilady
dispute was litigated, it would have eliminated the inconsistent decisions of the
English and German courts. The German court, finding infringement, followed
the second definition of the draft treaty. The German court, in accordance with
the requirements of the second definition, first concluded the rubber rod was
"identical in effect to a device making use of the wording of claim I of the
[Improver] patent. ...""' This satisfies the "same result" criteria of the second
definition. The German court concluded its finding of infringement by equivalency
by deciding that it would be obvious to a person skilled in the art that the same
result achieved by the helical spring could be achieved by the rubber rod."s

The English Patents Court, on the other hand, did not explicitly follow the
draft treaty, but added an exception to the determination of infringement by
equivalency not found within the four comers of the draft treaty. The English
Patents Court, like the German District Court, held that the rubber rod was an
equivalent in accordance with the second definition, but Justice Hoffmann asked
one additional question that is more or less an exception to the doctrine of
equivalents.' Justice Hoffmann's exception, his third question, said that if a reader
skilled in the art understood from the language of the claim that the patentee intended

179. Id. art. 21(2)(c). According to Article 21(2)(c) of the draft treaty, the Contracting
Parties will adopt one of the two definitions during ratification of or accession to the treaty.

180. See supra part II.B.
181. PHT, supra note 168, art. 21(2)(b)(i).
182. Id. art. 21 (2)(b)(ii).
183. Improver Corp. & Sicommerce AG v. Remington Products Inc., 24 INT'L. REV. OF

INDUS. PROP. & COPYRIGHT LAW 838, 841.

184. Id. at 843.
185. Improver Corp. & Others v. Remington Consumer Products Ltd. & Others, [1990]

F.S.R. 181, 190-1 (Eng. Ch. 1989).

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IND. INT'L & COMP. L. REV.

to confine his claim to the literal meaning of a word or phrase (in this case "helical
spring"), there could be no finding of infringement by equivalency."86 Justice
Hoffmann held that a person skilled in the art would interpret the patentee as
confining his claim to the literal meaning of helical spring, and as a result, ruled
the Remington device did not infringe on the Improver patent." 7 Had the draft
treaty been in effect and Justice Hoffmann followed it in its current text, he would
not have asked the third question, and as a result, just as the German court did,
he would have held that the Remington depilatory device infringed upon the
Improver European patent.

VI. CONCLUSION

Patent attorneys dealing with patent litigation know from experience that
a patent system without equivalents is worthless for inventors and industry. Because
of the important role the doctrine of equivalents plays in patent protection, patent
attorneys around the world would like the WIPO to develop a uniform equivalency
doctrine that can be consistently applied in the forums around the world. With
economic success dependent on the ability to compete in the global marketplace,
an industry must be able to rely upon patent protection in the foreign countries
where they conduct business.

The Epilady dispute clearly did not provide a clear set of guidelines for
future patent infringement cases in the E.C. What the Epilady dispute has done
is show that patent protection based on equivalency is by no means applied on
a consistent basis in the E.C. national courts despite having a uniform standard.
For the time being, advocates for the holders of European Patents must accept
the reality of diversity. Codification and harmonization of the doctrine of equivalents
in the Patent Harmonization Treaty would facilitate the preparation and prosecution
of patent infringement suits. For this reason, the WIPO's initiative on protection,
scope, and claim interpretation deserves full support. Worldwide recognition of
the doctrine of equivalents, and consistent application thereof, would be a
monumental step toward increased enforceability of patents on an international
scale.

John P. Hatter Jr.*

186. Id. at 187.
187. Id. at 193.

* J.D. Candidate, 1996, Indiana University School of Law-Indianapolis; B.S.M.E.,
1986 Purdue University; M.B.A., 1989, Winthrop University. The author thanks Mr. Charles
Reeves for bringing the Epilady controversy to his attention. The author especially thanks
his wife, Trudi, and their two daughters, Bridget and Breanna, for their understanding and
support throughout this project.

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