UNITED STATES COURT OF APPEALS FOR THE FEDERAL CIRCUIT
95-1448
TANABE SEIYAKU CO., LTD.
and MARION MERRELL DOW, INC.,
v.
UNITED STATES
INTERNATIONAL TRADE COMMISSION,
and
ORION CORPORATION FERMION, COPELY PHARMACEUTICALS, INC.
INTERCHEM CORPORATION and RHONE-POULENC RORER, INC.,
S. Leslie Misrock, Pennie & Edmonds, of New York New York,
argued for appellants. With him on the brief were Marcia H. Sundeen,
of Washington, D.C., and Joseph Diamante, of New York.
Cynthia P. Johnson, Attorney, Office of General Counsel, U.S.
International Trade Commission, of Washington, D.C., argued for appellee.
With her on the brief were
Lyn M. Schlitt, General Counsel, and James A. Toupin,
Deputy General Counsel.
Richard D. Kelly, Oblon, Spivak, McClelland, Maier & Neustadt,
P.C., of Arlington, Virginia, argued for intervenors. With him on the brief
were Stephen G. Baxter and Martin M. Zoltick.
Appealed from: United States International Trade Commission
United States Court of Appeals for the Federal
Circuit
95-1448
TANABE SEIYAKU CO., LTD. and
MARION MERRELL DOW, INC.,
v.
UNITED STATES INTERNATIONAL TRADE COMMISSION,
--and--
ORION CORPORATION FERMION,
COPLEY PHARMACEUTICALS,INC.,
INTERCHEM CORPORATION and
RHONE-POULENC RORER, INC.,
______________________
DECIDED: March 7, 1997
______________________
Before PLAGER, SCHALL, and BRYSON, Circuit Judges.
PLAGER, Circuit Judge.
Tanabe Seiyaku Co., Ltd. and Marion Merrell Dow, Inc. (collectively
"Tanabe") appeal from a final determination of the United States
International Trade Commission ("Commission"), in In re Certain
Diltiazem Hydrochloride & Diltiazem Preparations, No. 337-TA-349.
Tanabe petitioned the Commission for a determination that the importation
and sale of diltiazem by certain named respondents was a violation of United
States law because the product was produced by a process that infringed
a patent owned by Tanabe. The Commission denied the petition. Tanabe appealed
to this court. We affirm the Commission's decision.
BACKGROUND
1.
Section 1337 prohibits "[t]he importation into the United States
. . . of articles that . . . are made, produced, processed, or mined under,
or by means of, a process covered by the claims of a valid and enforceable
United States patent." 19 U.S.C. 1337(a) (1994)(1).
Tanabe in its complaint to the Commission alleged that respondents by the
importation, sale for importation, and sale within the United States of
diltiazem hydrochloride and diltiazem preparations, produced by a process
infringing claim 1 of United States Patent No. 4,438,035 (the "'035
patent"), were in violation of 1337. The complaint sought an investigation
by the Commission and, based on the investigation, issuance of a permanent
exclusion order and permanent cease and desist orders. The complaint named
ten respondents; this appeal concerns the Commission's determination as
it applies to four of the respondents, Orion Corporation Fermion, Interchem
Corporation, Copley Pharmaceuticals, Inc., and Rhone-Poulenc Rorer, Inc.
(collectively "Fermion").
The Commission referred the matter to an administrative law judge ("ALJ")
for an evidentiary hearing and initial determination. The proceedings were
suspended during reexamination proceedings of the patent, requested by
certain of the respondents. The suspension was lifted after the United
States Patent and Trademark Office ("PTO") confirmed the patentability
of all claims of the '035 patent, including claim 1, the only claim at
issue.
The ALJ, following extensive pre-trial proceedings and a two-week hearing
involving all parties, in an exhaustive 334-page opinion concluded that
claim 1 was not infringed by any of the respondents, was invalid because
it was obvious in view of the prior art, and was unenforceable due to inequitable
conduct in its procurement.(2) On certification
to the Commission, the Commission affirmed the ALJ's disposition of the
matter, albeit on narrower grounds than those recited by the ALJ.
The Commission limited its affirmance to the ALJ's interpretation of
claim 1 and his consequent conclusion that the '035 patent was not infringed
by any of the respondents. The Commission did not find it necessary to
reach the issues of validity and enforceability, and took no position on
those issues. Further, the Commission, by not reviewing them, caused the
ALJ's findings in his initial determination regarding importation and the
existence of a domestic industry to become a part of the Commission's final
determination.
The '035 patent is a method or process patent. It discloses and claims
a chemical process for preparing diltiazem hydrochloride, a pharmaceutical
product used to treat various cardiovascular diseases, sold in dosage form
by Tanabe under the name CARDIZEM®. There was an earlier, now expired,
patent on the product itself, diltiazem hydrochloride, United States Patent
No. 3,562,257 (the "'257 patent"), also assigned to Tanabe. This
product patent and its prosecution play a significant part in the Commission's
interpretation of claim 1 of the '035 patent, as shall be explained below.
That claim, claim 1 of the '035 patent, reads:
A method of preparing a benzothiazepine derivative of the formula:
[Insert structure for compound I]
wherein R is a hydrogen or acetyl, or a pharmaceutically acceptable acid
addition salt thereof, which comprises condensing a compound of the formula:
[Insert structure for compound II]
wherein R is the same as defined above, with 2-(dimethylamino)ethyl halide
either in the presence of potassium hydroxide in acetone or in the presence
of potassium carbonate in a solvent selected from acetone, lower alkyl
acetate, a mixture of acetone and water and a mixture of lower alkyl acetate
and water, and if required, further converting the product into a pharmaceutically
acceptable acid addition salt thereof.
(emphasis added).
The chemical reaction recited in claim 1 is known as an "N-alkylation"
reaction. Compound II, the starting material for the N-alkylation reaction,
is sometimes referred to as "TZP." At issue on appeal is the
emphasized portion of the claim, which recites five combinations of "bases"
and "solvents" used in performing the chemical reaction. The
five base-solvent combinations disclosed in the '035 patent and recited
in claim 1 are:
| Combination |
Base |
Solvent |
| 1 |
potassium hydroxide |
acetone |
| 2 |
potassium carbonate |
acetone |
| 3 |
potassium carbonate |
acetone and water |
| 4 |
potassium carbonate |
lower alkyl acetate |
| 5 |
potassium carbonate |
lower alkyl acetate and water |
The accused Fermion process involves performing the N-alkylation of
TZP in the presence of the base potassium carbonate and, rather than acetone,
the solvent butanone (also known as "methyl ethyl ketone" or
"MEK") mixed with water. Because the parties agree that the use
of this base-solvent combination is not within the literal language of
claim 1, the issue before the Commission, and now before us, is whether
claim 1 is infringed under the doctrine of equivalents. More specifically,
the issue is whether the use of butanone in the Fermion process instead
of the acetone in the patent claim constitutes a "substantial"
or "insubstantial" difference between the accused process and
the patent. If the difference is substantial, there would be no infringement
under the doctrine as it has recently been enunciated by this court, see
Hilton Davis Chem. Co. v. Warner-Jenkinson Co., 62 F.3d 1512, 35
USPQ2d 1641, (Fed. Cir. 1995) (in banc), rev'd on other grounds,
No. 95-728, 1997 WL 84999 (U.S. Mar. 3, 1997); if the difference is insubstantial,
there would be infringement, and therefore the importation and sale of
the product produced by the process would be in violation of 1337.
2.
Solvents are used to dissolve reactants, which permits the reactants
to come into contact with each other and undergo chemical reactions. Butanone
and acetone are similar in that they are both "ketones" (organic
compounds having a "carbonyl group"). Moreover, they are "homologs,"
that is, they differ only in that butanone contains an additional "methylene
group." Their structures are illustrated below:
[Insert structures]
Acetone Butanone
In interpreting claim 1, and in assessing infringement under the doctrine
of equivalents, the Commission(3) considered
the claim language, the patent specification, the prosecution history,
and certain extrinsic evidence. The Commission noted that Tanabe filed
a Statement of Art with the PTO dated January 6, 1983. The statement called
the examiner's attention to the '257 patent (the earlier product patent)
and one other reference. In distinguishing the claimed invention of the
'035 patent from the '257 patent, Tanabe stated:
In contrast, Applicants' invention is the condensation of the acylated
form of reference compound II (our II) without prior conversion to the
alkali metal salt thereof but rather in the presence of potassium hydroxide
in acetone or potassium carbonate in acetone, lower alkyl acetate, water-acetone,
or water-lower alkyl acetate.
The Commission noted that in this statement, as well as in claim 1,
Tanabe chose to describe its invention in the form of exact base-solvent
combinations, rather than in terms of categories of bases and solvents,
which Tanabe had done in its '257 patent, and in other patents.
The Commission also noted that Tanabe distinguished the invention claimed
in the '035 patent over the prior art '257 patent on the basis that the
precise base-solvent combinations claimed by Tanabe provide high yields
under safe and economical conditions. Tanabe represented to the PTO: "[I]t
is clear that the reference process yields are in the range of 65 to 70%
. . . . Applicants' invention, on the other hand, gives yields which are
no less than 87%. It is therefore clear that applicants' invention is patentable
over the prior art."
The Commission noted that the '035 patent does not mention the use of
any organic solvent other than acetone and lower alkyl acetates. The Commission
found it "particularly noteworthy that although the '035 patent discloses
a subclass of 'lower alkyl acetates,' it did not disclose a class or subclass
of lower alkyl ketones. Rather, the disclosure of ketones was limited to
a single ketone, i.e., acetone."
The Commission contrasted the language of claim 1 and the disclosure
of only two solvents with Tanabe's disclosure of a range of solvents in
the '257 patent. In that patent, Tanabe disclosed that the N-alkylation
reaction is carried out in "a solvent (e.g. dioxane, toluene, xylene,
dimethylsulfoxide)." The Commission concluded that one of ordinary
skill in the art reading the '035 patent and file history "would conclude
that the only solvents taught by the '035 patent as suitable for the claimed
N-alkylation reaction were acetone and lower alkyl acetates, which in some
cases may be mixed with water."
The Commission also considered statements made by Tanabe to foreign
patent offices in prosecuting '035 counterpart applications in Finland
and Israel, and before the European Patent Office ("EPO"). The
'035 counterpart applications were initially rejected by all three of those
patent offices, all citing United States Patent No. 3,075,967 to Krapcho
("'967 patent"). In response to those rejections, Tanabe argued
that the invention was patentable over the '967 patent because Tanabe's
five specific base-solvent combinations gave unexpectedly better results
than other combinations of bases and solvents. Tanabe submitted a Comparative
Test Report to show the examiners that the five specific base-solvent combinations
were better than other base-solvent combinations. Tanabe argued to each
of the three patent offices that its invention was not obvious, stating:
Judging from the facts (i) that [the '967 patent] teaches neither the
use of potassium carbonate as the base nor the use of specific base-solvent
combinations to be employed in the method of the present invention; (ii)
that, when the condensation reaction was carried out by the use of sodium
hydroxide or sodium carbonate as the base, the yield of the product was
less than 10%; and (iii) that, even if potassium hydroxide or potassium
carbonate was used as the base, the yield of the product was less than
30% in the case where dioxane, toluene or methanol was used, it is believed
that the above mentioned advantages of the present invention have never
been taught or suggested by [the '967 patent]. Thus [use of] the specific
base-solvent combinations of the present invention is not obvious.
(emphasis added).
The Commission concluded that, based on claim language and the statements
made to foreign patent offices as part of the prosecution history, Tanabe
showed that it "intended to exclude all bases and solvents other than
as particularly claimed, including those that might generally be thought
of as equivalent, because the inventors believed that only through the
unique base/solvent combinations stated could their requirements to produce
diltiazem in high yield be realized."
In evaluating whether Fermion's process infringes under the doctrine
of equivalents, the Commission noted that the burden was on Tanabe to show
that the substitution of butanone for acetone was an insubstantial change.
The Commission observed that acetone is chemically related to butanone
and that a person skilled in the art might normally be expected to try
to substitute butanone for acetone. However, it determined that a person
skilled in the art would notice the specificity and exclusivity of claim
1 regarding the use of acetone in the N-alkylation reaction, and would
conclude that other ketones, such as butanone, were not included because
they did not work. It also noted that simply substituting butanone for
acetone in the '035 patent examples would not generally work, unless conditions
were carefully controlled, and that the '035 patent does not teach how
to optimize critical process variables. The Commission concluded that:
In view of Tanabe's decision to use restrictive language in the claims
of the '035 patent, specifying only acetone and no other keytone [sic,
ketone] solvent, and given the admissions made to the PTO about the specificity
of the claimed invention, and the further admissions Tanabe made to the
EPO and other foreign patent offices, it has not been shown that Fermion's
use of MEK is equivalent to the acetone covered by claim 1 of the '035
patent. Therefore, it has not been demonstrated that the accused Fermion
process infringes claim 1 of the '035 patent.
DISCUSSION
On appeal, Tanabe asserts that the Commission erred in its construction
of claim 1 and in its consequent determination that Fermion's process did
not infringe under the doctrine of equivalents. Tanabe further asserts
that the Commission erroneously invoked an estoppel against Tanabe regarding
the proper range of equivalents based upon the purported subjective intent
of the inventors, limitations not a part of claim 1, and irrelevant statements
made to foreign patent offices.
The determination of whether an accused product or process infringes
a claim in a patent is universally understood to involve two steps. First,
we construe the claim asserted to be infringed to determine its meaning
and scope. Second, we compare the properly construed claim to the accused
product or process. Markman v. Westview Instruments, Inc., 52 F.3d
967, 976, 34 USPQ2d 1321, 1326 (Fed. Cir. 1995) (in banc), aff'd,
116 S. Ct. 1384 (1996). In addressing these two steps, the burden is on
the patent owner to establish infringement by a preponderance of the evidence.
SmithKline Diagnostics Inc. v. Helena Lab. Corp., 859 F.2d 878,
889, 8 USPQ2d 1468, 1477 (Fed. Cir. 1988). The patent owner must show that
every limitation of the patent claim asserted is found in the accused process
or product, either literally or under the doctrine of equivalents. Id.
Whether a product or process infringes the properly construed claims
of a patent, literally or under the doctrine of equivalents, is a question
of fact. Hilton Davis Chem. Co. v. Warner-Jenkinson Co., 62 F.3d
1512, 1520, 35 USPQ2d 1641, 1647 (Fed. Cir. 1995) (in banc), rev'd on
other grounds, No. 95-728, 1997 WL 84999 (U.S. Mar. 3, 1997). We review
factual determinations of the Commission under the "substantial evidence"
standard. 19 U.S.C. 1337(c) (1994); 5 U.S.C. 706 (1994). The proper construction
of a claim, on the other hand, is solely a matter of law, over which on
appeal we exercise complete and independent review. Markman, 52
F.3d at 979, 34 USPQ2d at 1329.
To determine the meaning and scope of a claim, we examine the claim
language, the specification, and the prosecution history. Extrinsic evidence,
that is, evidence outside the record before the PTO, such as expert testimony
about how those skilled in the art would interpret certain language in
the claim, may also be considered when appropriate as an inherent part
of the process of claim construction and as an aid in arriving at the proper
construction of the claim. Id.
To determine whether solvents other than those recited in claim 1 could
be used in the claimed N-alkylation reaction without fear of infringement,
a competitor would look to the claim language, the specification, and the
patent's prosecution history. The Commission correctly noted that, in the
specification and claims, Tanabe chose to define its invention in terms
of specific base-solvent combinations, rather than in terms of categories
of bases and solvents. A person skilled in the art would know that Tanabe
could have used the term "lower alkyl ketone" to describe a class
of ketone solvents including butanone and acetone. Tanabe used a similar
term to describe a class of acetate solvents, claiming the use of a "lower
alkyl acetate" solvent, either by itself or with water, rather than
claiming only a specific acetate solvent.
For ketone solvents, Tanabe took a different approach to describing
and claiming its invention, describing and claiming acetone as the only
ketone solvent, to be used either by itself or with water. This specific
claim language would suggest to a person skilled in the art that ketones
other than acetone may not be useful for the N-alkylation reaction. In
other words, the claim language itself, and the specification, suggest
that substituting butanone for acetone is not an insubstantial change.
Although we do not speculate on Tanabe's reasons for disclosing and claiming
the use of only one ketone solvent, we note that:
the doctrine of equivalents is not available for the attainment in court
of a scope of protection which encompasses subject matter deliberately
removed from examination by the PTO during prosecution through narrow claiming.
. . . [I]t is impermissible to erase under the doctrine of equivalents
"meaningful limitations of the claim on which the public is entitled
to rely in avoiding infringement."
Genentech, Inc. v. Wellcome Found., Ltd., 29 F.3d 1555, 1568
n.41, 31 USPQ2d 1161, 1171 n.41 (Fed. Cir. 1994) (citation omitted).
In considering the prosecution history of the '035 patent, the Commission
correctly noted that in a Statement of the Art filed by Tanabe with the
PTO, Tanabe defined its invention in terms of the exact base-solvent combinations
recited in claim 1. Tanabe also stated that its process resulted in "yields
which are no less than 87%." Consequently, a review of the prosecution
history by a competitor would reinforce the suggestion in the claim language
and specification that using other ketone solvents, such as butanone, is
not an insubstantial change from using acetone. Moreover, the prosecution
history suggests that other ketone solvents may result in lower yields
than the claimed solvents.
The sharply restricted nature of the claims has much to do with the
scope we accord to the doctrine of equivalents. Tanabe contends that the
Commission erred in limiting the scope of equivalents based upon the inventors'
purported intent and in relying on the inventors' pre-application experiments.
In support, Tanabe cites the following statement in a footnote in the initial
decision:
Tanabe's decision not to disclose the use of other ketones might have
been based on experimental failures, such as Tanabe's failed TZP N-alkylation
experiment with potassium hydroxide as the base and toluene as the solvent.
Testimony at the hearing by the inventors might have elucidated this subject
further.
Tanabe also refers the court to other statements in the initial decision,
including: "Tanabe's [1981] experiments with MEK either resulted in
no product or impure product," and a statement in a footnote that
"[t]his failure on Tanabe's part may explain why MEK was not claimed
in the '035 patent." Tanabe then cites Atlas Powder Co. v. E.I.
du Pont De Nemours & Co., 750 F.2d 1569, 224 USPQ 409 (Fed. Cir.
1984), and argues that the Commission erred in relying on the inventors'
pre-application experiments to determine that butanone is not interchangeable
with acetone. Tanabe asserts that the Commission improperly relied on Tanabe's
confidential laboratory notebooks in concluding that experiments not part
of the prosecution history create an "experimental estoppel"
that limits the application of the doctrine of equivalents in this case.
We do not read the Commission's opinion to establish any estoppel based
on pre-application experiments performed by Tanabe. On the contrary, the
Commission properly considered Tanabe's pre-application experiments in
assessing whether there is a substantial difference between the claimed
and accused processes. Tanabe's unsuccessful experiments with butanone
indicate that the inventors did not consider butanone to be interchangeable
with acetone for use in the claimed N-alkylation process.
The Commission also considered the statements made by Tanabe in prosecuting
foreign counterparts to the '035 patent. As earlier explained, in response
to rejections for obviousness Tanabe argued that its process was patentable
over the prior art because its five specific base-solvent combinations
gave unexpectedly better results than other combinations of bases and solvents.
Tanabe submitted a Comparative Test Report to demonstrate the effectiveness
of its base-solvent combinations. Tanabe argued before the EPO, and the
Finland and Israel patent offices, that use of "the specific base-solvent
combinations of the present invention is not obvious."
Tanabe argues that the Commission erred in considering foreign prosecution
history, improperly finding a "foreign prosecution estoppel"
to limit the application of the doctrine of equivalents. We do not read
the Commission's decision to establish any estoppel related to the prosecution
of foreign counterparts to the '035 patents. In evaluating infringement
under the doctrine of equivalents, "representation[s] to foreign patent
offices should be considered . . . when [they] comprise relevant evidence."
Caterpillar Tractor Co. v. Berco, S.p.A., 714 F.2d 1110, 1116, 219
USPQ 185, 188 (Fed. Cir. 1983).
In the present case, the representations made to foreign patent offices
are relevant to determine whether a person skilled in the art would consider
butanone or other ketones to be interchangeable with acetone in Tanabe's
claimed N-alkylation reaction. Because Tanabe represented that its "specific
base-solvent combinations" distinguish its process from the prior
art, Tanabe's statements to foreign patent offices suggest to a person
skilled in the art that other solvents, including butanone, may not be
interchangeable with the claimed solvents.
In determining that butanone is not interchangeable with acetone in
the claimed N-alkylation reaction, the Commission reviewed experiments
performed by Fermion and by Tanabe's expert, Professor Baldwin. The Commission
found that Professor Baldwin's tests demonstrate that substituting butanone
for the claimed solvents resulted in lower yields or productivity than
that achieved in the examples in the patent. As for Fermion's tests, the
Commission found that Fermion duplicated examples disclosed in the patent,
substituting butanone for the disclosed solvents, and found that butanone
generally produced substantially worse results.
There was an exception. The Commission found that when Fermion substituted
butanone for acetone in Example 2, the reaction produced a slightly better
yield with butanone. Tanabe argues that these results are "dispositive,"
and indicate that Fermion's process infringes under the doctrine of equivalents.
Example 2 teaches conditions for performing the N-alkylation reaction using
potassium carbonate as the base and acetone and water as the solvent system.
Although when Fermion substituted butanone for acetone in this example,
it achieved similar results to those reported in the patent for Example
2, the Commission also found that Fermion was unable to duplicate Example
2 using butanone in larger-scale pilot plant tests on two occasions.
To determine how to adjust reaction conditions to achieve consistent
results in its N-alkylation process, Fermion conducted numerous experiments
between 1983 and 1986. By performing these experiments, Fermion learned
to adjust critical process conditions to achieve consistent high yields
for the N-alkylation reaction. The extensive experimentation performed
by Fermion, which involved a variety of solvents, bases, and reaction conditions,
suggests that Fermion's activities are better described as "designing
around" the '035 patent rather than "copying." Moreover,
these experiments support the conclusion that butanone is not readily interchangeable
with acetone in the claimed process.
Although the preceding review of the claim and its proper construction
is more than sufficient to affirm the Commission's conclusion, the record
shows that the parties also presented evidence on whether Fermion's process
satisfies the function-way-result test for infringement under the doctrine
of equivalents. See Hilton Davis, 62 F.3d at 1517-18, 35
USPQ2d at 1645. The Commission found that the claimed process operates
by way of a "surface solvent phase," and that Tanabe offered
no evidence that a surface solvent phase was present in the Fermion process.
The Commission's decision that Fermion's process does not infringe the
'035 patent under the doctrine of equivalents reflects a proper construction
of the patent claim, and to the extent it is dependent on factual determinations,
is supported by substantial evidence. We have considered Tanabe's other
arguments on appeal and find them to be unpersuasive.
CONCLUSION
Accordingly, the Commission's decision is
AFFIRMED.
Each party to bear its own costs.
1. 1 This court has exclusive jurisdiction "to
review the final determinations of the United States International Trade
Commission relating to unfair practices in import trade, made under section
337 of the Tariff Act of 1930 (19 U.S.C. 1337)." 28 U.S.C. 1295(a)(6)
(1994).
2. 2 The ALJ also issued Order No. 52, granting a
motion for sanctions against Tanabe due to the failure of five Tanabe witnesses
to answer deposition questions. The sanctions were issued as alternative
relief, to be imposed only in the event that the Commission concluded that
respondents infringed the '035 patent. The Commission's disposition of
the matter mooted the order.
3. 3 The opinion of the Commission itself is a relatively
brief nine pages, and essentially approves the findings and conclusions
of the ALJ as recited in his much more extensive opinion. References therefore
to "the Commission's" findings and conclusions incorporate the
findings of the ALJ as well as the conclusions of both the ALJ in his initial
decision and the Commission in its final decision.