Patent No. 835120, issued November 6, 1906, to Henry Livingstone
Sulman
et al. for improvements in the concentration of
ores by a process of oil flotation is valid as to Claims Nos. 1, 2,
3, 5, 6, 7 and 12, but invalid as to Claims Nos. 9, 10 and 11. The
process covered by the patent, as sustained, is simpler and more
economical, and has proved more successful than the flotation
processes relied on as anticipations; it accomplishes separation of
metallic particles from ore pulp not through the buoyancy of oil
alone, but largely also through the buoyancy of air bubbles
introduced into the mixture of ore, water, and oil by means of an
agitation differing in kind and degree from that previously
employed, and it results
Page 242 U. S. 262
in a froth concentrate of peculiar constitution and stability.
For these reasons, it is held to be a patentable invention.
It is persuasive evidence of invention that the process in suit
came immediately into general use, and has largely replaced all
earlier like processes without the aid of puffing or business
exploitation.
The patentees planned the experiments, directed the
investigations day by day, conducted them largely in person, and
interpreted the results, and they cannot be denied the status of
original discoverer on the ground that their employee made the
analyses and observations which resulted immediately in the
discovery.
Agawam Company v.
Jordan, 7 Wall. 583-603.
A patent for a process of ore concentration which, because of
the varied character of the subject matter, necessarily requires
preliminary tests by the user to apply it most successfully to the
ores treated is not on that account invalid if the process is
described in the claims with sufficient definiteness to guide those
skilled in the art to a successful use of it.
The particularity and certainty of disclosure which the law
requires in patents is not greater than is reasonable, having
regard to their subject matter.
Any variation from the process disclosed in a patent must come
within the claims of the patent to constitute an infringement.
214 F. 100 reversed.
The case is stated in the opinion. For the opinion of the
district court,
see 207 F. 956.
MR. JUSTICE CLARKE delivered the opinion of the Court.
In this suit, the complainants, the first named as the owner and
the other as general licensee, claim an infringement
Page 242 U. S. 263
of United States letters patent No. 835,120, issued on the 6th
day of November, 1906, to Henry Livingston Sulman, Hugh Fitzalis
Kirkpatrick-Picard, and John Ballot. The usual injunction,
accounting, and damages are prayed for. The district court
sustained the patent as to claims numbered 1, 2, 3, 5, 6, 7, 9, 10,
11, and 12; found that the defendant had infringed each of these
claims, and granted the prayer of the petition. The Circuit Court
of Appeals for the Ninth Circuit reversed the decree of the
district court and remanded the case with instructions to dismiss
the bill. The case is here on writ of certiorari to review that
decision.
As stated in the specification, the claimed discovery of the
patent in the suit relates
"to improvements in the process for the concentration of ores,
the object being to separate metalliferous matter from gangue by
means of oils, fatty acids, or other substances which have a
preferential affinity for such metalliferous matter over
gangue."
The answer denies all of the allegations of the bill and avers
that, in twenty-five designated United States and five British
patents, the process described in suit was "fully and clearly
described and claimed," and it also avers that the claimed
discovery was invented, known, and used by many persons long prior
to the time when the application was made for the patent in suit.
Notwithstanding this elaboration of denial, counsel for the
defendant, in the summarized conclusion to their brief, rely upon
only five of the many patents referred to as showing that the
patent in suit was anticipated and is therefore invalid for want of
novelty and invention,
viz.: Everson (1886), Froment
(Italy, 1902; Great Britain, 1903), Glogner (1903), Schwarz
(applied for April 19, 1905, issued December 19, 1905), and Kirby
(applied for October 17, 1903, issued December 18, 1906). And the
defendant, a man obviously experienced in the subject, says that,
in his opinion, the
Page 242 U. S. 264
whole basis of flotation concentration was disclosed in the
Everson United States patent No. 348,157 and in the Froment British
patent.
It is clear that in the prior art, as it is developed in this
record, it was well known that oil and oily substances had a
selective affinity or attraction for, and would unite mechanically
with, the minute particles of metal and metallic compounds found in
crushed or powdered ores, but would not so unite with the quartz,
or rocky nonmetallic material, called "gangue." Haynes British
patent (1860), and United States patents, Everson (1885), Robson
(1897), and Elmore (1901). It was also well known that this
selective property of oils and oily substances was increased when
applied to some ores by the addition of a small amount of acid to
the ore and water used in process of concentration. United States
patents, Everson (1885), Elmore (1901), and Cattermole (1904).
Prior to the date of the patent in suit, a number of patents had
been granted in this and other countries for processes aiming to
make practical use of this property of oil and of oil mixed with
acid in the treatment of ores, all of which, speaking broadly,
consisted in mixing finely crushed or powdered ore with water and
oil, sometimes with acid added, and then in variously treating the
mass -- "the pulp" -- thus formed so as to separate the oil, when
it became impregnated or loaded with the metal and metal-bearing
particles, from the valueless gangue. From the resulting
concentrate the metals were recovered in various ways.
The processes of this general character described in the prior
patents may be roughly divided into two classes. The process in the
patents of the first class is called in the record the "surface
flotation process," and it depends for its usefulness on the oil
used being sufficient to collect and hold in mechanical suspension
the small particles of metal and metalliferous compounds, and by
its buoyancy
Page 242 U. S. 265
to carry them to the surface of the mixture of ore, water, and
oil, thus making it possible, by methods familiar to persons
skilled in the art, to float off the concentrate thus obtained into
any desired receptacle. The waste material, or gangue, not being
affected by the oil, and being heavier than water, sinks to the
bottom of the containing vessel and may be disposed of as
desired.
The process of the other class, called in the record the "metal
sinking process," reverses the action of the surface flotation
process and is illustrated by the Cattermole U.S. patent, No.
777,273, in which oil is used to the extent of 4 percent to 6
percent to 10 percent of the weight of the metalliferous mineral
matter, depending on the character of the ore, for the purpose of
agglomerating the oil-coated concentrate into granules heavier than
water, so that they will sink to the bottom of the containing
vessel, permitting the gangue to be carried away by an upward
flowing stream of water.
The process of the patent in suit, as described and practised,
consists in the use of an amount of oil which is "critical," and
minute as compared with the amount used in prior processes,
"amounting to a fraction of one percent on the ore," and in so
impregnating with air the mass of ore and water used, by agitation
-- "by beating the air into the mass" -- as to cause to rise to the
surface of the mass, or pulp, a froth, peculiarly coherent and
persistent in character, which is composed of air bubbles with only
a trace of oil in them, which carry in mechanical suspension a very
high percentage of the metal and metalliferous particles of ore
which were contained in the mass of crushed ore subjected to
treatment. This froth can be removed and the metal recovered by
processes with which the patent is not concerned.
It is obvious that the process of the patent in suit, as we have
described it, is not of the metal sinking class, and while it may,
in terms, be described as a surface
Page 242 U. S. 266
flotation process, yet it differs so essentially from all prior
processes in its character in its simplicity of operation and in
the resulting concentrate that we are persuaded that it constitutes
a new and patentable discovery.
The prior processes which we have described required the use of
so much oil that they were too expensive to be used on lean ores,
to which they were intended to have their chief application, and
the efforts of investigators for several years prior to the
discovery of the process in suit had been directed to the search
for a means or method of reducing the amount of oil used, and it is
clear from the record that approach was being made, slowly, but
more and more nearly, to the result which was reached by the
patentees of the process in suit in March, 1905. The Froment Great
Britain patent (1903) and the Kirby United States patent (applied
for in 1903 and granted in 1906) are especially suggestive of the
advance which was being made toward the desired result, but the
Froment process was little more than a laboratory experiment, and
has never proved of value in practice, and the Kirby process,
though approaching, in some respects, more nearly to the end
attained by the process of the patent in suit, found its preferred
application in the use of an amount of oil solution equal to one
fourth to three fourths in weight of the ore treated, which was
prohibitive in cost.
Into this field of investigation at this stage of its
development came the patentees of the patent in suit. They were
experienced metallurgists of London, of inventive genius and with
financial resources, and they entered upon an investigation of the
processes of oil concentration of ores which was continued through
several years, and consisted of a very extended series of
experiments in which the quantities of oil, of water, and of acid
used and the extent and character of the agitation of the mass
under treatment resorted to were varied to an almost
unparalleled
Page 242 U. S. 267
extent as to each factor, and the results were carefully
tabulated and interpreted. It was while pursuing a comprehensive
investigation of this character, having, as the evidence shows, the
special purpose in mind at the time to trace the effect on the
results of the process of a reduction to the vanishing point of the
quantity of oil used, that the discovery embodied in the patent in
suit was made. The experimenters were working on the Cattermole
"Metal Sinking Process" as a basis when it was discovered that the
granulation on which the process depended practically ceased when
the oleic acid (oil) was reduced to about five-tenths of one
percent "on the ore." It was observed, however, that, as the amount
of oleic acid was further reduced and the granulation diminished,
there was an increase in the amount of "float froth," which
collected on the surface of the mass, and that the production of
this froth reached its maximum when about one-tenth of one percent
or slightly less "on the ore" of oleic acid was used. This froth,
on collection, was found to consist of air bubbles modified by the
presence of the minute amount of oil used, and holding in
mechanical suspension between 70 percent and 80 percent of the
total mineral content of the mass treated. It was promptly
recognized by the patentees that this froth was not due to the
liberation of gas in the mass treated by the action of the dilute
acid used, and its formation was at once attributed in large part
to the presence of the air introduced into the mixture by the
agitation which had been resorted to to mix the oil with the
particles of crushed ore, which air, in bubbles, attached itself to
the mineral particles, slightly coated as they were with what was
necessarily an infinitesimal amount of oil, and floated them to the
surface. The extent of the agitation of the mass had been increased
as the experiments proceeded until the "series of Gabbett mixers,
fitted with the usual baffles, were speeded at from 1,000 to 1,100
revolutions per minute."
Page 242 U. S. 268
A careful consideration of the record in this case convinces us
that the facts with respect to the process of the patent in suit
are not overstated by the plaintiffs' witness, Adolph Liebmann, an
expert of learning and experience, when he says in substance:
"The present invention differs essentially from all previous
results. It is true that oil is one of the substances used, but it
is used in quantities much smaller than was ever heard of, and it
produces a result never obtained before. The minerals are obtained
in a froth of a peculiar character, consisting of air bubbles
which, in their covering film, have the minerals embedded in such
manner that they form a complete surface all over the bubbles. A
remarkable fact with regard to this froth is that, although the
very light and easily destructible air bubbles are covered with a
heavy mineral, yet the froth is stable and utterly different from
any froth known before, being so permanent in character that I have
personally seen it stand for twenty-four hours without any change
having taken place. The simplicity of the operation, as compared
with the prior attempts, is startling. All that has to be done is
to add a minute quantity of oil to the pulp, to which acid may or
may not be added, agitate for from two and one half to ten minutes,
and then, after a few seconds, collect from the surface the froth,
which will contain a large percentage of the minerals present in
the ore."
It is not necessary for us to go into a detailed examination of
the process in suit to distinguish it from the processes of the
patents relied on as anticipations, convinced as we are that the
small amount of oil used makes it clear that the lifting force
which separates the metallic particles of the pulp from the other
substances of it is not to be found principally in the buoyancy of
the oil used, as was the case in prior processes, but that this
force is to be found, chiefly, in the buoyancy of the air bubbles
introduced into the mixture by an agitation greater than and
Page 242 U. S. 269
different from that which had been resorted to before, and that
this advance on the prior art and the resulting froth concentrate
so different from the product of other processes make of it a
patentable discovery as new and original as it has proved useful
and economical. It results, without more discussion, that we fully
agree with the decision of the House of Lords, arrived at upon a
different record and with different witnesses, but when dealing
with the equivalent of the patent in suit, in
Minerals
Separations v. British Ore Concentration Syndicate, 27 R.P.C.
33. In this decision Lord Shaw, speaking for the court and
distinguishing the process there in suit especially from the Elmore
oil flotation process, which had gone before, but which was typical
of the then prior art, said:
"They [the patentees of the agitation froth process of the
patent in suit] are not promoting a method of separation which had
before been described, but they are engaged upon a new method of
separation. Instead of relying upon the lesser specific gravity of
oil in bulk, they rely upon the production of a froth by means of
an agitation which not only assists the process of the minute
quantities of oil reaching the minute particles of metal, but forms
a multitude of air cells, the buoyancy of which air cells, forming
around single particles of the metal, floats them to the surface of
the liquid."
And Lord Atkinson said:
"In their process, this mysterious affinity of oil for the
metallic particles of the ore is availed of, yet the oil is used in
such relatively infinitesimal quantities that the metallic
particles are only coated with a thin film of it, and the lifting
force is found not in the natural buoyancy of the mass of added
oil, but in the buoyancy of air bubbles which, introduced into the
mixture by the more or less violent agitation of it, envelop or
become attached to, the thinly oiled metallic particles and raise
them to the surface, where they are maintained by what is styled
the surface tension of the water. "
Page 242 U. S. 270
The record shows not only that the process in suit was promptly
considered by the patentees as an original and important discovery,
but that it was immediately generally accepted as so great an
advance over any process known before that, without puffing or
other business exploitation, it promptly came into extensive use
for the concentration of ores in most, if not all, of the principal
mining countries of the world, notably in the United States,
Australia, Sweden, Chile, and Cuba, and that, because of its
economy and simplicity, it has largely replaced all earlier
processes. This, of itself, is persuasive evidence of that
invention which it is the purpose of the patent laws to reward and
protect.
Diamond Rubber Co. v. Consolidated Rubber Tire
Co., 220 U. S. 428;
Carnegie Steel Co. v. Cambria Iron Co., 185 U.
S. 403,
185 U. S.
429-430;
The Barbed Wire Patent, 143 U.
S. 275;
Smith v. Goodyear Dental Vulcanite Co.,
93 U. S. 486.
The claim that the patentees of the patent in suit are not the
original discoverers of the process patented because an employee of
theirs happened to make the analyses and observations which
resulted immediately in the discovery cannot be allowed. The record
shows very clearly that the patentees planned the experiments in
progress when the discovery was made; that they directed the
investigations day by day, conducting them in large part
personally, and that they interpreted the results.
Agawam
Woolen Co. v. Jordan, 7 Wall. 583-603, rules this
claim against the defendant.
Equally untenable is the claim that the patent is invalid for
the reason that the evidence shows that, when different ores are
treated, preliminary tests must be made to determine the amount of
oil and the extent of agitation necessary in order to obtain the
best results. Such variation of treatment must be within the scope
of the claims, and the certainty which the law requires in patents
is not greater than is reasonable, having regard to their subject
matter.
Page 242 U. S. 271
The composition of ores varies infinitely, each one presenting
its special problem, and it is obviously impossible to specify in a
patent the precise treatment which would be most successful and
economical in each case. The process is one for dealing with a
large class of substances, and the range of treatment within the
terms of the claims, while leaving something to the skill of
persons applying the invention, is clearly sufficiently definite to
guide those skilled in the art to its successful application, as
the evidence abundantly shows. This satisfies the law.
Mowry v.
Whitney, 14 Wall. 620;
Ives v. Hamilton,
92 U. S. 426, and
Carnegie Steel Co. v. Cambria Iron Co., 185 U.
S. 403,
185 U. S.
436-437.
The evidence of infringement is clear.
While we thus find in favor of the validity of the patent, we
cannot agree with the district court in regarding it valid as to
all of the claims in suit. As we have pointed out in this opinion,
there were many investigators at work in this field to which the
process in suit relates when the patentees came into it, and it was
while engaged in study of prior kindred processes that their
discovery was made. While the evidence in the case makes it clear
that they discovered the final step which converted experiment into
solution, "turned failure into success" (
The Barbed Wire
Patent, 143 U. S. 275),
yet the investigations preceding were so informing that this final
step was not a long one, and the patent must be confined to the
results obtained by the use of oil within the proportions often
described in the testimony and in the claims of the patent as
"critical proportions," "amounting to a fraction of one percent on
the ore," and therefore the decree of this Court will be that the
patent is valid as to Claims No. 1, 2, 3, 5, 6, 7, and 12, and that
the defendant infringed these claims, but that it is invalid as to
Claims 9, 10, and 11. Claims No. 4, 8, and 13 were not considered
in the decrees of the two lower courts, and are not in issue in
this proceeding.
Page 242 U. S. 272
The decision of the circuit court of appeals will be
reversed, and the decision of the district court, modified to
conform to the conclusions expressed in this opinion, will be
affirmed.