A patent was taken out for making the body of a burden railroad
car of sheet iron, the upper part being cylindrical, and the lower
part in the form of a frustum of a cone, the under edge of which
has a flange secured upon it, to which flange a movable bottom is
attached.
The claim was this.
"What I claim its my invention and desire to secure by letters
patent is making the body of a car for the transportation of coal
&c., in the form of a frustum of a cone, substantially as
herein described, whereby the force exerted by the weight of the
load presses equally in all directions and does not tend to change
the form thereof, so that every part resists its equal proportion,
and by which also the lower part is so reduced as to pass down
within the truck frame and between the axles to lower the center of
gravity of the load without diminishing the capacity of the car as
described. I also claim extending the body of the car below the
connecting pieces of the truck frame and the line of draft, by
passing the connecting bars of the truck frame and the draft bar,
through the body of the car substantially described."
This patent was not for merely changing the form of a machine,
but by means of such change to introduce and employ other
mechanical principles or natural powers, or a new mode of
operation, and thus attain a new and useful result.
Hence, where, in a suit brought by the patentee against persons
who had constructed octagonal and pyramidal cars, the district
judge ruled that the patent was good for conical bodies, but not
for rectilinear bodies, this ruling was erroneous.
The structure, the mode of operation, and the result attained
were the same in both, and the specification claimed in the patent
covered the rectilinear cars. With this explanation of the patent,
it should have been left to the jury to decide the question of
infringement as a question of fact.
This was an action brought by Ross Winans for the infringement
of a patent right. The jury, under the instruction of the district
judge, the late Judge Glenn, then sitting alone, found a verdict
for the defendants, and the plaintiff brought the case to this
Court by a writ of error.
The nature of the case is set forth in the explanatory statement
prefixed to the argument of the counsel for the plaintiff in
error.
Page 56 U. S. 338
MR. JUSTICE CURTIS delivered the opinion of the Court.
This is a writ of error to the Circuit Court of the United
States for the District of Maryland. The plaintiff in error brought
his action in that court for an infringement of the exclusive right
to make, use, and sell "an improvement in cars for the
transportation of coal," &c., granted to him by letters patent,
bearing date on the 26th day of June, 1847, and, the judgment of
that court being for the defendants, he has brought the record here
by this writ of error.
It appears, by the bill of exceptions, that the letters patent
declared on were duly issued, and that their validity was not
questioned, but the defendants denied that they had infringed upon
the exclusive right of the plaintiff.
On such a trial, two questions arise. The first is what is the
thing patented; the second, has that thing been constructed, used,
or sold by the defendants.
The first is a question of law, to be determined by the court
construing the letters patent, and the description of the invention
and specification of claim annexed to them. The second is a
question of fact, to be submitted to a jury.
In this case, it is alleged the court construed the
specification of claim erroneously, and thereby withdrew from the
jury questions which it was their province to decide. This renders
it necessary to examine the letters patent, and the schedule
annexed to them, to see whether their construction by the circuit
court was correct.
In this, as in most patent cases, founded on alleged
improvements in machines, in order to determine what is the thing
patented, it is necessary to inquire.
1. What is the structure or device, described by the patentee,
as embodying his invention.
2. What mode of operation is introduced and employed by this
structure or device.
3. What result is attained by means of this mode of
operation.
Page 56 U. S. 339
4. Does the specification of claim cover the described mode of
operation by which the result is attained.
Without going into unnecessary details, or referring to
drawings, it may be stated that the structure, described by this
patent, is the body of a burden railroad car, made of sheet iron,
the upper part being cylindrical, and the lower part in the form of
a frustum of a cone, the under edge of which has a flange secured
upon it, to which flange a movable bottom is attached. This bottom
is made movable, in order to discharge the load through the
aperture left by removing it.
To understand the mode of operation introduced and employed by
means of this form of the car body, it is only necessary to state,
what appears on the face of the specification, and was testified to
by experts at the trial as correct, that, by reason of the circular
form of the car body, the pressure of the load outwards was equal
in every direction, and thus the load supported itself in a great
degree; that by making the lower part conical, this principle of
action operated throughout the car, with the exception of the small
space to which the movable bottom was attached; that, being
conical, the lower part of the car could be carried down below the
truck, between the wheels, thus lowering the center of gravity of
the load; that the pressure outwards upon all parts of the circle
being equal, the tensile strength of the iron was used to a much
greater degree than in a car of a square form; and, finally, that
this form of the lower part of the car facilitated the complete
discharge of the load through the aperture, when the bottom was
removed.
It thus appears that, by means of this change of form, the
patentee has introduced a mode of operation not before employed in
burden cars, that is to say, nearly equal pressure in all
directions by the entire load, save that small part which rests on
the movable bottom; the effects of which are that the load, in a
great degree, supports itself, and the tensile strength of the iron
is used, while at the same time, by reason of the same form, the
center of gravity of the load is depressed, and its discharge
facilitated.
The practical result attained this mode of operation is
correctly described by the patentee, for the uncontradicted
evidence at the trial showed that he had not exaggerated the
practical advantage of his invention. The specification states:
"The transportation of coal, and all other heavy articles in
lumps, has been attended with great injury to the cars, requiring
the bodies to be constructed with great strength to resist the
outward pressure on the sides, as well as the vertical pressure on
the bottom, due not only to the weight of the mass, but the
mobility of the lumps among each other tending to 'pack,' as
Page 56 U. S. 340
it is technically termed. Experience has shown that cars, on the
old mode of construction, cannot be made to carry a load greater
than its own weight; but, by my improvement, I am enabled to make
cars of greater durability than those heretofore made, which will
transport double their own weight of coal,"
&c.
Having thus ascertained what is the structure described, the
mode of operation it embodies, and the practical result attained,
the next inquiry is, does the specification of claim cover this
mode of operation, by which this result is effected?
It was upon this question the case turned at the trial in the
circuit court.
The testimony showed that the defendants had made cars similar
to the plaintiff's, except that the form was octagonal instead of
circular. There was evidence tending to prove that, considered in
reference to the practical uses of such a car, the octagonal car
was substantially the same as the circular. Amongst other witnesses
upon this point was James Millholland, who was called by the
defendants. He testified.
"That the advantage of a reduced bottom of the car was obtained,
whether the car was conical or octagonal; that the strengthening of
the bottom, due to the adoption of a conical form, was the same
when the octagonal form was adopted, or the circular. That the
circular form was the best to resist the pressure, as, for
instance, in a steam boiler, and an octagonal one better than the
square form; that the octagonal car was not better than the conical
car; that, for practical purposes, one was as good as the other;
that a polygon of many sides would be equivalent to a circle; that
the octagon car, practically, was as good as the conical ones; and
that, substantially, the witness saw no difference between the
two."
The district judge, who presided at the trial, ruled:
"That while the patent is good for what [is] described therein,
a conical body, in whole or in part, supported in any of the modes
indicated for a mode of sustaining a conical body on a carriage or
truck, and drawing the same, and to those principles which were due
alone to conical vehicles, and not to rectilinear bodies, and it
being admitted that the defendants' car was entirely rectilinear,
that there was no infringement of the plaintiff's patent."
The substance of this ruling was that the claim was limited to
the particular geometrical form mentioned in the specification, and
as the defendants had not made cars in that particular form, there
could be no infringement, even if the cars made by the defendants
attained the same result by employing what was in fact the same
mode of operation as that described by the patentee. We think this
ruling was erroneous.
Page 56 U. S. 341
Under our law a patent cannot be granted merely for a change of
form. The Act of February 21, 1793, § 2, so declared in express
terms; and though this declaratory law was not reenacted in the
Patent act of 1836, it is a principle which necessarily makes part
of every system of law granting patents for new inventions. Merely
to change the form of a machine is the work of a constructor, not
of an inventor; such a change cannot be deemed an invention. Nor
does the plaintiff's patent rest upon such a change. To change the
form of an existing machine, and by means of such change to
introduce and employ other mechanical principles or natural powers,
or, as it is termed, a new mode of operation, and thus attain a new
and useful result, is the subject of a patent. Such is the basis on
which the plaintiff's patent rests.
Its substance is a new mode of operation, by means of which a
new result is obtained. It is this new mode of operation which
gives it the character of an invention, and entitles the inventor
to a patent; and this new mode of operation is, in view of the
patent law, the thing entitled to protection. The patentee may, and
should, so frame his specification of claim as to cover this new
mode of operation which he has invented; and the only question in
this case is whether he has done so, or whether he has restricted
his claim to one particular geometrical form.
There being evidence in the case tending to show that other
forms do in fact embody the plaintiff's mode of operation, and, by
means of it, produce the same new and useful result, the question
is whether the patentee has limited his claim to one out of the
several forms which thus embody his invention.
Now while it is undoubtedly true, that the patentee may so
restrict his claim as to cover less than what he invented, or may
limit it to one particular form of machine, excluding all other
forms, though they also embody his invention, yet such an
interpretation should not be put upon his claim if it can fairly be
construed otherwise, and this for two reasons:
1. Because the reasonable presumption is that, having a just
right to cover and protect his whole invention, he intended to do
so.
Haworth v. Hardcastle, Web.P.C.484.
2. Because specifications are to be construed liberally, in
accordance with the design of the Constitution and the patent laws
of the United States, to promote the progress of the useful arts,
and allow inventors to retain to their own use, not anything which
is matter of common right, but what they themselves have created.
Grant v.
Raymond, 6 Pet. 218;
Ames v. Howard, 1
Sumn. 482, 485;
Blanchard v. Sprague, 3 Sumn. 535, 539;
Davoll v. Brown, 1 Wood. & Minot 53, 57;
Parker
v.
Page 56 U. S. 342
Haworth, 4 McLean 372;
Le Roy
v. Tatham, 14 How. 181, and opinion of Parke,
Baron, there quoted;
Neilson v. Harford, Web.P.C. 341;
Russell v. Cowley, id., 470;
Burden v. Winslow,
decided at the present term, 15 How.
The claim of the plaintiff is in the following words:
"What I claim as my invention, and desire to secure by letters
patent, is making the body of a car for the transportation of coal
&c., in the form of a frustum of a cone, substantially as
herein described, whereby the force exerted by the weight of the
load presses equally in all directions, and does not tend to change
the form thereof, so that every part resists its equal proportion,
and by which, also, the lower part is so reduced as to pass down
within the truck frame and between the axles, to lower the center
of gravity of the load without diminishing the capacity of the car
as described."
"I also claim extending the body of the car below the connecting
pieces of the truck frame, and the line of draft, by passing the
connecting bars of the truck frame, and the draft bar, through the
body of the car, substantially as described."
It is generally true, when a patentee describes a machine and
then claims it as described, that he is understood to intend to
claim, and does by law actually cover, not only the precise forms
he has described, but all other forms which embody his invention,
it being a familiar rule that to copy the principle or more of
operation described is an infringement, although such copy should
be totally unlike the original in form or proportions.
Why should not this rule be applied to this case?
It is not sufficient to distinguish this case to say that here
the invention consists in a change of form, and the patentee has
claimed one form only.
Patentable improvements in machinery are almost always made by
changing someone or more forms of one or more parts, and thereby
introducing some mechanical principle or mode of action not
previously existing in the machine, and so securing a new or
improved result. And, in the numerous cases in which it has been
held, that to copy the patentee's mode of operation was an
infringement, the infringer had got forms and proportions not
described, and not in terms claimed. If it were not so, no question
of infringement could arise. If the machine complained of were a
copy, in form, of the machine described in the specification, of
course it would be at once seen to be an infringement. It could be
nothing else. It is only ingenious diversities of form and
proportion, presenting the appearance of something unlike the thing
patented, which give rise to questions, and the property of
inventors would be valueless if it
Page 56 U. S. 343
were enough for the defendant to say, "your improvement
consisted in a change of form; you describe and claim but one form;
I have not taken that, and so have not infringed."
The answer is
"my improvement did not consist in a change of form, but in the
new employment of principles or powers, in a new mode of operation,
embodied in a form by means of which a new or better result is
produced; it was this which constituted my invention; this you have
copied, changing only the form; and that answer is justly
applicable to this patent."
Undoubtedly there may be cases in which the letters patent do
include only the particular form described and claimed.
Davis
v. Palmer, 2 Brock. 309, seems to have been one of those
cases. But they are in entire accordance with what is above
stated.
The reason why such a patent covers only one geometrical form,
is not that the patentee has described and claimed that form only;
it is because that form only is capable of embodying his invention,
and consequently, if the form is not copied, the invention is not
used.
Where form and substance are inseparable, it is enough to look
at the form only. Where they are separable; where the whole
substance of the invention may be copied in a different form, it is
the duty of courts and juries to look through the form for the
substance of the invention -- for that which entitled the inventor
to his patent, and which the patent was designed to secure; where
that is found, there is an infringement; and it is not a defense,
that it is embodied in a form not described, and in terms claimed
by the patentee.
Patentees sometimes add to their claims an express declaration,
to the effect that the claim extends to the thing patented, however
its form or proportions may be varied. But this is unnecessary. The
law so interprets the claim without the addition of these words.
The exclusive right to the thing patented is not secured, if the
public are at liberty to make substantial copies of it, varying its
form or proportions. And therefore the patentee, having described
his invention, and shown its principles, and claimed it in that
form which most perfectly embodies it, is, in contemplation of law,
deemed to claim every form in which his invention may be copied,
unless he manifests an intention to disclaim some of those
forms.
Indeed it is difficult to perceive how any other rule could be
applied, practicably, to cases like this. How is a question of
infringement of this patent to be tried? It may safely be assumed
that neither the patentee nor any other constructer has made or
will make a car exactly circular. In practice, deviations from a
true circle will always occur. How near to a
Page 56 U. S. 344
circle, then, must a car be in order to infringe? May it be
slightly elliptical, or otherwise depart from a true circle, and,
if so, how far?
In our judgment, the only answer that can be given to these
questions is that it must be so near to a true circle as
substantially to embody the patentee's mode of operation, and
thereby attain the same kind of result as was reached by his
invention. It is not necessary that the defendant's cars should
employ the plaintiff's invention to as good advantage as he
employed it, or that the result should be precisely the same in
degree. It must be the same in kind, and effected by the employment
of his mode of operation in substance. Whether in point of fact the
defendant's cars did copy the plaintiff's invention in the sense
above explained is a question for the jury, and the court below
erred in not leaving that question to them upon the evidence in the
case, which tended to prove the affirmative.
The judgment of the court below must be
Reversed.
MR. CHIEF JUSTICE TANEY, MR. JUSTICE CATRON, MR. JUSTICE DANIEL,
and MR. JUSTICE CAMPBELL, dissented.
MR. JUSTICE CAMPBELL.
I dissent from the opinion of the Court in this case.
The plaintiff claims to have designed and constructed a car for
the transportation of coal on railroads which shall carry the
heaviest load in proportion to its own weight.
His design consists in the adoption of the "conical form" "for
the body of the car," "whereby the weight of the load presses
equally in all directions," does not "tend to change the form of
the car," permits it "to extend down within the truck," lowering
"the center of gravity of the load," and by its reduced size at the
bottom adding to its strength and durability. He claims as his
invention, and it is the whole of the change which he has made in
the manufacture of cars, "the making of the body of the car in the
form of the frustum of a cone."
It is agreed that a circle contains a greater area than any
figure of the same perimeter, that the conical form is best suited
to resist pressure from within, and that the reduced size at the
bottom of the car is favorable to its strength. The introduction of
the cars of the plaintiff upon the railroad for the transportation
of coal was attended by a great increase of the loads in proportion
to the weight of the car. The merits of the design are frankly
conceded. Nevertheless it is notorious that there does exist a very
great variety of vessels in common domestic use "of a conical
form," or, "of the form of the frustum of a cone," for the
reception and transportation of articles of prime
Page 56 U. S. 345
necessity and constant demand, such as water, coal, food,
clothing &c. It is also true that the properties of the circle
and of circular forms alluded to in the patent of the plaintiff are
understood and appreciated, and have been applied in every
department of mechanic art. One cannot doubt that a requisition
from the transportation companies for cars of a diminished weight
and an increased capacity upon the machinists and engineers
connected with the business would have been answered promptly by a
suggestion of a change in the form of the car. The merit of the
plaintiff seems to consist in the perfection of his design, and his
clear statement of the scientific principle it contains.
There arises in my mind a strong if not insuperable objection to
the admission of the claim in the patent for "the conical form" or
the form of the "frustum of a cone" as an invention. Or that any
machinist or engineer can appropriate by patent a form whose
properties are universally understood and which is in very common
use, in consequence of those properties, for purposes strictly
analogous. The authority of adjudged cases seems to me strongly
opposed to the claim.
Hotchkiss v.
Greenwood, 11 How. 249;
Losh v. Hague,
Web.Pat.Cas. 207;
Winans v. Providence Railroad Company, 2
Story 412; 2
id. 190; 2 Car. & Kir. 1022; 3 W.H. &
Gord. 427.
Conceding, however, that the invention was patentable, and this
seems to have been conceded in the circuit court, the inquiry is,
what is the extent of the claim? The plaintiff professes to have
made an improvement in the form of a vehicle, which has been a long
time in use, and exists in a variety of forms. He professes to have
discovered the precise form most fitted for the objects in view. He
describes this form, as the matter of his invention, and the
principle he develops applies to no other form. For this he claims
his patent. We are authorized to conclude, that his precise and
definite specification and claim were designed to ascertain exactly
the limits of his invention.
Davis v. Palmer, 2 Brock.
298.
The car of the defendants is of an octagonal form, with an
octagonal pyramidical base. There was no contradiction, in the
evidence given at the trial, in reference to its description, nor
as to the substantial effects of its use and operation. In the
size, thickness of the metal employed in its construction, weight,
and substantial and profitable results, the one car does not
materially vary from the other. The difference consists in the
form, and in that, it is visible and palpable.
The circuit court, acting upon these facts, of which there was
no dispute, instructed the jury that an infringement of the
plaintiff's patent had not taken place. I do not find the
Page 56 U. S. 346
question before the court a compound question of law and fact.
The facts were all ascertained, and upon no construction of those
facts was the plaintiff, in my opinion, entitled to a judgment.
In theory, the plaintiff's car is superior to all others. His
car displays the qualities which his specification distinguishes.
The equal pressure of the load in all directions; the tendency to
preserve the form, notwithstanding the pressure of the load; the
absence of the cross strain; the lowering of the center of the
gravity of the load -- are advantages which it possesses in a
superior degree to that of the defendants'. Yet the experts say
that there is no appreciable difference in the substantial results
afforded by the two.
The cause for this must be looked for in a source extrinsic to
the mere form of the vehicles. Nor is it difficult to detect the
cause for this identity in the results in such a source.
The coarse, heavy, cumbrous operations of coal transportation do
not admit of the manufacture of cars upon nice mathematical
formulas, nor can the loads be adjusted with much reference to
exactness. There is a liability to violent percussion's and
extraordinary strains, which must be provided for by an excess in
the weight and thickness of the material used. Then, unless the
difference in the weight of the load is great, there will be no
correspondent difference in the receipts of the transportation
companies.
The patentee, not exaggerating the theoretical superiority of
the form of his car, overlooked those facts which reduced its
practical value to the level of cars of a form widely variant from
his own. The object of this suit is to repair that defect of
observation. It is that this Court shall extend, by construction,
the scope and operation of his patent, to embrace every form which
in practice will yield a result substantially equal or approximate
to his own.
In the instruction asked for by the plaintiff, "form and
circumstances" are treated as more or less immaterial, but the
verdict is claimed if the defendants have constructed cars "which,
substantially on the same principle and in the same mode of
operation, accomplish the same result."
The principle stated in the patent applies only to circular
forms.
The modes of operation in coal transportation have experienced
no change from the skill of the plaintiff, except by the change
from the rectilinear figure to the circular.
The defendant adheres to the rectilinear form. The result
accomplished by the use of the two cars is the same -- a more
economical transportation of coal. This result it is that the
Page 56 U. S. 347
plaintiff desires to appropriate, but this cannot be permitted.
Curtis on Patents, § 4, 26, 27, 86, 87, 88; 2 Story 408, 411.
In the case of
Aiken v. Bemis, 3 Wood. & M. 349,
the learned judge said,
"When a patentee chooses to cover with his patent the material
of which a part of his machine is composed, he entirely endangers
his right to prosecute when a different and inferior material is
employed, and one which he himself, after repeated experiment, had
rejected."
The plaintiff confines his claim to the use of the conical form,
and excludes from his specification any allusion to any other. He
must have done so advisedly. He might have been unwilling to expose
the validity of his patent, by the assertion of a right to any
other. Can he abandon the ground of his patent, and ask now, for
the exclusive use of all cars which, by experiment, shall be found
to yield the advantages which he anticipated for conical cars
only?
The claim of today is that an octagonal car is an infringement
of this patent. Will this be the limit to that claim? Who can tell
the bounds within which the mechanical industry of the country may
freely exert itself? What restraints does this patent impose in
this branch of mechanic art?
To escape the incessant and intense competition which exists in
every department of industry, it is not strange that persons should
seek the cover of the patent act, for any happy effort of
contrivance or construction, nor that patents should be very
frequently employed to obstruct invention, and to deter from
legitimate operations of skill and ingenuity. This danger was
foreseen and provided for in the patent act. The patentee is
obliged by law to describe his invention, in such full, clear, and
exact terms that from the description the invention may be
constructed and used. Its principle and modes of operation must be
explained, and the invention shall particularly "specify and point"
out what he claims as his invention. Fullness, clearness,
exactness, preciseness, and particularity in the description of the
invention, its principle, and of the matter claimed to be invented
will alone fulfill the demands of Congress or the wants of the
country. Nothing in the administration of this law will be more
mischievous, more productive of oppressive and costly litigation,
of exorbitant and unjust pretensions and vexations demands, more
injurious to labor than a relaxation of these wise and salutary
requisitions of the act of Congress. In my judgment, the principles
of legal interpretation as well as the public interest require that
this language of this statute shall have its full significance and
import.
In this case, the language of the patent is full, clear, and
exact. The claim is particular and specific.
Page 56 U. S. 348
Neither the specification nor the claim, in my opinion, embraces
the workmanship of the defendants. I therefore respectfully dissent
from the judgment of the Court, which implies the contrary.
Order
This cause came on to be heard on the transcript of the record
from the Circuit Court of the United States for the District of
Maryland and was argued by counsel. On consideration whereof it is
now here ordered and adjudged by this Court that the judgment of
the said circuit court in this cause be and the same is hereby
reversed with costs, and that this cause be and the same is hereby
remanded to the said circuit court with directions to award a
venire facias
de novo.