1. Where it is improbable, notwithstanding the doubtful validity
of a patent, that conflict of decision respecting its validity will
arise in different circuits, because of the concentration in one
circuit of the industry in which the patented devices are used,
there is reason for granting certiorari to review a decision in
that circuit sustaining it. P.
305 U. S.
50.
2. A patent does not extend beyond the invention described and
explained as the statute requires; it cannot be enlarged by claims
in the patent not supported by the description. P.
305 U. S.
57.
3. The application for a patent cannot be broadened by amendment
so as to embrace an invention not described in the application as
filed, at least when adverse rights have intervened.
Powers-Kennedy Co. v. Concrete Co., 282 U.
S. 175;
Permutit Co. v. Graver Corporation,
284 U. S. 52.
Id.
4. Amendments to Patent No. 1,815,733, to Gulick, for a
combination in the structure of pistons of internal combustion
engines for automobiles, designed to prevent undue thermal
expansion of the pistons when in operation, were unlawfully added.
P.
305 U. S.
51.
5. In this combination, the head and skirt of the piston,
separated by an air space, are connected and held in proper
relation to each other by two webs which extend longitudinally
within the skirt and which, pierced at right angles for wrist-pin
bearings, support the piston pin bosses. The skirt is
longitudinally split in order to minimize the effects of thermal
expansion. The Circuit Court of Appeals regarded lateral
flexibility of the webs as an essential element of the invention.
The original application, however, contained no reference in terms
to laterally flexible webs or to the function of the webs in
securing flexibility of the skirt, but described the webs as
"extremely rigid," and stated that an object of the invention was
"to rigidly support the piston pin bosses from
Page 305 U. S. 48
the piston walls," and that the arrangement provided "a
particularly strong support for the bosses." The webs, as shown by
the drawings, conformed to these specifications, and neither
drawings nor specifications gave dimensions showing thickness or
other proportions of the webs which might suggest a flexible
structure.
Held:
(1) That, after a similar piston with the element of flexible
webs had come into commercial use and another had been described in
an application for patent, the patentee could not add that element
to his application by amendment. P.
305 U. S.
55.
(2) Amendments to that end could not be supported as being but
clarifications of the application as filed. P.
305 U. S.
57.
The contention that lateral flexibility was implied in the
original description as an inherent property of the metal composing
the web, and was disclosed by the drawings, is rejected.
Inherent flexibility of the web in cooperation with the slit
skirt cannot be depended upon to produce the desired effect in
rendering the skirt yieldable in response to cylinder wall
pressure. That depends upon design of the web, with correct
proportioning of the different parts as to location and thickness
to produce lateral flexibility. Inherent rigidity, made more
effective by design of the webs, would correspondingly curtail the
desired effect.
6. Decisions of the Court of Appeals for the District of
Columbia and the Court of Customs and Patent Appeals sustaining the
Gulick amendments are accorded weight, but are not controlling in
this Court when the validity of the amendments is involved in an
infringement case. P.
305 U. S.
59.
7. As flexible webs are neither described in the specifications
nor mentioned in the claims of the patent for a like combination to
Maynard, No. 1,655,968, they can be imported into them only by
reference to the drawings or by inference from the inherent
flexibility of the structure, which, as in the case of Gulick, are
insufficient to accomplish the result. P.
305 U. S.
60.
92 F.2d 330 reversed.
Certiorari, 304 U.S. 587, to review the reversal of a decree
holding certain patent claims invalid in suits for infringement.
Other patents, held invalid by the District Court but not passed
upon by the court below, were not involved in this review.
Page 305 U. S. 49
MR. JUSTICE STONE delivered the opinion of the Court.
The principal question for decision is whether the court below
rightly sustained the validity of two patents by including in the
combination constituting the alleged invention of each an element
which was not in terms described in one, and the description of
which in the other was added only by amendment to the application
after it was filed.
Respondent, the Cleveland Trust Company, is the assignee in
trust of some eighty patents relating to pistons of the type
employed in internal combustion engines for automobiles, under a
pooling agreement to which an automobile manufacturer and a number
of manufacturers of pistons are parties. It brought the present
suits in the District Court for Northern Ohio to enjoin
infringement of five of the assigned patents. The case was tried
before a special master who, upon the basis of elaborate findings,
held that the Gulick patent, No. 1,815,733, applied for November
30, 1917, and allowed July 31, 1931, was invalid for want of
invention and because of the addition to the application by
amendment in 1922 of a new element of the alleged invention. In
reaching this conclusion, he relied on this Court's decisions in
Powers-Kennedy Contracting
Corp. v. Concrete Mixing & Conveying Co.,
282
Page 305 U. S. 50
U.S. 175, and
Permutit Co. v. Graver Corporation,
284 U. S. 52, as
inconsistent with the result of interference proceedings in which
Gulick's amendments were sustained,
Long v. Gulick, 17
F.2d 686;
Hartog v. Long, 47 F.2d 369. The master also
held that the Maynard patent No. 1,655,968, applied for January 3,
1921, and allowed January 10, 1928, was invalid for want of
invention and for failure to describe and claim the alleged
invention. He held invalid upon various grounds the other patents,
which are not presently involved.
The District Court adopted the findings and conclusions of the
master and gave its decree for petitioners. The Circuit Court of
Appeals for the Sixth Circuit reversed, as to the Gulick and
Maynard patents only, holding that they were valid and infringed.
92 F.2d 330.** As the court regarded the claims which it sustained
as basic, and thought that a full recovery could be had by
respondent under them, it did not pass upon the validity of the
other patents or decide other questions involved in the appeal.
Petition for certiorari raising the question, among others,
whether the Circuit Court of Appeals had erred in holding
patentable a combination including one element not described in the
original application for the Gulick patent and later added to it by
amendment, and not described at all in the Maynard patent, was at
first denied, there being no conflict of decision. 303 U.S. 639. We
later granted certiorari, 304 U.S. 587, on a petition for rehearing
showing that, notwithstanding the doubtful validity of the patents,
litigation elsewhere with a resulting conflict of decision was
improbable because of the concentration of the automobile industry
in the Sixth Circuit.
Cf. Paramount Publix Corp. v. American
Tri-Ergon Corp., 294 U. S. 464;
Altoona Publix Theaters, Inc. v. American Tri-Ergon Corp.,
294 U. S. 477.
Page 305 U. S. 51
It is important for the proper functioning of the piston in a
gas engine that it should fit the explosion chamber closely, so as
to conserve power, prevent the passage of lubricating oil around
the piston into the chamber, and insure the smooth and noiseless
movement of the piston within the cylinder. In designing gas
engines for automobiles and other purposes requiring a high speed
piston reciprocation with the accompanying development of high
temperature in the explosion chamber, it is desirable to avoid
thermal expansion of the close fitting piston, which will result in
loss of power and possible injury to the mechanism through
increased friction, which may cause the piston to seize or stick.
The danger of undue expansion is increased when, as is advantageous
in automobile engines, the piston is of aluminum, which has a
higher coefficient of expansion than the iron or steel chamber
within which the piston moves.
Both the Gulick and Maynard patents are for combinations in the
structure of a piston for gas engines designed to prevent or
restrict undue expansion of the piston when in operation. The
Gulick patent exhibits a piston in which the ring-carrying head is
separated by an air space at its periphery from the cylindrically
shaped skirt or guide wall, whose surface engages the inner surface
of the cylinder. The piston head and skirt are connected by two
"webs" or walls extending longitudinally through the interior of
the skirt. The webs are pierced at right angles for wrist pin
bearings and support at the bearings, piston pin bosses formed with
integral flanges extending laterally from their respective bosses
to form the webs, which in turn are integrally connected on either
side with the interior wall of the lower part of the skirt and at
their ends with the piston head. The skirt is longitudinally split
on one side at a point in its circumference approximately midway
between the pin bosses, with the edges of the skirt formed by the
split separated so as
Page 305 U. S. 52
to admit of the free movement of the edges toward each
other.
The structure is thus designed to minimize the expansion
resulting from high temperatures developed in the chamber, and to
avoid the effects of thermal expansion of the skirt. The webs,
which afford at the wrist pin bearings the means for connecting the
piston rod with the piston, serve to hold the head and skirt in
proper relation to each other, so that the air space between them
retards flow of heat from the head to the skirt, undue expansion of
the skirt, and the consequent increase of friction between piston
and enveloping cylinder. Undue expansion of the piston is said by
the patent's specifications to be avoided by the separation of the
skirt by the longitudinal split in order to admit of unrestrained
movement of the edges of the skirt toward each other. Elsewhere,
they state that
"when the longitudinal split is used, as shown, the web
structure has sufficient lateral flexibility to permit the split to
close more or less under the action of the expansion forces
incident to the heating of the piston."
The elements of the combination as enumerated in Claim 39
are:
"A piston, open at one end, for an engine cylinder comprising a
skirt and head separated from the skirt wall around its entire
periphery, said skirt being longitudinally split to render the
skirt wall yieldable on every diameter in response to cylinder wall
pressure, wrist pin bosses, and means rigidly connecting said
bosses to the head and yieldingly connecting said bosses to the
skirt whereby said skirt is yieldable in response to cylinder wall
pressure."
Reference to a combination including, with other elements, web
connections, "whereby said piston skirt, is rendered yieldable
during operation in response to cylinder wall pressure," appears in
Claim 18.
The combination of piston head separated from a slitted skirt by
an air space, the two being connected by
Page 305 U. S. 53
webs supporting wrist pin bearings with bosses which do not come
directly in contact with the walls of the skirt, was plainly
foreshadowed by the prior art as a practicable means of minimizing
the flow of heat from head to skirt and of securing lateral
flexibility in the skirt. The expired Spillman and Mooers patent
No. 1,092,870, of April 14, 1914, pooled with the patents in suit,
showed a piston with head separated by an air space from the skirt,
the two being connected by a web separated from the skirt except at
the point of integral connection with it at the lower end of the
cylinder, and providing bearings for a wrist pin connection with
bosses not in direct contact with the wall of the skirt.
Flexibility of the skirt attained by longitudinal slits was old,
as shown by the Ebbs patent No. 700,309 of 1902, and Van Bever, No.
1,031,212 of 1912. The Franquist piston, patent No. 1,153,902 of
1915, another of the pooled patents, which showed piston head
partially separated from skirt by air spaces, attained flexibility
of the piston wall by longitudinal grooves in the skirt which
interrupted its outer periphery though connected at the inner edges
of the groove by a fold of the metal on the accordion principle.
The Long piston, patent No. 1,872,772 of 1932, which the master and
the District Court found was in commercial use from 1917 on, and
before the amendment of the Gulick application, presently to be
discussed, showed longitudinal slits cut through the skirt, which
was separated by air spaces from the piston head, the two being
connected by parallel webs pierced for wrist pin bearings.
The court below found invention in the Gulick disclosure in a
combination of elements, of which one was webs "laterally
flexible," which were not specifically so described in the Gulick
application until the amendment of 1922. Conceding that the
deceleration of the flow of heat from head to skirt by an air gap
might be an obvious
Page 305 U. S. 54
expedient of the art, and that to slit the skirt vertically so
as to compensate for thermal expansion might not be beyond the
skill of the art, the court added:
"But to combine insulation of head from skirt, retraction of the
bosses from the skirt periphery, connection of such bosses to the
skirt with webs laterally flexible and yet so carried from the head
as to support the load upon the wrist pin with sufficient strength
and rigidity, and to utilize the mechanical force of the cylinder
wall upon the skirt and the thermal expansion of the bosses so as
to compensate evenly and fully for head expansion and to secure a
balanced flexibility of the skirt with no bending concentration at
any point therein, discloses, we think, a meritorious concept
beyond the reach of those skilled in the art."
92 F.2d at 334.
We can find no support in the opinion for the contention of
respondent that the Circuit Court of Appeals did not consider the
flexible web an essential element in Gulick's invention. Its
enumeration, among other named elements, of the connection of head
and skirt by webs laterally flexible as embodying a meritorious
concept must be taken to indicate that the court regarded the
flexible webs as a part of the invention, the more so since it
indicates that lateral flexibility of the webs is the only feature
mentioned not within the prior art or within the expected skill of
the art. It rejected, on the authority of
Long v. Gulick,
supra, and
Hartog v. Long, supra, the contention made
below and pressed here that Gulick's application as filed did not
disclose "webs laterally flexible" and the resultant "balanced
flexibility of the skirt," and that those features were added to
specifications and claims after the use of the Long piston and
after they had appeared in Hartog.
The Gulick application, which was filed November 30, 1917,
contained no reference in terms to laterally flexible webs or to
the function of the webs in securing flexibility
Page 305 U. S. 55
of the skirt. The specifications pointed to no inadequacy in the
structure or function of webs of the prior art which would be
remedied by the webs specified and to no function to be performed
by them other than as a means of connecting and holding head and
skirt so as to maintain the air gap between them and to support the
wrist pin bearings and their bosses as both were shown in Spillman
and Mooers. On the contrary, Gulick's application described the
webs as "extremely rigid," and stated that an object of the
invention was "to rigidly support the piston pin bosses of a piston
from the piston walls." The only description of the web structure
was as follows:
"It will be seen that, in addition to providing a piston with a
split skirt, the above-described construction also provides an
extremely rigid connection between the piston pin bosses and the
skirt of the piston, which construction may be used either with or
without the split skirt and separated head. The arrangement of the
supporting flanges 17 between the ends of the piston pin bosses and
the connection of those flanges with the piston skirt provide a
particularly strong support for the bosses."
The webs as shown by the drawings conform to the specifications
of an "extremely rigid connection" between piston pin bosses and
skirt, and "a particularly strong support for the bosses." They
form chords subtending the are of the circle of the skirt, with
flanges depending from the head to the bosses at right angles to
the webs, and the skirt as shown is provided with interior
corrugations and with an in-turned flange at the bottom, all
familiar devices for securing rigidity of structure. Neither
drawings nor specifications give dimensions showing thickness or
other proportions which might suggest a flexible structure.
In 1922, after the Long piston, whose webs concededly were
laterally flexible, was in commercial use, and Hartog, to the
knowledge of Gulick's assignee, had specified and
Page 305 U. S. 56
claimed a yieldable web, Gulick copied the Hartog claim and
amended his specifications so as to state that one of the objects
of his invention was
"to rigidly support the piston pin bosses of a piston from the
piston wall against mechanical load thrust from the connecting rod
without interfering with the yielding characteristics of the skirt
in response to cylinder wall pressure."
And he amended his description of the web structure to read:
"The arrangement of the supporting flanges 17 between the ends
of the piston pin bosses and the connections of those flanges with
both the piston guide portion and the head provide a particularly
strong construction, and at the same time, when the longitudinal
split is used, as shown, the web structure has sufficient lateral
flexibility to permit the split to close more or less under the
action of the expansion forces incident to the heating of the
piston."
Petitioners insist that the flexible web element of the Gulick
combination, as found and sustained by the court below, is excluded
from the Gulick patent by reason of his failure to describe that
element in his application as filed, and that he could not cure the
omission and secure a patent embodying that feature by substituting
by way of amendment "webs laterally flexible" for "extremely rigid
webs" in the description of his invention. The statute, R.S. ยง
4888, provides that the application which the inventor must file as
a prerequisite to a patent shall contain
"a written description of [his invention] . . . and of the
manner and process of making, constructing . . . and using it, in
such full, clear, concise, and exact terms as to enable any person
skilled in the art . . . to . . . construct . . . and use the same,
and, in case of a machine, he shall explain the principle thereof,
and the best mode in which he has contemplated applying that
principle, so as to distinguish it from other inventions. . . .
"
Page 305 U. S. 57
The object of the statute is to require the patentee to describe
his invention so that others may construct and use it after the
expiration of the patent, and
"to inform the public during the life of the patent of the
limits of the monopoly asserted, so that it may be known which
features may be safely used or manufactured without a license and
which may not."
Permutit Co. v. Graver Corporation, 284 U. S.
52,
284 U. S. 60. It
follows that the patent monopoly does not extend beyond the
invention described and explained as the statute requires,
Permutit Co. v. Graver Corporation, supra at
284 U. S. 57;
that it cannot be enlarged by claims in the patent not supported by
the description,
Snow v. Lake Shore & M.S. Ry. Co.,
121 U. S. 617;
cf. Smith v. Snow, 294 U. S. 1, and
that the application for a patent cannot be broadened by amendment
so as to embrace an invention not described in the application as
filed, at least when adverse rights of the public have intervened.
Chicago & N.W. Ry. Co. v. Sayles, 97 U. S.
554,
97 U. S.
563-564;
Powers-Kennedy Contracting Corp. v.
Concrete Mixing & Conveying Co., 282 U.
S. 175,
282 U. S.
185-186;
cf. Webster Electric Co. v. Splitedorf
Electrical Co., 264 U. S. 463;
Permutit Co. v. Graver Corporation, supra; Crown Cork &
Seal Co. v. Gutmann Co., 304 U. S. 159.
Respondent earnestly argues, as both courts held in the
interference proceedings,
Long v. Gulick, supra, and
Hartog v. Long, supra, that the changes in Gulick's
application were not alterations in the description of his
invention, but were, at most, a permissible clarification of its
description of the flexible web element which was present, or at
least plainly suggested, in the specifications and drawings of the
Gulick application. Flexibility, it is said, as is well known to
those skilled in the art, is an inherent property of the metal out
of which the webs are made, and, in consequence, reference to the
webs in the application as filed was sufficient to import into it
as a part of the description of the invention their known quality
of
Page 305 U. S. 58
flexibility, a description which was made more specific, but not
altered, by the amendments. The argument suggests that it was but
the skill of the art, and not invention, to substitute a flexible
for a rigid means of connecting head and skirt in a known
combination of piston head separated from a slitted skirt by an air
space and connected by webs. But, in any case, we think it falls
short of establishing that the Gulick amendments were not new
matter beyond the scope of the device described in the application
as filed.
The properties of any given material are many and diverse. The
antithetical qualities of rigidity and flexibility of a structure
are not absolute, but relative; it may be more rigid than some and
more flexible than others; too rigid for some purposes and too
flexible for others. The one quality may be increased and the other
diminished by choice of materials from which the structure is made
and by variation in its proportions. If invention depends on
emphasis of one quality over the other, as the court below found
was the case with the laterally flexible webs in the Gulick devise,
the statute requires that emphasis to be revealed to the members of
the public, who are entitled to know what invention is claimed.
That is not accomplished either by naming a member having inherent
antithetical properties or by ascribing to it one property when the
other is meant. Since rigidity is a relative term, the
characterization of the structure as rigid must be taken as
emphasizing rigidity, rather than its opposite, flexibility, with
special reference to the conditions to be encountered in the
operation of the piston. Even if those skilled in the art would
have known that a piston with webs which would yield enough
laterally to accommodate the constriction of the split skirt under
the pressure developed by thermal expansion would work most
effectively if the webs were laterally flexible, rather than
Page 305 U. S. 59
rigid, that was not the invention which Gulick described by his
references to an extremely rigid web.
Gulick also failed to explain the principle of his machine so as
to distinguish it from the prior art. Webs having the inherent
properties both of rigidity and flexibility were familiar elements
in piston structure. The court below, after pointing out that the
slots of the Franquist skirt rendered it capable of limited
construction, found a distinguishing feature of Gulick's piston to
be a web relatively flexible laterally, so as to accommodate the
constriction of skirt to thermal expansion, the combination
operating to secure a "balanced flexibility" of the skirt. But that
principle -- facilitating skirt constriction, rather than
obstructing it -- was first explained, and its embodiment in the
flexible-webbed device was first claimed, by the amendments to the
application.
As already indicated, the omission from the specifications was
not supplied by the drawings, which failed to disclose by
dimensions the proportions of the webs. Inherent flexibility of the
web in cooperation with the slit skirt cannot be depended upon to
produce the desired effect in rendering the skirt yieldable in
response to cylinder wall pressure. As respondent's own expert
testified, that depends upon design of the web, with correct
proportioning of the different parts as to location and thickness
to produce lateral flexibility. Inherent rigidity, made more
effective by design of the webs, would correspondingly curtail the
desired effect.
We recognize the weight to be attached to the determinations in
the interference proceedings in which the Court of Appeals of the
District of Columbia and the Court of Customs and Patent Appeals
sustained the Gulick amendments.
Cf. Radio Corp. v. Radio
Engineering Laboratories, 293 U. S. 1,
293 U. S. 7. But
the decisions in those cases are not controlling here. So far as
the courts relied on
Page 305 U. S. 60
the inherent flexibility of the webs to supply the feature of
lateral flexibility omitted from the Gulick description they
ignored the principle recognized in
Permutit Co. v. Graver
Corporation, supra, and
Powers-Kennedy Contracting Corp.
v. Concrete Mixing & Conveying Co., supra. So far as they
relied on the drawings to supply the omission they disregarded the
fact shown both by inspection and by the evidence presented here
that the drawings do no more to point to Gulick's invention than
does the fact of inherent flexibility. We conclude that respondent
can take no benefit from the flexible web element added by
amendment to the Gulick application.
In sustaining the claims of the Maynard patent, the court below
said that
"Maynard . . . embodies the Gulick combination of skirt
insulation, skirt flexibility by means of vertical slotting
cooperating with longitudinal slotting, and flexible webs in the
region of the wrist pin bosses. He also follows Jardine's
simplified design to permit economical manufacture and Jardine's
boss relief,"
and, after enumerating certain mechanical features of the
Maynard construction differing from Gulick and Jardine,
concluded:
"It is clear that Maynard, while not departing from the teaching
of Gulick in basic combination of elements, discloses a piston
lighter and more economical of manufacture than Gulick and one more
rugged and durable than Jardine."
92 F.2d at 337.
Invention over Gulick and Jardine was apparently found in the
details of construction, but, as we are without other indication of
the character of the invention, we construe the court's opinion as
including the laterally flexible webs as an essential element in
the patented combination. As flexible webs are neither described in
Maynard's specifications nor mentioned in his claims, they can be
imported into them only by reference to the drawings or by
inference from the inherent flexibility of the structure, which,
for reasons already given in our consideration
Page 305 U. S. 61
of the Gulick amendments, are insufficient to accomplish that
result. We conclude that the court below erred in giving any effect
to so much of the Gulick patent as by amendment describes or claims
the flexible webs, and in treating any of the specifications or
claims in Gulick and Maynard as referring to such webs. We assume
that it sustained Claim 1 of the Gulick patent, which makes no
mention of web flexibility, only by reading into it that element,
which the court regarded as an essential part of the invention.
As the Circuit Court of Appeals did not pass upon other
questions in the case, the causes will be reversed and remanded to
it for further proceedings, in conformity with this opinion, with
respect to such claims of the patents in suit as appellant below
submitted to that court for adjudication.
Reversed.
MR. JUSTICE ROBERTS took no part in the consideration or
decision of this case.
* Together with No. 4,
Aberdeen Motor Supply Co. v.
Cleveland Trust Co. et al., and No. 5,
F. E. Rowe Sales
Co. v. Cleveland Trust Co. et al., also on writs of certiorari
to the Circuit Court of Appeals for the Sixth Circuit.
** The decree sustained Gulick's claims numbered 1, 11, 12, 13,
15, 18, 30 and 33, and Maynard's claims numbered 1, 6 and 8.