Where, before the issue of letters patent therefor, a party
assigns his invention, and letters are lawfully issued to the
assignee in his own name, the latter is entitled, where the
instrument of assignment does not show a different intention, to
obtain a renewal of them at the expiration of the original
Lafayette F. Thompson and Asahel G. Bachelder, claiming to be
inventors of a railroad brake, executed, before letters patent were
issued to them therefore, the following assignment, which was duly
recorded in the Patent Office:
"Whereas we, Lafayette F. Thompson, of Charlestown, and Asahel
G. Bachelder, now or late of Lowell, in the State of Massachusetts,
have invented an improved mode of operating the brakes of railway
cars, and have applied, or intend to apply, for letters patent of
the United States of America therefor."
"Now, therefore, this indenture witnesseth, that for and in
consideration of $100, in hand paid, the receipt whereof is hereby
acknowledged, I have assigned and set over, and do hereby assign,
sell, and set over, to Henry Tanner, of Buffalo, in the State of
New York, all the right, title, and interest whatever which we now
have, or by letters patent would be entitled to have and possess,
in the aforesaid invention, the said invention being described in
the specification as prepared and executed by us, or to be prepared
and executed by us, for the obtaining of said letters patent; the
whole to be enjoyed and held by the said Henry Tanner and his legal
representatives, to the full extent and manner in which the same
should have been or could be held and enjoyed by us had this
assignment never been made."
"And we do, by these presents, authorize the Commissioner of
Patents to issue the said letters patent to the said Henry
Page 98 U. S. 547
and his legal representatives, as the assignee of our whole
right and title to the same and to the new invention
"In witness whereof, we have hereto set our signatures and
seals, this first day of April, A.D. 1852."
"LAFAYETTE F. THOMPSON [SEAL]"
"ASAHEL G. BACHELDER [SEAL]"
"Witness, R. H. EDDY"
Letters patent were issued on the sixth day of the following
July to Tanner, who, July 13, 1854, assigned to Thomas Sayles all
his remaining right and title in them for the unexpired term
thereof, and "any extension thereof that may hereafter be granted,"
excepting, however, certain reserved territory and specified
railroad corporations. Said letters were renewed and extended for
seven years from July 6, 1866.
After that date, and until some time in 1873, Hendrie infringed
the patents within the territory not so reserved, and Sayles filed
his bill for an account &c., to which Hendrie demurred, upon
the ground that Sayles had no legal title to the extended term. The
demurrer was overruled, and a decree for want of an answer passed
for the complainant. Hendrie thereupon appealed here.
Page 98 U. S. 548
MR. JUSTICE CLIFFORD delivered the opinion of the Court.
Patents or any interest therein may be assigned by an instrument
in writing, and the patentee, his assigns or legal representatives,
may in like manner grant and convey an exclusive right under the
patent, and where the conveyance precedes the granting of the
patent, it may be issued to the assignee, the assignment thereof
being first entered of record in the Patent Office. 16 Stat. 202,
203; Rev.Stat., secs. 4895, 4896.
Sufficient appears to show that the complainant claims to be the
lawful owner of the patented improvement, which consists of a new
mode of operating railroad brakes, and that he became such, as he
alleges, by virtue of an instrument of assignment, bearing date
July 13, 1854, from the assignee of the original inventors.
Prior to the granting of the patent, to-wit, on the first day of
April, 1852, the inventors conveyed and set over to the assignor of
the complainant all the right, title, and interest whatever which
they had, or by letters patent would be entitled to have and
possess, in the described invention, and the record shows
Page 98 U. S. 549
that the assignment was duly recorded in the Patent Office, as
required by law.
Such an assignment may be made before the patent is obtained,
and provision is made that the patent may be issued to the
assignee, provided the application is made and duly sworn to by the
inventor himself, and the assignment is duly recorded. When so
granted, the exclusive interest is vested as a legal estate in the
assignee, who thus becomes the lawful holder of the invention, and
the inventor himself is divested of the legal title. Curtis,
Patents (4th ed.), sec. 168; 16 Stat. 202.
By virtue of the assignment the legal title to the invention
vested in the assignee of the inventors, and the record also shows
that the patent, on the 6th of July, 1852, was duly issued in his
name, it appearing that the application for the same was duly sworn
to by the inventors, and that the assignment was duly recorded in
the Patent Office, as the act of Congress requires.
Even the respondent concedes that the legal title to the
invention was vested in the assignee, as the patentee named in the
patent, for the period of fourteen years, which is the term for
which the patent was granted. From the date of the assignment to
the close of the term for which the patent was granted, it is
conceded that the legal title to the invention became vested in the
assignee of the inventors, by virtue of the instrument of
assignment which they executed to the assignee before the patent
was issued. Such an instrument, though executed before the patent
is granted, transfers the legal title to the assignee.
10 How. 477; Rathbone v. Orr,
McLean 131; Rich v. Lippincott,
2 Fish. 1; Herbert v.
4 Mas. 15; Dixon v. Meyer,
4 Wash. 72.
Assume that the legal title to the invention was in the
assignee, and it requires no argument to prove that he could convey
the entire interest to a purchaser for a valuable consideration.
Well founded doubt upon that subject cannot arise, and the record
shows that the assignee of the inventors, on the 13th of July,
1854, sold, assigned, transferred, and conveyed to the complainant
all his right, title, interest, and claim whatsoever which he then
had or may have in and to said invention and patent, and any
extension thereof that may hereafter be
Page 98 U. S. 550
granted, with certain specified exceptions not material to be
noticed in this investigation. Before the term of the original
patent expired, due application was made for a renewal and
extension of the patent; and it is conceded that it was duly
extended and renewed by the commissioner for the further term of
seven years from and after the expiration of the first term.
Controversy arising between these parties, the complainant
instituted the present suit in the circuit court against the
respondent. When instituted, the bill of complaint contained many
matters which are wholly immaterial in the present controversy, and
consequently are omitted. Suffice it to say in this connection that
the complainant charges that the respondent has infringed his
exclusive right under the extended term of the patent, and prays
for process and for an account.
Service was made, and the respondent appeared and demurred to
the bill of complaint, showing for cause that the complainant has
not in and by his amended bill of complaint made any such title in
himself to the extended term of the patent therein set forth as
entitles him to any relief. Hearing was had and the court overruled
the demurrer and entered a decree in favor of the complainant, the
respondent electing to stand upon his demurrer. Prompt appeal was
taken by the respondent to this court, and he maintains the same
proposition that he did in the court below, to-wit, that the bill
of complaint shows no legal title to the extended term in the
When the patentee assigns the patent to a purchaser, the
assignee acquires only the exclusive right to make, use, and vend
the patented improvement during the term for which the patent was
granted, unless the instrument of assignment contains words showing
that the parties intended that the instrument should be more
comprehensive and include the extended term in case an extension
should be granted by the commissioner. During the term for which
the patent is granted, the assignee of all the right, title, and
interest of the patentee in the same may himself sell, assign, and
convey the patent for the residue of the term granted, or he may
continue to hold the same during that period, and may make, use,
and vend the patented improvement, but his title to the invention
terminates when the term of the patent expires; nor will his
Page 98 U. S. 551
grantee stand in any better condition, as the maxim nemo dat
qui non habet
applies to the assignee of the patentee.
Benjamin, Sales (2d ed.) 5; Peer v. Humphrey,
2 Ad. &
Assignees of the patent from the patentee can only sell and
convey what they acquire by virtue of the instrument of assignment,
and inasmuch as the presumption is that the grantor contracts to
sell and convey only what is secured by the patent, the proper
construction of the instrument limits the right conveyed to the
term expressed in the patent, unless the instrument contains words
to indicate a different intent. Holders of patents may not be the
inventors, nor is it true in every case that the patent is issued
to the inventor. On the other hand, the inventor is vested by law
with the inchoate right to the exclusive use of the invention to
every extent that the Patent Act accords, which he may perfect and
make absolute by proceeding in the manner which the law
Bona fide inventors' rights are never derivative, and they, even
before the patent is issued, have the exclusive inchoate right not
only to the original patent that may issue, but to any reissue,
renewal, or extension that may thereafter be granted under the
Patent Act. Authorities to support that proposition are numerous
and decisive, and it is equally clear that they may sell, assign,
or convey the invention, including the inchoate right to obtain the
patent, and to surrender and reissue it or to procure a renewal or
extension of the monopoly from the commissioner, if the instrument
of assignment contains apt words to show that such was the intent
of the grantor.
Such an inventor has no exclusive right to make, use, and vend
the improvement until he obtains a patent for the invention, and
that is created and secured by the patent; nor can the inventor
maintain any suit for infringing the same before the patent is
issued, but the inventor, says Mr. Chief Justice Taney, is vested
by law with an inchoate right to the exclusive use, which he may
perfect and make absolute in the manner which the law requires.
Gayler v. Wilder, supra.
Enough appears in that case to show that the invention had been
made and the specification prepared to obtain a patent before the
instrument of assignment was executed, and the question was whether
the instrument was sufficient to transfer
Page 98 U. S. 552
the inchoate right of the inventor to the assignee, it appearing
by the language of the instrument that it was intended to operate
upon the perfect legal title which the inventor then had a lawful
right to obtain, as well as upon the imperfect and inchoate
interest which he also possessed. Speaking to that point, the
learned Chief Justice said there would seem to be no sound reason
for defeating the intention of the parties by restraining the
operation of the assignment to the right to obtain the patent, and
compelling them to execute another transfer of the other inchoate
right, unless the act of Congress makes it necessary in order to
render the transfer complete, and the court held that no such
second assignment is required, as the matter to be assigned is the
monopoly or the right of property vested in the inventor, so that
when the party acquired an inchoate right to it, and the power to
make that right perfect and absolute at his pleasure, the whole
interest of the inventor, whether the instrument was executed
before or after the patent issued, passed to the assignee.
Two other reasons were given by the Chief Justice in support of
the construction of the assignment, which the court adopted in that
case, both of which are entitled to weight:
1. That no purpose of justice would be subserved by the opposite
rule, which would require the execution of a second instrument to
accomplish what the parties intended to do by the first.
2. That the construction was the same as had prevailed in such
cases under the prior patent acts. Herbert v. adams,
Views of a like character were expressed by Mr. Justice Curtis
at a later period, in a case of great importance. Clum v.
2 Curt.C.C. 520. Prior to obtaining the patent, the
inventor conveyed to the assignee one undivided fourth part of the
invention, and all his rights and property therein; and the patent
having subsequently been obtained and the term extended, the
question was whether the assignee held the same interest in the
extended term. Both parties were represented by able counsel, and
the court, upon the authority of Gayler v. Wilder, supra,
held that the extended term passed by the assignment as well as the
original term. Discussion, it seems, had taken place at the bar in
respect to the extent of the property
Page 98 U. S. 553
of the inventor in his invention before it is secured by a
patent. Preliminary to that subject, he adverted to the fact that
the instrument of assignment only conveyed one quarter part of the
inchoate right. But the inventor, remarked the judge, has not only
an inchoate right to obtain a patent securing to him the exclusive
right to his invention for the term of fourteen years, but also a
further inchoate right to have the term extended on the conditions
annexed by the law to the right.
Differences of opinion prior to that time existed in some
quarters whether the inchoate right to obtain an extension of the
term was the proper subject of purchase and sale; but the court in
that case answered the inquiry in the affirmative, and supported
his conclusions by the following satisfactory reasons:
1. That the inchoate right to obtain an extension of the patent
appertains to the invention as well as the inchoate right to obtain
the original patent.
2. That each is incomplete, and its completion depends upon the
compliance by the inventor with the statutory conditions and the
performance by public officers of certain acts prescribed by
3. Though there is an additional condition annexed to the right
to obtain an extension of the term beyond what is required to
obtain a patent, yet that does not change the nature of the right,
and it no more prevents it from being the subject of a contract of
sale than any other condition which is attached to it, and he held
that the inchoate right to obtain the extension passed by the
assignment as well as the inchoate right to obtain the original
Instruments of the kind have more than once been construed by
this Court, and always in the same way, where the instrument was
executed under existing laws. Railroad Company v.
10 Wall. 367; Nicolson
Pavement Co. v. Jenkins,
14 Wall. 452.
A deed of assignment, says Mr. Justice Swayne, by which a
patentee of an invention conveys all the right, title, and interest
which he has in the "said invention," as secured to him by letters
patent, and also all right, title, and interest which may be
secured to him from time to time, the same to be held by the
assignee for his own use and that of his legal representatives to
the full end of the term for which said letters patent are or
Page 98 U. S. 554
may be granted, carries the entire invention and all alterations
and improvements and all patents whatsoever, issued and extensions
alike, to the extent of the territory specified in the
Beyond doubt, the assignment in that case was made subsequent to
the issuing of the patent; but the case fully supports the
proposition that the operation of such an instrument is not limited
to the term specified in the patent, where the instrument contains
apt words to show that the parties intended that its operation
should be more comprehensive.
Decisive support to that view is also found in the second case.
An assignment of an invention secured by letters patent, says Mr.
Justice Davis, is a contract, and, like all other contracts, is to
be construed so as to carry out the intention of the parties to it;
and he adds, that it is well settled that the title of an inventor
to obtain an extension may be the subject of a contract of sale,
and when it is, the instrument by which the sale was effected is
the proper subject of construction, in order to determine whether
it secures to the purchaser any subsequent extension of the patent,
or merely the patent for the original term.
Conveyance in that case was made of all the title and interest
the patentee had in the reissued patent, to be enjoyed by the
grantee and his legal representatives to the full end of the term
for which the patent is or may be granted. Taking the whole
instrument together, said the court in that case, it is quite clear
that it was intended to secure to the grantee and his assigns the
right to use the invention in the locality specified as long as the
patentee and his legal representatives have the right to use it
anywhere else. Manifestly, say the court, something more was
intended to be assigned than the interest secured by the patent,
and the court decided that it included the renewal as well as the
residue of the original term.
Apt words are required, where the conveyance is of an existing
patent, to show that the conveyance includes more than the term
specified in the patent; but where the conveyance is of the
invention, whether before or after the patent is obtained, the rule
is otherwise, unless there is something in the instrument to
indicate a different intention, the rule being that a
Page 98 U. S. 555
conveyance of the described invention carries with it all its
incidents, and all the well considered authorities concur that the
inchoate right to obtain a renewal or extension of the patent is as
much an incident of the invention as the inchoate right to obtain
the original patent; and if so, it follows that both are included
in the instrument which conveys the described invention, without
limitation or qualification. Emmons v. Sladden,
354; Gayler v. Wilder, supra; Clum v. Brewer, supra; Carnan v.
2 Bro.C.C. 84.
Viewed in the light of these suggestions, the Court is of
opinion that the entire interest in the invention passed from the
inventors to the assignor of the complainant by the instrument of
assignment which they executed to him before the patent was
granted, and that the patent was properly issued in the name of
their assignee. They, the inventors, do not controvert the
exclusive right of the complainant, nor does the respondent deny
that the terms of the assignment from the assignee of the inventors
to the complainant are amply sufficient to convey to him all that
he claims, if his assignor at the time held the title to obtain the
extended term; and the Court being of opinion that the assignor of
the complainant did hold that right, it follows that there is no
error in the record.