INTERFERENCES.

When each of two or more persons claims to be the first inventor of the same thing, an "interference" is declared between them, and a trial is had before an officer called the examiner of interferences. Nor does the fact that one of the parties has already obtained a patent prevent such an interference; for, although the commissioner has no power to cancel a patent already issued, he may, if he finds that another person was the prior inventor, give him also a patent, and thus place them on an equal footing before the courts and the public. If an applicant for a re-issue embraces in his amended specification any new or additional description of his invention, or enlarges his claim, or makes a new one, and thereby includes therein anything which has been claimed in any patent granted subsequent to the date of his original application, as the invention of another person, an interference will be declared between the application and any unexpired patent, or pending applica tion, in which the same thing is claimed; but not where such pending application for re-issue claims only what was granted in the original patent.

When an application is found to conflict with a caveat, the caveator is allowed a period of three months within which to present an application, when an interference may be declared. In cases of interference, patentees have the same remedies by appeal as applicants in pending applications.

Each party to the interference will be required to file a concise statement under oath showing the date of his original conception of the invention, of its illustration by drawing or model, of its disclosure to others, of its completion, and of the extent of its use.

The parties will be strictly held in their proof to the dates set up in their statements. These statements must be sent under seal, and the name of the party, title of the case, and nature of the invention endorsed on the envelope.

Neither party is allowed to see the statement of the other until both have been filed.

An applicant involved in an interference may, before the date fixed for filing his statement, disclaim over his own signature attested by two witnesses, the invention of the particular

matter in issue, and upon such disclaimer and the cancellation of any claims involving such interfering matter, judgment shall be rendered against him and the disclaimer shall be embodied in and form part of his specification.

In cases of interference, the party who first made oath to the invention will be deemed the first inventor in the absence of all proof to the contrary. A time will be assigned in which the other party shall complete his direct testimony, and a further time in which the adverse party shall complete the testimony on his side; and a still further time in which the first party shall close his rebutting testimony, but shall take no other. If there are more than two parties, the times for taking testimony shall be so arranged that each shall have a like opportunity in his turn, each being held to go forward and prove his case against those who made oath to their applications before him. If either party wishes the time for taking his testimony, or for the hearing, postponed, he must make application for such postponement, and must show sufficient reason for it by affidavit filed before the time previously appointed has elapsed, if practicable; and must also furnish his opponent with copies of his affidavits, and with seasonable notice of the time of hearing his application.

In contested cases, whether of interference or of extension, parties may have access to the testimony on file, prior to the hearing, in presence of the officer in charge; or when practicable, copies may be obtained by them at the usual charges.

RE-ISSUES.

A re-issue is granted to the original patentee, his heirs, or the assignees of the entire interest, when, by reason of an insufficient or defective specification, the original patent is inoperative or invalid, provided the error has arisen from inadvertence, accident, or mistake, without any fraudulent or deceptive intention.

Unless applied for immediately after the issue of the original patent, a re-issue will not be allowed for the purpose of expanding or enlarging the claims of the original, even though the invention, as thus claimed, was described or shown in the origi

nal specification and drawings, and might properly have been embraced in the original patent. Two years has been indicated. as the extreme limit within which re-issues for this purpose will be allowed.

The courts have recently construed re-issued patents very strictly in this respect, and it is therefore very important that the inventor should carefully examine his patent as soon as possible after its issue to ascertain that it embraces everything to which he is justly entitled.

Re-issued patents expire at the same time that the original patent would have done. For this reason, applications for re-issue will be acted upon immediately after they are completed.

A patentee may, at his option, have in his re-issue a sepa rate patent for each distinct part of the invention comprehended in his original application, by paying the required fee in each case, and complying with the other requirements of the law, as in original applications. Each division of a re-issue constitutes the subject of a separate specification descriptive of the part or parts of the invention claimed in such division; and the drawing may represent only such part or parts. One or more divisions of a re-issue may be granted, though other divisions shall have been postponed or rejected. In all cases of applications for re-issues, the original claim is subject to re-examination, and may be revised and restricted in the same manner as in original applications.

The petition for re-issue must be signed and sworn to by the inventor if he be living, and must be accompanied with a certified copy of the abstract of title, giving the names of all assignees owning any undivided interest in the patent; and with the written assent of such assignees.

The applicant must also file with his petition a statement setting forth particularly the defects or insufficiencies in the specification which render the patent inoperative or invalid, and how such errors arose, and in cases where more was claimed and allowed than he was entitled to claim as new, such part or parts must be distinctly pointed out. At the same time the original patent must be surrendered, or if that be lost an affidavit to

that effect and a certified copy of the patent. New drawings must also be furnished as in the case of an original application.

(248a.)

Form of Petition for Re-issue.

TO THE COMMISSIONER OF PATENTS:

Your petitioner, A. B., a citizen of the United States residing at L., in the County of M. and State of N. (or subject of, etc.), prays that he may be allowed to surrender the letters patent for an improvement in granted to him 188, whereof he is now sole owner (or whereof C. D., on whose behalf and with whose assent this application is made, is now sole owner by assignment), and that letters patent may be issued to him for the said C. D.) for the same invention upon the annexed amended specification. With this petition is filed an abstract of title, duly certified, as required in such cases. A. B.

Assent of Assignee to Re-issue.

The undersigned, assignee of the entire (or undivided) interest in the abovementioned letters patent, hereby assents to the accompanying application.

(249.)

C. D.

Form of Oath to be Appended to Applications for.

STATE OF

Re-issue.

SS.

COUNTY OF

A. B., the above-named petitioner, being duly sworn, deposes and says that he verily believes that his aforesaid letters patent are inoperative (or invalid or both) by reason of a defective (or insufficient) specification (or both, or by reason of the patentee claiming as his own invention or discovery more than he had a right to claim as new) and that the error arose by inadvertence (accident or mistake) without any fraudulent or deceptive intent; that he is the sole owner of said letters patent (or that E. F. is the sole owner of said letters patent, and that this application is made on the behalf and with the consent of the said E. F.) and that he verily believes himself to be the first and original inventor of the improvement set forth and claimed in this amended specification, and does not believe that the same was ever before known or used.

A. B.

Applications for re-issues will not be kept secret; and in. formation respecting the same will be furnished upon inquiry, as well as copies of the proposed claims for publication.

DISCLAIMERS.

Where, by inadvertence, accident, or mistake, the original patent is too broad, a disclaimer may be filed either by the original patentee or by any assignee of the patent or of any sectional interest therein.

The following is a sufficient form for a disclaimer:

(250.)

Form for a Disclaimer.

TO THE COMMISSIONER OF PATENTS:

Your petitioner, A. B., a citizen of the United States, residing at L. in the County of M. and State of N. (or a subject of &c.) represents that in the matter of a certain improvement in for which letters patent of

the United States, No. were granted to him (or to C. D.) on the day of he is (here state the exact interest of the disclaimant; it assignee, set out book and page where assignment is recorded) and that he has reason to believe that through inadvertence (accident or mistake) the specification and claim of said letters patent are too broad, including that of which said patentee was not the first inventor.

Your petitioner therefore, hereby enters his disclaimer to that part of the claim in said specification which is in the following words, to wit: Witness:

A. B.

E. F.

EXTENSIONS.

No patents now in force can be extended except by a special act of Congress.

Such extensions are rarely granted, and therefore the rules of the office in reference to them are of too limited application to be inserted here.

DESIGNS.

Patents for Designs are provided for by section 4929 of the Revised Statutes of the United States, as follows:

"Any person, who by his own industry, genius, efforts, and expense, has invented or produced any new and original design for a manufacture, bust, statue, alto-relievo, or bas-relief; any