of a patentable invention alone reside. No one, therefore, can be permitted to disclaim, unless he or the alleged inventor from whom he derives his title has performed an inventive act, resulting in some material and substantial part of the thing patented which is so far separable from the excess that the patent can be valid for it, and protect it, after the excess has been disclaimed.

§ 646. Excessive Claim not Amendable by Disclaimer after Unreasonable Delay.

An excessive Claim can be amended by disclaimer only when the amendment is attempted without unreasonable delay. The same principle which forbids a patentee to assert a right to more than he has actually invented compels him to disavow the right as soon as he discovers that it has been unjustly claimed. Unreasonable delay in disclaiming is thus tantamount to an original fraudulent Claim, and through it the patentee loses the privilege of making the amendment by which alone his patent could be saved. The question of unreasonable delay is a question for the court, upon the facts as found either by its own investigation or the verdict of a jury. Delay begins whenever the patentee becomes aware that he has claimed more than he has invented or described. In cases where the excess is not apparent at once upon the inspection of the patent by the patentee, the allowance of his

§ 646. 1 That "unreasonable delay" avoids the good effect of a disclaimer, see Tuck v. Bramhill (1868), 6 Blatch. 95; 3 Fisher, 400; Singer v. Walmsley (1860), 1 Fisher, 558; Seymour v. McCormick (1856), 19 How. 96; Brooks v. Jenkins (1844), 3 McLean, 432.

That a delay in filing a disclaimer does not prejudice the patentee unless it is unreasonable, see Hotchkiss v. Oliver (1848), 5 Denio (N. Y.), 314.

That no disclaimer can be filed after the patent has expired, see Yale Lock Mfg. Co. v. Sargent (1886), 117 U. S. 536; 35 O. G. 497; Vacuum Oil Co. v. Buffalo Lubricating Oil Co. (1885), 23 Fed. Rep. 891.

2 In Singer v. Walmsley (1860), 1 Fisher, 558, Giles, J.: (575) “What is 'unreasonable delay' is a question to be settled by the court and not for the jury. . . . The court will find that the time, in reference to the question of delay, commences when the knowledge was brought home to the party that he was not the first inventor, or when it is declared by a court, of competent juris. diction to settle the question, that he was not the first inventor; then it is that the time commences to run, and not until then."

See also Seymour v. McCormick (1856), 19 How. 96; Brooks v. Jenkins (1844), 3 McLean, 432.

Claim by the Patent Office raises such a presumption in its favor that he may rely on its validity until a court of competent jurisdiction decides that it is broader than his real invention.3

§ 647. Disclaimer, by Whom Made.

Where an excessive Claim can be cured by disclaimer, the disclaimer must be filed by a party owning an interest in the patent and whose interest is distinct from that of his coowners. The original patentee cannot disclaim after he has parted with his entire title to the patent.2 An owner of an undivided interest cannot disclaim, and thus change the form of the patent, without the co-operation of the other owners of the same interest in the patent. But an owner either of the entire patent, or of the entire interest within a specified territory, may file a disclaimer; and when the disclaimant is a territorial owner its effect upon the patent will be commen

In O'Reilly v. Morse (1853), 15 How. 62, Taney, C. J.: (121) "It appears that no disclaimer has yet been entered at the Patent Office. But the delay in entering it is not unreasonable. For the objectionable Claim was sanctioned by the head of the Office; it has been held to be valid by a circuit court, and differences of opinion in relation to it are found to exist among the justices of this court. Under such circumstances the patentee had a right to insist upon it, and not disclaim it until the highest court to which it could be carried had pronounced its judgment." See also Seymour v. McCormick (1856), 19 How. 96.

That the allowance of Claims by the Patent Office is such evidence of their validity that the patentee may rely upon it until the courts have decided to the contrary, see Yale Lock Mfg. Co. v. Sargent (1886), 117 U. S. 536; 35 O. G. 497; Stutz v. Armstrong (1884), 28 O. G. 367; 20 Fed. Rep. 843; Burdett v. Estey (1878), 15 Blatch. 349; 15 0. G. 877.

That delay in disclaiming cannot exist until the need of a disclaimer is made known, see Kittle v. Hall (1887), 30 Fed. Rep. 239.

That a disclaimer may be filed after a patent has been adjudged invalid, see Morgan v. Seaward (1838), Carp. P. C. 104; In re Derosne's Patent (1835), 1 Carp. P. C. 698.

§ 647. That a disclaimer must be made by one who owns an entire right within a given territory, see Myers v. Frame (1871), 4 Fisher, 493; 8 Blatch. 446.

2 That a disclaimer by a patentee is not valid unless he is still the owner of the patent, see Myers v. Frame (1871), 4 Fisher, 493; 8 Blatch. 446.

That under the English statute a disclaimer may be filed by a patentee who has parted with his interest, see Spilsbury v. Clough (1842), 1 Web. P. C. 255.

That a disclaimer by an attorney does not necessarily bind a patentee, see Mann v. Bayliss (1876), 10 O. G. 789.

surate only with his interest; and the patent as amended will thereafter limit and define his rights, while other parties hold under the patent in its original form.3 Thus the same patent may be operative, in terms at least, to different extents in different sections of the United States, and may be valid as to diligent disclaimants, though void as to other owners who have unreasonably neglected to disclaim.

§ 648. Disclaimer, how Made.

A disclaimer must be made in writing, must be signed by the disclaimant and attested by one or more witnesses, and must be recorded in the Patent Office. It must state the exact interest of the disclaimant in the patent, and distinctly set out the excess which is to be disclaimed, averring that it was included in the patent through inadvertence, accident, or mistake. Upon the receipt and recording of this disclaimer, it is considered as part of the original specification, to the extent of the interest possessed by the disclaimant and by those deriving title from him after the disclaimer is recorded.2

8 In Potter v. Holland (1858), 1 Fisher, 327, Ingersoll, J.: (339) “The owner of a sectional interest, however, can make a disclaimer for his sectional interest, which is to be taken as a part of the original specification, for the sec tion owned by him, and no greater ex

tent. After such disclaimer a different claim of right is secured to the disclaimant, the owner of a sectional interest, from what is purported to be secured to the patentee, the owner of the remaining interest; different claims of right in the same invention are se cured to different sectional owners; there are two specifications for the same invention, one, making one claim of right to an invention for one section of country, and the other making another and different claim of right to the same invention, for another section of country. In effect it makes two patents out of one, one securing a claim of right to one person, and the other securing a

different claim of right to another person. This is expressly authorized by the Patent Law." 4 Blatch. 206 (217).

That the word 'claimant" in Sec. 4917 Rev. Stat. means disclaimant, see Union Metallic Cartridge Co. v. United States Cartridge Co. (1884), 112 U. S. 624; 30 O. G. 771.

§ 648. That a disclaimer, under Sec. 7, act of 1837, must state the interest of the disclaimant, or it will be invalid, see Foote v. Silsby (1849), 1 Blatch. 445; Brooks v. Jenkins (1844), 3 McLean, 432.

2 That a disclaimer becomes part of the specification and is considered in construing the patent, see Dunbar v. Myers (1877), 94 U. S. 187; 11 0. G. 35.

That a disclaimer may relate to one figure only in a drawing, see Brush v. Condit (1884), 28 O. G. 451; 22 Blatch. 246; 20 Fed. Rep. 826.

$649. Disclaimer not a Method of Amending a Defective Description.

From the nature of a disclaimer, and of the defect it is intended to remedy, it is evident that it cannot be employed for the alteration or reformation of the Description, but only for the elimination of superfluous matter from the Claims.1 If the Description requires amendment in order to give effect to a Claim, or if the Claim itself demands restatement to avoid obscurity, or if new Claims are necessary to protect the actual invention, these objects must be sought by a re-issue, not by

§ 649.1 In Hailes v. Albany Stove Co. (1887), 123 U. S. 582, Bradley, J.: (587) "A disclaimer is usually and properly employed for the surrender of a separate Claim in a patent, or some other distinct and separable matter, which can be exscinded without mutilating or changing what is left standing. Perhaps it may be used to limit a Claim to a particular class of objects, or even to change the form of a Claim which is too broad in its terins; but certainly it cannot be used to change the character of the invention. And if it requires an amended specification or supplemental Description to make an altered Claim intelligible or relevant, while it may possibly present a case for a surrender and re-issue, it is clearly not adapted to a disclaimer. A man cannot by merely filing a paper drawn up by his solicitor make to himself a new patent, or one for a different invention from that which he has described in his specification." 42 O. G. 95 (97).

virtue of the patent or assignment.' A disclaimer can be made only when something has been claimed of which the patentee was not the original or first inventor, and when it is intended to limit a Claim in respect to the thing so not originally or first invented. It is true that, in so disclaiming or limiting a Claim, descriptive matter on which the disclaimed Claim is based may, as incidental, be erased, in aid of, or as ancillary to, the disclaimer. But the statute expressly limits a disclaimer to a rejection of something before claimed as new or as invented, when it was not new or invented, and which the patentee or his assignee no longer chooses to claim or hold. It is true that this same end may be reached by a re-issue, when the patentee has claimed as his own invention more than he had a right to claim as new; but if a Claim is not to be rejected or limited, but there is merely a defective or insufficient specification,' - that is, Description, as distinguished from a Claim, the only mode of correcting it was and is by a reissue." 30 O. G. 771 (775).

That a disclaimer cannot be used to

make a patent cover what is not described or claimed as part of the invention, see White v. Gleason Mfg. Co. (1883), 24 O. G. 205; 21 Blatch. 364; 17 Fed. Rep. 159; Foxwell v. Bostock (1864), 4 De G. J. & S. 298.

a disclaimer. But where excessive Claims are to be remedied by a disclaimer, such parts of the Description as serve no other purpose than to support the excess disclaimed may also be withdrawn by the disclaimer, and the distinction between the actual invention and the excess be thus more clearly indicated. In the same manner objectionable phrases in the