present time. The fifty-third section of the act of 1870, c. 230, which was the law on this subject when the re-issue in the present case was granted, is in the following words: Whenever any patent is inoperative or invalid by reason of a defective or insufficient specification, or by reason of the patentee claiming as his own invention or discovery more than he had a right to claim as new, if the error has arisen by inadvertence, accident, or mistake, and without any fraudulent or deceptive intention, the Commissioner shall, on the surrender of such patent, and the payment of the duty required by law, cause a new patent for the same invention, and in accordance with the corrected specification, to be issued to the paten tee.' It will be observed that while the law authorizes a re-issue when the patentee has claimed too much, so as to enable him to contract his Claim, it does not, in terms, authorize a re-issue to enable him to expand his Claim. The great object of the law of re-issues seems to have been to enable a patentee to make the description of his invention more clear, plain, and specific, so as to comply with the requirements of the law in that behalf, which were very comprehensive and exacting. The third section of the act of 1793, c. 11, required an applicant for a patent 'to deliver a written description of his invention, and of the manner of using, or process of compounding the same, in such full, clear, and exact terms as to distinguish the same from all other things before known, and to enable any person skilled in the art or science of which it is a branch, or with which it is most nearly connected, to make, compound, and use the same. And in the case of any machine, he shall fully explain the principle, and the several modes in which

he has contemplated the application of that principle or character, by which it may be distinguished from other inventions; and he shall accompany the whole with drawings and written references, where the nature of the case admits of drawings.' This careful and elaborate requirement was substantially repeated in the sixth section of the act of 1836, with this addition: And shall particularly specify and point out the part, improvement, or combination which he claims as his own invention or dis covery.' Although it had been cus tomary to append a Claim to most specifications, this was the first statu tory requirement on the subject. It was introduced into the law several years subsequently to the creation of re-issues; and it was in the thirteenth section of this act of 1836 that provision was made for a re-issue to correct a Claim which was too broad in the original. Now, in view of the fact that a re-issue was authorized for the correction of mistakes in the specification before a formal Claim was required to be made, and of the further fact that when such formal Claim was required express power was given to grant a re-issue for the purpose of making a Claim more narrow than it was in the original, without any mention of a re-issue for the purpose of making a Claim broader than it was in the original, it is natural to conclude that the re-issue of a patent for the latter purpose was not in the mind of Congress when it passed the laws in question. It was probably supposed that the patentee would never err in claiming too little. Those who have any experience in business at the Patent Office know the fact that the constant struggle between the Office and applicants for patents has reference to the Claim. The patentee seeks the

broadest Claim he can get. The Office, in behalf of the public, is obliged to resist this constant pressure. At all events, we think it clear that it was not the special purpose of the legislation on this subject to authorize the surrender of patents for the purpose of re-issuing them with broader and more comprehensive Claims, although, under the general terms of the law, such a re-issue may be made where it clearly appears that an actual mistake has inadvertently been made. But by a curious misapplication of the law it has come to be principally resorted to for the purpose of enlarging and expanding patent Claims. And the evils which have grown from the practice have assumed large proportions. Patents have been so expanded and idealized, years after their first issue, that hundreds and thousands of mechanics and manufacturers, who had just reason to suppose that the field of action was open, have been obliged to discontinue their employments, or to pay an enormous tax for continuing them. Now, while, as before stated, we do not deny that a Claim may be enlarged in a re-issued patent, we are of opinion that this can only be done when an actual mistake has occurred, not from a mere error of judgment (for that may be rectified by appeal), but a real bona fide mistake, inadvertently committed, such as a court of chancery, in cases within its ordinary jurisdiction, would correct. Re-issues for the enlargement of Claims should be the exception and not the rule; and when, if a Claim is too narrow, that is, if it does not contain all that the patentee is entitled to, -the defect is apparent on the face of the patent and can be discovered as soon as that document is taken out of its envelope and opened, there can be no valid

excuse for delay in asking to have it corrected. Every independent inventor, every mechanic, every citizen, is affected by such delay, and by the issue of a new patent with a broader and more comprehensive Claim. The granting of a re-issue for such a purpose after an unreasonable delay is clearly an abuse of the power to grant re-issues, and may justly be declared illegal and void. It will not do for the patentee to wait until other inventors have produced new forms of improvement, and then, with the new light thus acquired, under pretence of inadvertence and mistake, apply for such an enlargement of his Claim as to make it embrace these new forms. Such a process of expansion, carried on indefinitely, without regard to lapse of time, would operate most unjustly against the public, and is totally unauthorized by the law. In such a case, even he who has rights and sleeps upon them justly loses them." 21 O. G. 201 (202).

The statements contained in the foregoing extract are responsible for the widely-spread impression that the case of Miller v. Brass Co. introduced radi cal changes into the law of re-issues. But the case itself, taken as a whole, warrants no such impression. In view of the facts apparent on the record, the judgment of the court was eminently just. The conclusions of the learned judge who delivered the opinion, — that a re-issue is proper only where the defect to be amended was "a bona fide mistake inadvertently committed;" that an unreasonable delay in applying for a re-issue indicates that the allegation of original "inadvertence or mistake is a mere pretence;" that when the defect is evident on an inspection of the patent, as is usually the case where it consists in an undue restriction of the

Claim, any avoidable delay is unreasonable, - are supported not only by sound reason and the general analogies of the law, but by an almost unbroken current of judicial decisions. In reaching these conclusions, however, the court pursues the novel line of argument set forth in the passage above quoted, and seems to find the ground for its refusal to recognize the re-issued patent in the equitable doctrine that laches may for feit an existing right, rather than in the rule of Patent Law that laches in reissuing is inconsistent with the original existence of the right itself. An analysis of this argument results in the following propositions :

(1) That prior to the act of 1836 the law did not require a formal Claim of the invention to be inserted in the specification.

(2) That prior to this act, therefore, the errors contemplated by the law governing re-issues, and curable by that mode of amendment, were errors in the Description, not the Claim.

(3) That when the Claim was made an essential part of the specification the law of re-issues was enlarged to embrace errors arising in the Claim.

(4) That as this extension of the law of re-issues expressly related only to errors consisting in an excess of Claim, it impliedly excluded from the operation of that law all errors which result from an undue restriction of the Claim.

(5) That, being thus excluded, the correction of an unduly restricted Claim is not within the special purpose of the legislation concerning re-issues; and, though permitted, must find its warrant in the general terms of the law and in the principles of equity.

a court of chancery, if the case were within its jurisdiction, would order the amendment; and though otherwise proper, may be refused whenever the patentee has slept upon his rights or when the interests of others would be unjustly prejudiced by the re-issue.

But

In the case under consideration the final judgment must have been the same whether attained by this mode of reasoning or by that which, treating the correction of restricted Claims as within the ordinary amending powers conferred by the statutes, regards unreasonable delay, etc., as bearing only upon the ques tion of original inadvertence or mistake. The same would probably be true in nearly every case where the lawfulness of a re-issue was to be determined by the Patent Office or the courts. since the propositions above enumerated in effect transfer this class of re-issues from the statutory jurisdiction of the Patent Office to the chancery jurisdic tion of the courts, and render their validity dependent not merely on the conditions named in the statute but on the equities arising after the issue of the patent, thus opening a wide and deep gulf of separation between these reissues and all others; and since these several propositions, taken as the statement of special doctrines of Patent Law, have led to decisions in many later cases which are evidently erroneous in principle; it is important that so far as they are incorrect they should be, if possible, refuted. The fundamental error seems to reside in the deduction drawn in the second proposition from the fact stated in the first. It is true that before the act of 1836 the law did not require a formal Claim to be inserted in the specification; but it does not follow from this that under the provisions of preceding statutes no claim

(6) That the correction of restricted Claims is, therefore, lawful only where

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