Mr. Chief Justice Fuller,
after stating the case, delivered the opinion of the court.
The Court of Appeals for the District of Columbia adjudged that Northall was entitled to the patent. By section 8 of the act establishing that court, 27 Stat. 434, c. 74, it is provided that any final judgment or decree thereof may be revised by this court on appeal or error in cases wherein the validity of a statute of the United States is drawn in question. The validity of the act of Congress allowing an appeal to the Court of Appeals in interference cases was necessarily determined when that court went to judgment, yet no attempt was made to bring the case directly to this court, but the relator applied to the District Supreme Court to compel the Commissioner to issue the patent in disregard of the judgment of the Court of Appeals to the contrary, and, the application having been denied, the Court of Appeals was called on to readjudicate the question of its own jurisdiction.
The ground of this unusual proceeding, by which the lower court was requested to compel action to be taken in defiance of the court above, and the latter court was called on . to rejudge its own1 judgment, was that the decree of the Court of Appeals was utterly void because of the unconstitutionality of the statute by which it was empowered to exercise jurisdiction.
Nothing is better settled than that the writ of mandamus will not ordinarily be granted if there is another legal remedy, nor unless the duty sought to be enforced is clear and indisputable ; and we think that, under the circumstances, the remedy by appeal existed; and that it is not to be conceded that. it was the duty of the Commissioner to disobey the decree because in his judgment the statute authorizing it was unconstitutional, or that it would have been consistent with the orderly and decorous administration of justice for the District Supreme Court to hold that the Court of Appeals was absolutely destitute of the jurisdiction which it had determined it possessed. Even if we were of opinion that the act of Congress was not in harmony with the Constitution, every presumption was in favor of its validity, and we cannot assent to the proposition that it would have been competent for the Commissioner to treat the original decree as absolutely void, and without force and effect as to all persons and for all purposes.
But as, in our opinion, the Court of Appeals had jurisdiction, we prefer to affirm the judgment on that ground.
The contention is that Congress had no power to authorize the Court of Appeals to review the action of the Commissioner in an interference case, on the theory that the Commissioner is an executive officer; that his action in determining which of two claimants is entitled to a patent is purely executive ; and that, therefore, such action cannot be subjected to the revision of a judicial tribunal.
Doubtless, as was said in Murray v. Hoboken Land & Improvement Co., 18 How. 272, 284, Congress cannot bring under the judicial power a matter which, from its nature, is not a subject for judicial determination, but at the same time, as Mr. Justice Curtis, delivering the opinion of the court, further observed, " there are matters involving public rights, which may be presented in such form that the judicial power is capable of acting on them, and which are susceptible of judicial determination,- but which Congress may or may not bring within the cognizance of the courts of the United States, as it may deem proper." The instances in which this has been done are numerous, and many of them are referred to in Fong Yue Ting v. United States, 149 U. S. 698, 714, 715, 728.
Since, under the Constitution, Congress has power "to promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries," and to make all laws which shall be necessary and proper for carrying that expressed power into execution, it follows that Congress may provide such instrumentalities in respect of securing to inventors the exclusive right to their discoveries as in its judgment will be best calculated to effect that object.
And by reference to the legislation on the subject, a comprehensive sketch of which was given by Mr. Justice Matthews in Butterworth v. Hoe, 112 U. S. 50, it will be seen that from 1790 Congress has selected such instrumentalities, varying them from time to time, and, since 1870, has asserted the power to avail itself of the courts of the District of Columbia in that connection.
The act of April 10, 1790, c. 7, 1 Stat. 109, authorized the issue of patents by the Secretary of State, the Secretary for the Department of War, and the Attorney General, or any two of them, " if they shall deem the invention or discovery sufficiently useful and important," and this was followed by the act of February 21, 1793, c. 11, 1 Stat. 318, authorizing them to be issued by the Secretary of State, upon the certificate of the Attorney General that they were conformable to the act. The ninth section of the statute provided for the case of interfering applications, which were to be submitted to the decision of three arbitrators, chosen one by each of the parties and the third appointed by the Secretary of State, whose decision or award, or that of two of them, should be final as respected the granting of the patent.
Then came the act of July 4, 1836, c. 357, 5 Stat. 117, ere ating in the Department of State the Patent Office, "the chief officer of which shall be called the Commissioner of Patents," and " whose duty it shall, be, under the direction of the Secretary of State, to superintend, execute and perform, all such acts and things touching and respecting the granting and issuing of patents for new and useful discoveries, inventions and improvements, as are herein provided for, or shall hereafter be, by law, directed to be done and performed." . . . By that act it was declared, to be the duty of the Commissioner to issue a patent if he " shall deem it to be sufficiently useful and important; " and, in case of his refusal, the applicant was (sec. 7) secured an appeal from his decision to a board of examiners, to be composed of three disinterested persons, appointed for that purpose by the Secretary of State, one o'f whom, at least, to be selected, if practicable and convenient, for his knowledge and skill in the particular art, manufacture or branch of science to which the alleged invention appertained. The decision of this board being certified to the Commissioner, it was declared that " he shall be governed thereby in the further proceedings to be had on such application." A like proceeding, by way of appeal, was provided in cases of interference. By section 16 of the act a remedy by bill in equity, still existing in sections 4915, 4918, Devised Statutes, was given as between interfering patents or whenever an application had been refused on an adverse decision of a board of examiners. By section 11 of the act of March 3, 1839, c. 88, 5 Stat. 353, 354, as modified by the act of August 30, 1852, c. 107, 10 Stat. 75, it was provided that in all cases where an appeal was thus allowed by law from the decision of the Commissioner of Patents to a board of examiners, the party, instead thereof, should have a right to appeal to the chief judge or to either of the assistant judges of the Circuit Court of the District of Columbia; and by section 10 the provisions of section 16 of the act of 1836 were extended to all cases where patents were refused for any reason whatever, either by the Commissioner or by the chief justice of the District of Columbia upon appeals from the decision of the Commissioner, as well as where the same shall have been refused on account of or by reason of interference with a previously existing patent.
By the act of March 3, 1849, c. 108, 9 Stat. 395, the Patent Office was transferred to the Department of the Interior. The act of March 2, 1861, c. 88, 12 Stat. 246, created the office of examiners in 'chief, "for the purpose of securing greater uniformity of action in the grant and refusal of letters patent," " to be composed of persons of competent legal knowledge and scientific ability, whose duty it shall be, on the written petition of the applicant for that purpose being filed, to revise and determine upon the validity of decisions made by examiners when adverse to the grant of letters patent ; and also to revise and determine in like manner upon the validity of the decisions of examiners in interference cases, and when required by the Commissioner in applications for the extension of patents, and to perform such other duties as may be assigned to them by the Commissioner; that from their decisions appeals may be taken to the Commissioner of Patents in person, upon payment of the fee hereinafter prescribed ; that the said examiners in chief shall be governed in their action by the rules to be prescribed by the Commissioner of Patents."
The act of July 8, 1870, c. 230,16 Stat. 198, revised, consolidated and amended the statutes then in force on the subject, and by section 48, an appeal to the Supreme Court of the District of Columbia sitting in banc was provided for, whose decision was to govern the further proceedings in the case (sec. 50); and the provisions of the act material to the present inquiry were carried in substance into the existing revision.
By the act of February 9, 1893, c. 74, 27 Stat. 434, the determination of appeals from the Commissioner of Patents, which was formerly vested in the General Term of the Supreme Court of the District, was vested in the Court of Appeals, and, in addition, it was provided that "any party aggrieved by a decision of the Commissioner of Patents in any interference case may appeal therefrom to said Court of Appeals."
As one of the instrumentalities designated by Congress in execution of the power granted, the office of Commissioner of Patents was created, and though he is an executive officer, generally speaking, matters in the disposal of which he exercises functions judicial in their nature may properly be brought within the cognizance of the courts.
Now, in deciding whether a patent shall issue or not, the Commissioner acts on evidence, finds the facts, applies the law and decides questions affecting not only public but private interests ; and so as to reissue, or extension or on interference between contesting claimants; and in all this he exercises judicial functions.
In Butterworth v. Hoe, supra, Mr. Justice Matthews, referring to the constitutional provision, well said :
" The legislation based on this provision regards the right of property in the inventor as the medium of the public advantage derived from his invention; so that in every grant of the limited monopoly two interests are involved, that of the public, who are the grantors, and that of the patentee. There are thus two parties to every application for a patent, and more, when, as in case of interfering claims or patents, other private interests compete for preference. The questions of fact arising in this field find their answers in every department of physical science, in every branch of mechanical art; the questions of law, necessary to be applied in the settlement of this class of public and private rights, have founded a special branch of technical jurisprudence. The investigation of every claim presented involves the adjudication of disputed questions of fact, upon scientific or legal principles, and is, therefore, essentially judicial in its character, and requires the intelligent judgment of a trained body of skilled officials, expert in the various branches of science and art, learned in the history of invention, and proceeding by fixed rules to S3?stematic conclusions."
That case is directly in point and the ratio decidendi strictly applicable to that before us. The case was a suit in mandamus brought by the claimant of a patent in whose favor the Commissioner had found in an interference case, to compel the Commissioner to issue the patent to him. The Commissioner hatl refused to do this on the ground that the defeated party had appealed to the Secretary of the Interior, who had reversed the Commissioner's action, and found in appellant's favor. This court held that while the Commissioner of Patents was an executive officer and subject in administrative or executive matters to the supervision of the head of the department, yet that his action in deciding patent cases was essentially judicial in its nature and not subject to review by the executive head, an appeal to the courts having been provided for. And among other things it was further said:
" It is evident that the appeal thus given to the. Supreme Court of the District of Columbia from the decision of the Commissioner, is not the exercise of ordinary jurisdiction at law or in equity on the part of that court, but is one in the statutory proceeding under the patent laws whereby that tribunal is interposed in aid of the Patent Office, though not subject to it. Its adjudication, though not binding upon any who choose by litigation in courts of general jurisdiction to question the validity of any patent thus awarded, is, nevertheless, conclusive upon the Patent Office itself, for, as the statute declares, Pev. Stat. §4914, it 'shall govern the further proceedings in the case.' The Commissioner cannot question it. He is bound to record and obey it. His failure or refusal to execute it by appropriate action would undoubtedly be corrected and supplied by suitable judicial process. The decree of the court is the final adjudication upon the question of right; everything after that dependent upon it is merely in execution of it; it is no longer matter of discretion, but has become imperative and enforceable. It binds the whole Department, the Secretary as well as the Commissioner, for it has settled the question of title, so that a demand for the signatures necessary to authenticate the formal instrument and evidence of grant may be enforced. It binds the Secretary by acting directly upon the Commissioner, for it makes the action of the latter final by requiring it to conform to the decree.
" Congress has thus provided four tribunals for hearing applications for patents, with three successive appeals, in which the Secretary of the Interior is not included, giving jurisdiction in appeals from the Commissioner to a judicial body, independent of the Department, as though he were the highest authority on the subject within it. And to say that under the name of direction and superintendence, the Secretary may annul the decision of the Supreme Court of the District, sitting on appeal from the Commissioner, by directing the latter to disregard it, is to construe a statute so as to make one part repeal another, when it is evident both were intended to coexist without conflict."
"No reason can be assigned for allowing an appeal from the Commissioner to the Secretary in cases in which he is by law required to exercise his judgment on disputed questions of law and fact, and in vThich no appeal is allowed to the courts that would not equally extend it to those in which such appeals are provided, for all are equally embraced in the general authority of direction and superintendence. That includes all or does not extend to any.' The true conclusion, therefore, is, that in matters of this description, in which the action of the Commissioner is quasi-judicial, the fact that no appeal is expressly given to the Secretary is conclusive that none is to be implied."
We perceive no ground for overruling that case or dissenting from the reasoning of the opinion; and as the proceeding in the Court of Appeals on an appeal in an interference controversy presents all the features of • a civil case, a plaintiff, a defendant and a judge, and deals with a question judicial in its nature, in respect of which the judgment of the court is final so far as the particular action of the Patent Office is concerned, such judgment is none the less a judgment " because its effect may be to aid an administrative or executive body in the performance of duties legally imposed upon it by Congress in execution of a power granted by the Constitution." Interstate Commerce Commission v. Brimson, 154 U. S. 447.
It will have been seen that in the gradual development of the policy of Congress in dealing with the subject of patents, the recognition of the judicial character of the questions involved became more and more pronounced.
By the acts of 1839 and 1852 an appeal was given, not to the Circuit Court of the District of Columbia, but to the chief judge or one of the assistant judges thereof, who was thus called on to act as a special judicial tribunal. The competency of Congress to make use of such an instrumentality or to create such a tribunal in the attainment of the ends of the Patent Office seems never to have been questioned, and we think could not have been successfully. The nature of the thing to be done being judicial, Congress had power to provide for judicial interference through a special tribunal, United States v. Coe, 155 U. S. 76; and a fortiori existing courts of competent jurisdiction might be availed of.
We agree that it is of vital importance that the line of demarcation be+ween the three great departments of govern-' ment should be observed, and that each should be limited to the exercise of its appropriate powers, but in the matter of this appeal we find no such encroachment of one department on the domain of another as to justify us in holding the act in question unconstitutional.
Judgment affirmed.