726 Opinion of the Court. tioner and his attorney in the suit in which the judgment was rendered denied the allegations of fraud. The district court denied the motion, and the Court of Appeals for the Ninth Circuit affirmed. 111 F.2d 310. It overruled all the alleged grounds for setting aside the judgment, holding that the service of process was valid and that in any case the defendant had appeared in the suit by entering into the stipulation for trial of the issue of value of the property alleged to have been converted and participating in the hearing on that issue. It also held that the charge of fraud was denied and unsupported by proof, adding "that ground of appellants' motion appears to have been abandoned." There was no review of this decision. The court below, in rejecting petitioner's plea of res judicata, and in directing inquiry into the merits of the original cause of action and into the allegation of fraud in procurement of the judgment, rested its decision upon the ground that the bankrupt's trustee had failed to place before the California district court any contention or proof that petitioner's testimony, particularly as to the value of the converted property, was perjured, that the bankrupt was not indebted to petitioner, or that the allegations of the complaint were untrue. The court, relying on Pepper v. Litton, supra, also held that the bankruptcy court, being a court having equity powers, was not bound by the principles of res judicata as to issues which were not pressed before the California district court, and that the authority of the bankruptcy court as a court of equity included the power to inquire into the validity of the claim upon which the judgment, presented as a claim against the estate, was based. We need not consider whether, apart from the requirements of the full faith and credit clause of the Constitution, the rule of res judicata applied in the federal courts, in diversity of citizenship cases, under the doctrine of Opinion of the Court. 327 U.S. Erie R. Co. v. Tompkins, 304 U. S. 64; cf. Guaranty Trust Co. v. York, 326 U. S. 99; Holmberg v. Armbrecht, 327 U. S. 392, can be other than that of the state in which the federal court sits. For nothing decided in Erie R. Co. v. Tompkins, supra, requires a court of bankruptcy, in applying the statutes of the United States governing the liquidation of bankrupts' estates, to adopt local rules of law in determining what claims are provable, or to be allowed, or how the bankrupt's estate is to be distributed among claimants. Cf. Board of Comm'rs v. United States, 308 U. S. 343; Deitrick v. Greaney, 309 U. S. 190; D'Oench, Duhme & Co. v. F. D. I. C., 315 U. S. 447; Helvering v. Stuart, 317 U. S. 154, 161-2; Sola Electric Co. v. Jefferson Co., 317 U. S. 173, 176; Wragg v. Federal Land Bank, 317 U. S. 325, 328; Clearfield Trust Co. v. United States, 318 U.S. 363. In passing upon and rejecting or allowing the proof of claim in this case the court of bankruptcy proceeds-not without appropriate regard for rights acquired under state law-under federal statutes which govern the proof and allowance of claims based on judgments. In determining what judgments are provable and what objections may be made to their proof; and in determining the extent to which the inequitable conduct of a claimant in acquiring or asserting his claim in bankruptcy, requires its rejection or its subordination to other claims which, in other respects are of the same class, the bankruptcy court is defining and applying federal, not state, law. See Prudence Realization Corp. v. Geist, supra, 95, 96 and cases cited; cf. United States v. Pelzer, 312 U. S. 399, 402-03. It is true that a bankruptcy court is also a court of equity, Local Loan Co. v. Hunt, 292 U. S. 234, 240, and may exercise equity powers in bankruptcy proceedings to set aside fraudulent claims, including a fraudulent judgment where the issue of fraud has not been previously adjudicated. Pepper v. Litton, supra, 306. In appro 726 Opinion of the Court. priate cases, acting upon equitable principles, it may also subordinate the claim of one creditor to those of others in order to prevent the consummation of a course of conduct by the claimant which, as to them, would be fraudulent or otherwise inequitable. Taylor v. Standard Gas Co., 306 U. S. 307; Pepper v. Litton, supra; Prudence Realization Corp. v. Geist, supra; American Surety Co. v. Sampsell, 327 U. S. 269. But we are aware of no principle of law or equity which sanctions the rejection by a federal court of the salutary principle of res judicata, which is founded upon the generally recognized public policy that there must be some end to litigation and that when one appears in court to present his case, is fully heard, and the contested issue is decided against him, he may not later renew the litigation in another court. Baldwin v. Traveling Men's Assn., 283 U. S. 522, 525–6. Before Erie R. Co. v. Tompkins it was recognized by this Court that, apart from the full faith and credit clause, a judgment duly rendered in one court will be recognized as res judicata in a suit between the same parties in a federal court. Cromwell v. County of Sac, 94 U. S. 351; Case v. Beauregard, 101 U. S. 688; Baltimore S. S. Co. v. Phillips, 274 U. S. 316; Grubb v. Public Utilities Comm'n, 281 U. S. 470. See Baldwin v. Traveling Men's Assn., supra, and cases cited; cf. Chicago, R. I. & P. R. Co. v. Schendel, 270 U. S. 611; Milwaukee County v. White Co., 296 U. S. 268, 272-3. It has been held in non-diversity cases, since Erie R. Co. v. Tompkins, that the federal courts will apply their own rule of res judicata. Sunshine Coal Co. v. Adkins, 310 U. S. 381, 403; Jackson v. Irving Trust Co., 311 U. S. 494, 503. This Court has also required that effect be given in both state and federal courts to a plea of res judicata arising from decrees of a bankruptcy court. Stoll v. Gottlieb, 305 U. S. 165; Chicot County Dist. v. Bank, 308 U. S. 371. And it is well settled that where the trustee in bankruptcy unsuccessfully litigates an issue out Opinion of the Court. 327 U.S. side the bankruptcy court the decision against him is binding in the bankruptcy court. Davis v. Friedlander, 104 U. S. 570; Fischer v. Pauline Oil Co., 309 U. S. 294, 302-03. At least to the extent that the issue of fraud raised by the objections to petitioner's claim as between petitioner and the bankrupt has been litigated and decided before the bankruptcy and has since been litigated between the petitioner and the trustee in bankruptcy, who represents the bankrupt and his creditors, that issue is now res judicata and may not further be litigated in the bankruptcy proceeding. Hence we turn to the question, what issues essential to the allegations that the judgment was procured by fraud have been so litigated. Examination of the record in this proceeding, including the objections filed to petitioner's claim, the applications of the bankrupt, the trustee, and the creditors, for authority to attack the judgment in the District Court of Southern California, and the proceedings instituted in that court for that purpose, make plain the nature of the fraud charged against petitioner. Shortly stated it is that in the course of transactions with petitioner the bankrupt acquired possession of and converted to his own use a quantity of worthless minerals, owned or previously owned or possessed by petitioner, who, by means of perjured allegations in the complaint and perjured testimony as to their amount and value, procured a default judgment against the bankrupt for an amount in excess of their value. It is evident that an essential element of the claim of fraud is that the alleged converted minerals were worth substantially less than the $164,000 alleged to be their value in the complaint, for which the judgment was rendered. But before the bankruptcy this issue of value had been litigated between petitioner and the bankrupt in the District Court for Southern California. In the course of the proceedings had on the bankrupt's motion to set aside the judgment, the district court decided the issue 726 Opinion of the Court. against the bankrupt and declined to disturb the judgment. No appeal was taken from the judgment and consequently there was no review of the denial of the bankrupt's motion to set aside or modify the judgment, or of the court's minute order finding that the converted gems were of the value alleged in the complaint. The same issue as to value and also the issue whether there was perjured testimony of value were raised in the proceeding later brought in the District Court for Southern California by the trustee in behalf of the bankrupt to set aside the judgment. In his application to the bankruptcy court to direct the trustee to bring the proceeding, the bankrupt had represented that "the material allegations of the complaint filed in said case [in the District Court for Southern California] are untrue"; that "the raw gems described in plaintiff's complaint were at no time of the value of $164,000.00 or any comparable value”. As already noted the papers on the motion in behalf of the trustee and the bankrupt to vacate the judgment, set up that the judgment was based on "fictitious values" and was fraudulently procured. In that proceeding the charge of fraud thus alleged was put in issue by the answering affidavits. The denial of the motion by the district court was affirmed by the Court of Appeals for the Ninth Circuit on the ground that the applicants had not sustained their allegations of fictitious value and fraud by any tender of evidence or other proof. This was a final judgment on the issues thus raised, binding on the parties to the proceeding. It is not any the less so, as the Court of Appeals thought, because the moving parties failed to support their allegations by evidence. In general a judgment is res judicata not only as to all matters litigated and decided by it, but as to all relevant issues which could have been but were not raised and litigated in the suit. Cromwell v. County of Sac, supra, 352; Grubb v. Public Utilities Comm'n, supra, 479; Chicot |