Relators request a writ of prohibition and/or mandamus to prevent the Court of Claims from exercising further jurisdiction over the underlying case, to compel the Court of Claims to vacate its entries granting the defendants/third-party plaintiffs’ Civ.R. 60(B) motion and reinstating the case, and to order the Court of Claims to remand the case to the Montgomery County Court of Common Pleas for a trial on the merits.
Relators assert in their first proposition of law that if the state is found not liable to a plaintiff for the reckless actions of a defendant, the state cannot be held liable to a third-party defendant under a claim of contribution or indemnity arising out of the same transaction.
Neither prohibition nor mandamus will lie where relators possess an adequate remedy in the ordinary course of law. State ex rel. Hunter v. Certain Judges of the Akron Mun. Court (1994), 71 Ohio St.3d 45, 46, 641 N.E.2d 722, 723. In addition, neither mandamus nor prohibition may be employed as a substitute for an appeal from an interlocutory order. State ex rel. Keenan v. Calabrese (1994), 69 Ohio St.3d 176, 178, 631 N.E.2d 119, 121. The court of appeals determined that the Court of Claims’ entry vacating its prior dismissal and instructing its clerk to place the matter on the active docket was an interlocutory order.
Absent a patent and unambiguous lack of jurisdiction, a court having general subject-matter jurisdiction can determine its own jurisdiction, and a party challenging the court’s jurisdiction has an adequate remedy at law by appeal. State ex rel. Enyart v. O’Neill (1995), 71 Ohio St.3d 655, 656, 646 N.E.2d 1110, 1112. Relators contend that because the Court of Claims patently and unambiguously lacks jurisdiction over the underlying case, appeal is not an adequate remedy, and prohibition and mandamus will lie. State ex rel. Lewis v. Moser (1995), 72 Ohio St.3d 25, 28, 647 N.E.2d 155, 157 (writ of prohibition may issue *556despite an available appeal where a court has no jurisdiction whatsoever to act); State ex rel. Ballard v. O’Donnell (1990), 50 Ohio St.3d 182, 184, 553 N.E.2d 650, 652 (writ of mandamus may compel vacation of court order, notwithstanding an available appeal, where the lower court had no jurisdiction to act).
R.C. 2743.03(A)(1) provides that the Court of Claims “has exclusive, original jurisdiction of all civil actions against the state permitted by the waiver of immunity contained in section 2743.02 of the Revised Code, exclusive jurisdiction of the causes of action of all parties in civil actions that are removed to the court of claims, and jurisdiction to hear appeals from the decisions of the court of claims commissioners.” (Emphasis added.)
R.C. 2743.03(E) provides:
“(1) A party who files a counterclaim against the state or makes the state a third-party defendant in an action commenced in any court, other than the court of claims, shall file a petition for removal in the court of claims. The petition shall state the basis for removal, be accompanied by a copy of all process, pleadings, and other papers served upon the petitioner, and shall be signed in accordance with Civil Rule 11. * * *
“(2) Within seven days after filing a petition for removal, the petitioner shall give written notice to the parties, and shall file a copy of the petition with the clerk of the court in which the action was brought originally. The filing effects the removal of the action to the court of claims, and the clerk of the court where the action was brought shall forward all papers in the case to the court of claims. The court of claims shall adjudicate all civil actions removed. The court may remand a civil action to the court in which it originated upon a finding that the removal petition does not justify removal, or upon a finding that the state is no longer a party.” (Emphasis added.)
Relators assert that a remand of the case to the common pleas court was required following the determination by the court of appeals that Dr. Seifer was not entitled to R.C. 9.86 immunity, and that the Court of Claims thereafter patently and unambiguously lacked jurisdiction. However, the Court of Claims possessed exclusive jurisdiction pursuant to R.C. 2743.03(A)(1) over the underlying case when it was removed. Further, under R.C. 2743.03(E)(2), remand to the common pleas court is permissive rather than mandatory. Nease v. Med. College Hosp. (1992), 64 Ohio St.3d 396, 399, 596 N.E.2d 432, 435. The Court of Claims is not required to remand a case upon a finding that the state is no longer a party. Id. Here, there was not even a finding that the state is no longer a party. The cases relied upon by relators to support their assertion of a mandatory duty, see, e.g., Tschantz v. Ferguson (1991), 57 Ohio St.3d 131, 133, 566 N.E.2d 655, 657, are inapposite, since they do not involve the Court of Claims’ removal jurisdiction under R.C. 2743.03(A)(1) and 2743.03(E).
*557As to relators’ claim that “[t]he findings of the Court of Appeals, and subsequent finding by the Court of Claims, [are] res judicata and the law of the case,” writs of mandamus and prohibition are appropriate to require lower courts to comply with and not proceed contrary to the mandate of a superior court. State ex rel. Smith v. O’Connor (1995), 71 Ohio St.3d 660, 662, 646 N.E.2d 1115, 1117. However, the Court of Claims complied with the mandate of the court of appeals by issuing an entry specifying that Dr. Seifer was not entitled to R.C. 9.86 immunity. In fact, when relators attempted to obtain a directive from the court of appeals to compel the Court of Claims to dismiss the case because of the appellate court’s decision, that court expressly held that the state was not automatically removed as a party to the action and that dismissal of the Court of Claims lawsuit was “not necessarily appropriate.” Therefore, no court, including the Court of Claims, has yet determined that the state is no longer a party.
Based on the foregoing, relators’ initial argument does not evidence a patent and unambiguous lack of jurisdiction on the part of the Court of Claims, and relators have not established how a postjudgment appeal would otherwise be inadequate. See, e.g., State ex rel. Willis v. Sheboy (1983), 6 Ohio St.3d 167, 6 OBR 225, 451 N.E.2d 1200, paragraph one of the syllabus (“Where a constitutional process of appeal has been legislatively provided, the sole fact that pursuing such process would encompass more delay and inconvenience than seeking a writ of mandamus is insufficient to prevent the process from constituting a plain and adequate remedy in the ordinary course of the law.”). Therefore, relators’ first proposition does not warrant extraordinary relief and is overruled.
The Court of Claims contends that this court should not consider the merits of relators’ remaining propositions of law because relators “did not raise these arguments as * * * grounds for relief in their complaint, nor did they amend their complaint to include such arguments as is required by [Civ.R.] 15.” However, no amendment was necessary, since relators’ second proposition relied on factual allegations contained in the complaint, and their third proposition, which was premised on facts occurring after the complaint, did not modify either the amount or nature of the relief sought in the original complaint. See Staff Notes to Civ.R. 15(E). Further, we have held in mandamus actions that “a court is not limited to considering facts and circumstances at the time a proceeding is instituted, but should consider the facts and conditions at the time it determines to issue a peremptory writ.” Oregon v. Dansack (1993), 68 Ohio St.3d 1, 4, 623 N.E.2d 20, 22. Thus, the court should consider the merits of relators’ remaining propositions.
Relators assert in their second proposition of law that a third-party claim against the state for contribution and/or indemnity does not vest removal jurisdiction in the Court of Claims where the third-party plaintiff cannot prose*558cute such claim and the Court of Claims cannot rule on the claim. Relators contend that since a claim of contribution and/or indemnity does not vest until after, at least, the final judgment, the Court of Claims lacks removal jurisdiction. Contribution and indemnity claims are prevalent in third-party practice. See, generally, McCormac, Ohio Civil Rules Practice (2 Ed.1992) 210-212, Section 8.22. Neither R.C. 2743.03(A)(1) nor 2743.03(E) distinguishes between “vested” and “contingent” third-party claims. Consequently, for the same reasons discussed in our disposition of relators’ first proposition of law, jurisdiction in the Court of Claims is not patently and unambiguously lacking under R.C. 2743.03(A)(1) and 2743.03(E)(2), and relators have not established the inadequacy of postjudgment appeal as an alternative remedy. Relators’ second proposition is overruled.
Relators claim in their third proposition of law that the Court of Claims patently and unambiguously lacked jurisdiction to vacate its dismissal under Civ.R. 60(B) while appeals were pending. When a case has been appealed, the trial court retains all jurisdiction not inconsistent with the reviewing court’s jurisdiction to reverse, modify, or affirm the judgment. Yee v. Erie Cty. Sheriffs Dept. (1990), 51 Ohio St.3d 43, 44, 553 N.E.2d 1354, 1355.
An appeal from a judgment divests trial courts of jurisdiction to consider Civ.R. 60(B) motions for relief from judgment, and jurisdiction to consider such motions may be conferred on the trial court only through an order of the reviewing court. Howard v. Catholic Social Serv. of Cuyahoga Cty., Inc. (1994), 70 Ohio St.3d 141, 147, 637 N.E.2d 890, 895; State ex rel. E. Mfg. Corp. v. Ohio Civ. Rights Comm. (1992), 63 Ohio St.3d 179, 181, 586 N.E.2d 105, 107. The Court of Claims therefore lacked jurisdiction to render its September 28, 1994 entry vacating its previous dismissal judgment when the dismissal was being appealed. Nevertheless, after the appeal was dismissed, the court had jurisdiction to rule on the Civ.R. 60(B) motion, which it did on October 28, 1994 by refiling its earlier vacation entry.
Relators claim that this reinstated entry was also entered without jurisdiction because their appeal from the earlier vacation entry was pending. However, since the mere reinstatement of the vacation entry was not an exercise of jurisdiction inconsistent with the court of appeals’ jurisdiction to review the first vacation entry, the pendency of that appeal did not divest the Court of Claims of jurisdiction to reinstate its Civ.R. 60(B) ruling. See Howard and Yee, supra. Further, relators concede that their appeal has since been dismissed. Relators’ third proposition is meritless.
Since it is evident that the Court of Claims does not patently and unambiguously lack jurisdiction over the underlying case and relators have not established *559that a postjudgment appeal constitutes an inadequate alternate remedy, relators are not entitled to extraordinary relief.
Accordingly, the writs of prohibition and mandamus are denied.
Writs denied.
Moyer, C.J., Douglas, Wright, Resnick, F.E. Sweeney, Pfeifer and Cook, JJ., concur.