SUMMARY ORDER

UPON DUE CONSIDERATION, IT IS HEREBY ORDERED, ADJUDGED AND DECREED that the judgment of said district court be and it hereby is AFFIRMED.

Plaintiff-appellant George Hom, pro se, appeals from the March 12, 2001 judgment in favor of defendant and the April 18, 2001 denial of his motion for reconsideration entered by the United States District Court for the Eastern District of New York (Platt, D.J.).

In February 2000, Hom filed suit against defendant Marc C. Reubins, M.D., alleging, inter alia, that Reubins had engaged in a conspiracy to “impede and obstruct justice” in the then-pending state case of Hom v. Reubins, New York Supreme Court Index No. 97-032076, by offering false testimony and making deliberate efforts to deny plaintiff due process. Plaintiffs allegations against Reubins arise out of two state court actions: (1) a custody dispute in which defendant conducted court-ordered examinations of Horn, his children, and his former wife to determine the best interests of Hom’s children; and (2) a subsequent state court action, Hom v. Reubins, New York Supreme Court Index No. 97-032076 (“Hom v. Reubins”), in which Horn asserted various claims against defendant, including the allegation that Reubins’s actions in the custody dispute caused Hom to be deprived of his right to a fair trial.

Plaintiff’s pro se federal complaint largely recounts the history of Hom v. Reubins, culminating in the claims that Reubins’s actions caused significant damage to plaintiff and his family and that, due to the relationship between Reubins and the New York state government and the Nassau County judicial and political community, “it is apparent that [Hom] could never get justice in the Courtrooms of the State of New York.”

The district court granted defendant’s motion to dismiss on March 7, 2001, concluding that (1) the federal district court lacked subject matter jurisdiction under the Rooker-Feldman doctrine; (2) Younger abstention was appropriate; (3) principles of res judicata bar the suit; and (4) plaintiff had not alleged facts sufficient to establish that defendant was a state actor for purposes of § 1983. Judgment was entered against plaintiff on March 12, 2001; he thereafter filed a motion for reconsideration, which was denied April 18, 2001.

We review a district court’s grant of a motion to dismiss for lack of subject mat*106ter jurisdiction de novo. Rivers v. McLeod, 252 F.3d 99, 101 (2d Cir. 2001) (per curiam). Likewise, we review de novo a district court’s grant of a motion to dismiss under Federal Rule of Civil Procedure 12(b)(6) for failure to state a claim. Gregory v. Daly, 243 F.3d 687, 691 (2d Cir. 2001). For the following reasons, we affirm the district court’s dismissal of plaintiffs complaint.

A generous reading of Horn’s pro se complaint reveals two basic types of due process claims brought under 42 U.S.C. § 1983:(1) claims arising out of the custody dispute in which Reubins was appointed by the court to prepare a report; and (2) claims that Reubins engaged in various efforts to deprive plaintiff of due process during the pendency of Hom v. Reubins.

Insofar as plaintiffs complaint states claims arising out of Reubins’s actions in the state court custody proceeding, they are barred by the Rooker-Feldman doctrine, which establishes an important limitation on the subject matter jurisdiction of the district court. Stated simply, “a United States District Court has no authority to review final judgments of a state court in judicial proceedings.” D.C. Court of Appeals v. Feldman, 460 U.S. 462, 482, 103 S.Ct. 1303, 75 L.Ed.2d 206 (1983); see Rooker v. Fidelity Trust Co., 263 U.S. 413, 44 S.Ct. 149, 68 L.Ed. 362 (1923). Under Rooker-Feldman, a federal court “lacks jurisdiction over any claims that are ‘inextricably intertwined’ with a state court’s determinations in a judicial proceeding.” Hachamovitch v. DeBuono, 159 F.3d 687, 694 (2d Cir. 1998) (quoting Feldman, 460 U.S. at 482 n. 16, 103 S.Ct. 1303).

We have interpreted “inextricably intertwined” to mean “at a minimum, that where a federal plaintiff had an opportunity to litigate a claim in a state proceeding ... subsequent litigation of the claim will be barred under the Rooker-Feldman doctrine if it would be barred under the principles of preclusion.” Moccio v. New York State Office of Court Admin., 95 F.3d 195, 199-200 (2d Cir. 1996). Accordingly, under Moccio, the application of Rooker-Feldman turns on the question of whether collateral estoppel would apply, i.e., whether “(1) the issue in question was actually and necessarily decided in a prior proceeding, and (2) the party against whom the doctrine is asserted had a full and fair opportunity to litigate the issue in the first proceeding.” Colon v. Coughlin, 58 F.3d 865, 869 (2d Cir. 1995) (applying New York law). We conclude that plaintiffs claims regarding Reubins’s alleged misconduct in the state custody proceeding are inextricably intertwined with the state court case of Horn v. Reubins, and that the district court was therefore correct in concluding there is no federal subject matter jurisdiction with respect to those claims.

In contrast, Hom’s claims relating to Reubins’s conduct during the pendency of the Hom v. Reubins proceedings were not previously litigated in state court and are therefore not barred under Rooker-Feldman. With respect to these allegations, however, plaintiff has failed to allege any facts to support a finding that Reubins engaged in state action as required under § 1983. See Giordano v. City of New York, 274 F.3d 740, 750 (2d Cir. 2001) (“To state a cause of action under § 1983, [plaintiff] must allege (1) that the defendants deprived him of a right secured by the Constitution or laws of the United States; and (2) that they did so under color of state law.” (internal quotation marks omitted)). Although Horn claims that “Dr. Reubins is an officer of the court,” he alleges no facts to support the conclusion that Reubins acted under color of state law in his capacity as a private-party defendant in Hom v. Reu*107bins. As such, Horn failed to state a claim under § 1988 arising out of the state court lawsuit and the district court’s dismissal of those claims was proper.1

We have carefully considered plaintiffs remaining arguments and consider them to be without merit.

For the foregoing reasons, the judgment of the district court is AFFIRMED.