Appellant Paul Giragosian owned and operated a gun shop in Arlington, Massachusetts for approximately thirty-one years. In March 2007, Arlington’s Chief of Police, Frederick Ryan, revoked and forfeited appellant’s licenses to carry and sell firearms. Subsequently, appellant filed a 42 U.S.C. § 1983 suit in federal district court alleging that Ryan and the Town of Arlington violated his rights under the Fourth and Fourteenth Amendments. The district court granted appel-lees’ motion to dismiss.
The issues before us on appeal are (1) whether appellant’s § 1983 claims are barred by res judicata, and (2) whether the district court erred by converting appel-lees’ motion to dismiss into a motion for summary judgment. We have jurisdiction pursuant to 28 U.S.C. § 1291 and affirm on the basis of claim preclusion. 1
I.
In addition to selling firearms at his gun shop in Arlington, Massachusetts, appellant conducted training sessions on the use of firearms. In January 2007, while appellant was training a customer to use a handgun, the customer intentionally shot himself in the head, dying as a result of the wound.
On the same day of the incident, the Arlington Police Department conducted an investigation and concluded that appellant was not at fault for the customer’s suicide. One day later, appellee Frederick Ryan, Arlington’s Chief of Police, suspended appellant’s licenses to carry and sell firearms, pursuant to Massachusetts General Laws chapter 140, pending further investigation by the Arlington Police Department and the Middlesex County District Attorney’s Office. Ryan also requested that the United States Bureau of Alcohol, Tobacco, Firearms and Explosives (“ATF”) investi *62 gate appellant’s business for any potential violations of federal law.
Appellant subsequently challenged the suspension of his licenses in Massachusetts state court. In March 2007, after the Arlington Police Department and the Middle-sex District Attorney completed their investigations confirming that appellant was not at fault for the customer’s suicide, the Cambridge District Court granted appellant’s request to vacate the license suspensions.
Rather than reinstating the licenses, Ryan sent a letter to appellant revoking appellant’s licenses to carry firearms and forfeiting his dealer licenses. Ryan’s letter listed several reasons for the revocations and forfeitures, including, but not limited to, (1) failure to report stolen firearms, (2) failure to undergo a firearms safety instructor course mandated by the Massachusetts state court following a similar customer suicide in 2002, and (3) various violations of state and federal law found during the ATF investigation requested by Ryan. 2
In April 2007, appellant filed a § 1983 action in federal district court alleging Ryan and the Town of Arlington violated his Fourth Amendment right to be free from unreasonable searches and seizures, as well as his Fourteenth Amendment due process rights. Appellant sought reinstatement of his firearms licenses pursuant to Massachusetts law and damages under § 1983. One day later, appellant filed a separate action in state court also seeking reinstatement of his firearms licenses.
In May 2007, as the state and federal actions proceeded simultaneously, appellant filed a motion in federal district court for a temporary restraining order (“TRO”) to enjoin the state court from ruling until the conclusion of the federal case. Appellant argued that the state court judge “greeted Defendant Ryan with an excess of cordiality,” demonstrating the state court’s “bias and favoritism” towards Ryan. The district court denied appellant’s motion.
In June 2007 the state court refused reinstatement of appellant’s licenses, finding “sufficient grounds to conclude that the decision of [Ryan] in revoking [appellant’s] firearms licenses was reasonable and not arbitrary, capricious or an abuse of discretion.” See Giragosian v. Ryan, No. 07-10730 (Mass. Dist. Ct. June 7, 2007). Following the state-court’s ruling, a federal magistrate judge requested supplemental briefing from the parties regarding the state-court judgment’s effect on appellees’ pending motion to dismiss. Appellees’ argued in their supplemental memorandum that the state-court judgment barred appellant’s federal cause of action pursuant to the doctrine of res judicata (both issue and claim preclusion). Appellant argued the federal district court should ignore the state-court judgment because of the state court judge’s lack of impartiality and numerous errors of law.
In August 2007, the federal magistrate judge recommended the district court grant appellees’ Rule 12(b)(6) motion to dismiss. The magistrate judge ruled (1) issue preclusion barred the federal district court from reexamining whether Ryan’s actions were arbitrary, capricious, or an abuse of discretion, (2) the post-deprivation review process available in state court provided appellant adequate process, and *63 (3) qualified immunity shielded Ryan and the Town of Arlington from suit. The district court rejected the magistrate judge’s recommendation as to qualified immunity. The district court ruled that the federal magistrate judge relied on information outside the four corners of the complaint in finding qualified immunity. Thus, that issue could only be resolved on a motion for summary judgment. The district court, however, agreed with the magistrate judge’s conclusion that appellant failed to “state a cause of action for a violation of due process rights under the Fourteenth Amendment to the Constitution or Fourth Amendment rights.” Accordingly, the district court granted appel-lees’ motion to dismiss.
II.
The issues we address on appeal concern the legal sufficiency of appellant’s complaint. Our review, therefore, is
de novo. See Torromeo v. Town of Fremont,
A.
We first consider whether appellant’s § 1983 action is barred by the doctrine of res judicata. “Disposition of [a] federal action, once [a] state-court adjudication is complete, [is] governed by preclusion law.”
Exxon Mobil Corp. v. Saudi Basic Indus. Corp.,
In Massachusetts, res judicata encompasses both claim preclusion and issue preclusion.
Id.
(citing
Kobrin v. Bd. of Registration in Med.,
While Massachusetts’ case law does not directly address the relevance of the order in which parallel actions are filed, the general rule is that “when two actions are pending which are based on the same claim, or which involve the same issue, it is the final judgment first rendered in one of the actions which becomes conclusive in the other action ..., regardless of which action was first brought.” Restatement (Second) of Judgments § 14, cmt. a (1982);
see also Blair v. Equifax Check Servs., Inc.,
While parallel litigation may-force a court to “recognize the claim- and issue-preclusive effects of a state-court judgment, ... federal jurisdiction over an action does not terminate automatically on the entry of judgment in the state court.”
Exxon Mobil,
With such concerns in mind, we proceed to consider the applicability of claim preclusion to the present ease.
3
Following the revocations and forfeitures of his various licenses, appellant chose to pursue relief in both state and federal court. Of course, appellant could have pursued all of his claims in a single suit in either forum. In his federal complaint and subsequent memoranda in opposition to appellees’ motion to dismiss, appellant requested the federal court exercise pendent jurisdiction over appellant’s state claim (the review for reasonableness of the license revocations pursuant to Mass. Gen. Laws ch. 140 § 131(f) and § 122). Appellant also admitted at oral argument that he could have filed his § 1983 claim in state court. Accordingly, we employ Massachusetts’ three part test to determine whether claim preclusion applies.
See McDonough,
All three elements required for claim preclusion under Massachusetts law are easily satisfied here. First, the identity of the parties in the state and federal actions are the same. See id. Second, the facts described in both the state and federal complaints are identical, leaving no doubt that the two causes of action “derive[] from the same transaction or series of connected transactions.” Id. In other words, the only transaction at issue in both the state and federal actions is Ryan’s revocation and forfeiture of appellant’s licenses. Third, prior to the conclusion of the federal proceeding, the state court issued a “final judgment on the merits” when it determined that Ryan reasonably revoked appellant’s firearms licenses. Id.
Appellant appears to have recognized the potential problem with pursuing simultaneous actions in state and federal court, as he requested a TRO from the district court enjoining a possible state-court judgment. Appellant similarly requested the state court delay its decision until the conclusion of his federal action. At the very least, appellant understood that a federal court would not be able to reinstate his licenses, under state law, if the state court first rendered its own decision.
In support of his TRO, appellant argued he was concerned about bias because of the state court judge’s cordial reception of Ryan at the initial state-court proceeding. Such a slight and subjective concern does not warrant disregard for a prior, valid,
*65
state-court judgment. We have already-rejected the notion that “ ‘distrust of state courts ... would justify a limitation on the preclusive effect of state judgments.’ ”
Willhauck, v. Halpin,
Appellant had a full and fair opportunity to litigate his § 1983 claim in state court.
See Mulrain v. Bd. of Selectmen,
Because appellant voluntarily proceeded in both forums, he is now subject to the consequences of claim preclusion. No unfairness attends this result as “the splitting of [appellant’s] claims was voluntary” and appellant was “fully aware of them.”
Hayes v. Town of Orleans,
39 Mass.App.Ct.682,
B.
Appellant argues the district court improperly converted his motion to dismiss into a motion for summary judgment without providing adequate notice and an opportunity to be heard. When ruling on a Rule 12(b)(6) motion to dismiss, a district court is generally limited to considering “facts and documents that are part of or incorporated into the complaint.”
Trans-Spec Truck Serv., Inc. v. Caterpillar Inc.,
Appellant argues the district court improperly considered materials outside of the complaint in ruling on his motion to dismiss. Appellant contends the district court should not have considered, absent a *66 summary judgment hearing, (1) the ATF report outlining appellant’s violations of law, and (2) appellant’s rebuttal to the Rule 12(b)(6) motion. We need not consider whether the district court properly referenced these documents, however, because we have dismissed appellant’s claims on the basis of res judicata. The only materials necessary to support this ruling are the documents pertaining to the state-court judgment against appellant.
A court may consider matters of public record in resolving a Rule 12(b)(6) motion to dismiss.
In re Colonial Mortgage,
For the foregoing reasons, the judgment of the district court is affirmed.
Notes
. Appellant also argues the district court erred in ruling that he failed to state a cause of action under the Fourth and Fourteenth Amendments. We do not address this issue, however, because we hold that appellant's federal action is barred by the doctrine of res judicata.
. The ATF report noted that appellant (1) manufactured ten firearms without a manufacturing license, (2) failed to contact the FBI for a background check prior to the sale of six firearms, (3) failed to report the sale of multi-pie handguns to three individuals, and (4) failed to properly document the gun shop's and appellant's personal inventory of firearms.
. While the district court dismissed appellant's suit on alternate grounds, we focus our discussion on claim preclusion.
See Cook v. Gates,
