*1094I. INTRODUCTION
Victor Guerrero, a Mexican immigrant and aspiring California correctional officer, filed a federal action alleging discriminatory failure-to-hire against the California Department of Corrections and Rehabilitation (the CDCR), among other defendants. He pled federal and state law claims, but only his state claims allowed him to seek general damages.
The federal court dismissed Guerrero's state claims on Eleventh Amendment grounds, effectively limiting his potential money recovery to the equitable remedy of backpay. To recoup damages, Guerrero filed this action in superior court. After final judgment was entered in the federal action-in Guerrero's favor-the superior court dismissed his state claims under California claim preclusion principles.
On appeal, Guerrero now argues that federal law, not California law, governs the preclusive effect of the federal judgment. Under federal law, Guerrero contends, there is a well-recognized exception to claim preclusion rules where jurisdictional limitations in a prior suit blocked the plaintiff's request for complete relief, as was the case here. We agree and shall reverse.
II. FACTS
A. Background
Guerrero is among the many Americans who are popularly known as "Dreamers." He was brought from Mexico to the United States by his parents in 1990 at age 11. In 1995, at age 15, he created a false Social Security number (SSN) to acquire a job, and used the made-up SSN until 2007, when he secured a legitimate SSN. He became a United States citizen in 2011.
After Guerrero gained citizenship, he applied to become a correctional officer with the CDCR. He passed the written and physical exams in the first stage of the *729CDCR's eligibility process and was placed on the eligibility list. The second stage involved completing the CDCR's background investigation questionnaire.
Question 75 on the questionnaire presented a problem. It asked, "Have you ever had or used a social security number other than the one you used on this *1095questionnaire?" Guerrero answered "yes" and provided a supplemental explanation. Based on that answer, the CDCR informed Guerrero he was no longer eligible to become a correctional officer.
Undaunted, Guerrero appealed to the State Personnel Board (the SPB), lost, and then reapplied to the CDCR in spring 2013. He again passed the first stage of eligibility and moved on to the background investigation questionnaire. Once again, he answered "yes" to question 75 and provided an explanation. Ultimately, he was rejected again. He appealed to the SPB, to no avail.
B. Underlying Litigation
1. Filing of the Federal Action
After exhausting administrative remedies, Guerrero filed a complaint in federal district court on December 9, 2013 (the Federal Action), naming the CDCR, the SPB and various individuals as defendants. That case alleged employment discrimination in violation of title VII of the Civil Rights Act of 1964 (Title VII) and California's Fair Employment and Housing Act ( Gov. Code, § 12940 et seq. ) (FEHA); national origin discrimination in a state-conducted program in violation of Government Code section 11135 ; federal constitutional claims under section 1983 of title 42 of the United States Code for violation of the equal protection and due process clauses of the United States Constitution; and state constitutional claims for violation of the equal protection and due process clauses of article I, section 7 of the California Constitution.
By way of relief, Guerrero sought, inter alia, declaratory relief, injunctive relief (including reinstatement to the CDCR correctional officer hiring process), compensatory damages, and an award of attorney fees and costs. He bolstered this requested relief with claims for a writ of mandate under Code of Civil Procedure section 1085 barring further use of question 75; and a writ of administrative mandamus under Code of Civil Procedure section 1094.5 directing the CDCR and the SPB to set aside their decisions declaring him ineligible to be a correctional officer.
2. Dismissal of State Law Claims in the Federal Action
As the Federal Action moved forward, Guerrero added specificity, filing a first amended complaint in January 2014 and then a second amended complaint in February 2014. On motions to dismiss the second amended complaint, the district court granted dismissal in part. The court rejected the *1096defense's attack on the Title VII and federal equal protection claims; dismissed the federal due process claim as redundant in light of the more specific equal protection claim; and dismissed the state law claims on Eleventh Amendment grounds, without prejudice. ( Guerrero v. California Department of Corrections and Rehabilitation (N.D.Cal. 2015) 119 F.Supp.3d 1065, 1068-1069 ( Guerrero I ), affirmed in part, reversed in part, and remanded Guerrero v. California Department of Corrections and Rehabilitation (9th Cir. 2017) 701 Fed.Appx. 613 ( Guerrero II ).)
The order of dismissal explained that "[b]ecause adjudication of plaintiff's California state-law claims in federal court would contravene the Eleventh Amendment, plaintiff's state-law claims against all *730defendants must be DISMISSED. These may be re-filed in state court." ( Guerrero v. California Department of Corrections and Rehabilitation (N.D.Cal. May 7, 2014, No. C 13-05671 WHA) 2014 WL 1867067, 2014 U.S.Dist. Lexis 63282, citing Pennhurst State School & Hospital v. Halderman (1984) 465 U.S. 89, 106, 104 S.Ct. 900, 79 L.Ed.2d 67.) Following issuance of this order, Guerrero amended his complaint one final time, filing a third amended complaint omitting the state law claims. ( Guerrero I , supra , 119 F.Supp.3d at p. 1069.) As a practical matter, the dismissal of Guerrero's state law claims stripped him of the ability to seek damages in the Federal Action. For monetary relief, he was left with only the equitable remedy of backpay.
Going into trial, Guerrero's third amended complaint presented only federal questions. ( Guerrero I , supra , 119 F.Supp.3d at p. 1069.) In these surviving federal claims, the gist of Guerrero's theory was that "[d]efendants' disqualification of applicants who have previously used an SSN other than their own has an adverse and disparate impact on particular national origin minorities, such as Latinos, who seek to qualify for state employment." Guerrero alleged that the CDCR, with the knowledge and active support of the SPB, was disproportionately disqualifying Latino correctional officer applicants by using question 75 to target formerly undocumented immigrants like himself.
3. Filing of the State Court Action
In accordance with the district court's observation that the state law claims "may be re-filed in state court," Guerrero filed a complaint in San Francisco County Superior Court (State Court Action) while the Federal Action was still pending. Once again, Guerrero named the CDCR and the SPB as defendants along with various individuals, and once again, he alleged failure-to-hire under a disparate impact theory based on the use of question 75. It is undisputed that, factually, the allegations of discrimination in these parallel state and federal proceedings were virtual mirror images.
*1097As a first order of business in the State Court Action, the trial court held a case management conference in which the parties agreed to a stay pending completion of the federal proceedings, but also agreed that, upon resumption of the State Court Action, any collateral estoppel or res judicata issues arising out of the anticipated federal judgment should be decided first. Those issues were then briefed and scheduled for hearing at a time set far enough out on the calendar to trail the entry of judgment in the Federal Action.
4. Trial and Judgment in the Federal Action
While the State Court Action was stayed, a bench trial took place in the Federal Action, which ended with a judgment for Guerrero on his Title VII claim, awarding much of the relief he sought, including reinstatement to the CDCR's correctional officer hiring process and $140,362 in backpay contingent on his successfully completing the CDCR training academy, plus an award of $1,237,024.82 in prevailing party attorney fees and $166,541.87 in costs. ( Guerrero v. California Department of Corrections and Rehabilitation (N.D.Cal. June 16, 2016, No. C 13-05671 WHA) 2016 WL 3360638 at p. 35 ( Guerrero Fees Order ), vacated and remanded, Guerrero II , supra , 701 Fed.Appx. 613.)
Guerrero was not wholly successful in the Federal Action, however. (See Guerrero Fees Order , supra , 2016 WL 3360638, at pp. 35-37.) The district court found for the CDCR on Guerrero's federal equal *731protection claim under section 1983 ( Guerrero I , supra , 119 F.Supp.3d at p. 1082 ), and, while holding that he had suffered discrimination individually, it rejected his claim that the CDCR's use of question 75 is categorically invalid. ( Id. at p. 1081.) The court found that the detection of SSN misuse bears upon the CDCR's legitimate interest in maintaining the "integrity, honesty, and good judgment [of its] corrections officer[s]," and as a result, declined to enjoin its use so long as, going forward, the CDCR properly conformed the question to business necessity criteria established by the Equal Employment Opportunity Commission. ( Ibid. ) The ensuing judgment is now final, having been affirmed on appeal.1 *10985. Dismissal of the State Court Action
Following completion of the Federal Action, the trial court in the State Court Action heard argument on the preclusive effect of the federal judgment. On November 6, 2015, it issued an "Order on Res Judicata Effect of Federal Judgment" ruling that "this case should be dismissed and judgment entered against [Guerrero]" because "[u]nder California law including its primary rights doctrine ... the same primary rights were at issue in the federal case ... and in this case." It is from the adverse judgment entered upon this order that Guerrero now appeals.2
III. DISCUSSION
A. Standard of Review and Principles of Res Judicata
We review a dismissal on grounds of res judicata de novo as an issue of law. ( Noble v. Draper (2008) 160 Cal.App.4th 1, 10, 73 Cal.Rptr.3d 3.) Res judicata-law Latin for "a thing adjudicated"-is an umbrella term encompassing issue preclusion and claim preclusion, both of which describe the preclusive effect of a final judgment. As a general matter under the doctrine of claim preclusion, a final judgment on the merits bars parties or parties in privity from "successive litigation of the very same claim ... as the earlier [action]." ( Taylor v. Sturgell (2008) 553 U.S. 880, 892, 128 S.Ct. 2161, 171 L.Ed.2d 155 ( Taylor ).) The driving principle behind the claim preclusion doctrine is that the parties have had a " 'full and fair opportunity to litigate' " claims alleged in the first action. ( Ibid. , citing Montana v. United States (1979) 440 U.S. 147, 153-154, 99 S.Ct. 970, 59 L.Ed.2d 210.)
Unlike issue preclusion, which applies only to issues that were actually litigated, claim preclusion applies not just to what was litigated, but more broadly to what could have been litigated. Here, under what is sometimes known as the rule against "claim splitting," the doctrines of bar and merger do the work. (See Rest.2d *732Judgments (Second Restatement), § 24.) "Merger" expresses the idea that, for a winning plaintiff, all claims the plaintiff did raise or could have raised merge into the judgment in his favor. (Id . § 18.) If the plaintiff attempts to litigate any of those claims again, the judgment itself serves as a defense. "Bar," on the other hand, refers to the related idea that a judgment for a winning defendant bars the plaintiff from litigating any claims he brought or could have brought in the prior suit. (Id . § 19.) This case involves the merger aspect of claim preclusion. *1099Together, the principles of issue and claim preclusion serve to "relieve parties of the cost and vexation of multiple lawsuits, conserve judicial resources, and, by preventing inconsistent decisions, encourage reliance on adjudication" ( Allen v. McCurry (1980) 449 U.S. 90, 94, 101 S.Ct. 411, 66 L.Ed.2d 308 ), thereby shielding litigants from undue harassment and avoiding the substantial time and expense associated with repetitive litigation. ( Taylor , supra , 553 U.S. at p. 892, 128 S.Ct. 2161.) The reduction of duplicative proceedings also furthers the goals of convenience, efficiency and judicial economy-in one proceeding, the same trial court presides over discovery, motions, and a single trial. ( Allen , supra , 449 U.S. at p. 94, 101 S.Ct. 411.) The rules of claim and issue preclusion protect the integrity of courts by fostering finality and minimizing the potential for conflicting judgments, which serves to promote public confidence in the judicial process. (See Nevada v. United States (1983) 463 U.S. 110, 128-129, 103 S.Ct. 2906, 77 L.Ed.2d 509 ; see also Allan D. Vestal, Res Judicata/Preclusion by Judgment: The Law Applied in Federal Courts (1968) 66 Mich. L.Rev. 1723, 1723.)
B. Applicability of Federal Law
The main issue Guerrero presents on appeal, described by the trial court as "the central problem here," is "which law provides the rule of decision for res judicata analysis." Do we apply California law or federal law?
The basic principles of claim preclusion are roughly the same under California and federal law, but there are some key differences. For example, while federal law defines a "claim" for purposes of claim preclusion using a transactional test, California law uses the older pleading term "cause of action" and defines it according to the common law doctrine of primary rights.3 The more modern transactional approach has been adopted by the Second Restatement. (See id . § 24.) Although recent pronouncements from our high court have moved California law toward alignment with the overall approach to issue and claim preclusion in the Second Restatement, at least in the terminology we employ (see DKN Holdings LLC v. Faerber (2015) 61 Cal.4th 813, 824, 189 Cal.Rptr.3d 809, 352 P.3d 378 ), some features of California claim preclusion law remain distinctive. The primary rights doctrine is one such area. ( Boeken v. Philip Morris USA, Inc. (2010) 48 Cal.4th 788, 804, 108 Cal.Rptr.3d 806, 230 P.3d 342 ; see *1100*733Friedman Prof. Management Co., Inc. v. Norcal Mutual Ins. Co. (2004) 120 Cal.App.4th 17, 27-29, 15 Cal.Rptr.3d 359.)
Guerrero argues that, in determining the preclusive effect of the judgment in the Federal Action, the trial court erroneously applied the California doctrine of primary rights. He correctly points out that in Semtek Int'l Inc. v. Lockheed Martin Corp. (2001) 531 U.S. 497, 121 S.Ct. 1021, 149 L.Ed.2d 32 ( Semtek ), the United States Supreme Court held that federal common law controls the preclusive effect of a federal judgment. The federal judgment in Semtek, to be sure, arose in a diversity case (see 28 U.S.C. § 1332 ), but the language of the opinion in that case is broad. It states that the United States Supreme Court "has the last word on the claim-preclusive effect of all federal judgments." ( Semtek, supra , 531 U.S. at p. 507, 121 S.Ct. 1021, italics omitted.) If there were any doubt about the breadth of this holding, the high court removed it in Taylor, supra, 553 U.S. at page 892, 128 S.Ct. 2161, which applies Semtek in a case where the judgment at issue was entered in a federal question case. (See 28 U.S.C. § 1331 ; Taylor , at p. 891, 128 S.Ct. 2161, citing Semtek , at pp. 507-508, 121 S.Ct. 1021 ; see also Rest.2d Judgments, § 87 ["Federal law determines the effects under the rules of res judicata of a judgment of a federal court"].)
Although federal common law applies under Semtek , the ultimate rule of decision chosen in that case was the law of the state where the judgment-issuing federal court sat, a holding which effectively embeds state law into federal law unless some paramount federal interest calls for a departure from it. This aspect of Semtek is consistent with the conventional approach to conflict of laws in federal diversity cases,4 but leaves open what to do in federal question cases, which present a very different choice-of-law problem.5 While recognizing that " Semtek does not tell us what the rule of decision is when the federal judgment was on a federal question," the trial court went on to apply California law because it perceived no federal interest in the application of federal law. On this point, the court erred. Pockets of federal common law do exist, enunciated case-by-case, independent of state law.6 They are rare, but Taylor quite clearly announces one. "The preclusive effect of a federal-court judgment is determined by federal common law," the high *1101court held in Taylor . At first blush, that might seem like just a straightforward application of Semtek, calling for the application of state law incorporated into federal law, but the Taylor court goes further: "For judgments in federal-question cases[,] ... federal courts participate in developing 'uniform federal rule[s]' of res judicata." ( Taylor, supra , 553 U.S. at p. 891, 128 S.Ct. 2161.)
We read the holding in Taylor as an unequivocal directive that federal claim preclusion law applies in this case, without reference to California law. Long before *734Taylor , many California cases recognized that "[a] federal court judgment has the same effect in the courts of this state as it would in a federal court." ( Martin v. Martin (1970) 2 Cal.3d 752, 761, 87 Cal.Rptr. 526, 470 P.2d 662 ; see also Younger v. Jensen (1980) 26 Cal.3d 397, 411, 161 Cal.Rptr. 905, 605 P.2d 813 ; Levy v. Cohen (1977) 19 Cal.3d 165, 173, 137 Cal.Rptr. 162, 561 P.2d 252 ; Nathanson v. Hecker (2002) 99 Cal.App.4th 1158, 1163, 121 Cal.Rptr.2d 773 ; Butcher v. Truck Ins. Exchange (2000) 77 Cal.App.4th 1442, 1452, 92 Cal.Rptr.2d 521 ; Merry v. Coast Community College Dist. (1979) 97 Cal.App.3d 214, 222-223, 158 Cal.Rptr. 603.) These cases now seem prescient. The CDCR reads them narrowly, arguing that federal law is relevant only to the extent consistent with California law, a notion taken from dicta in a footnote in a case that did not involve the preclusive effect of a federal judgment.7 The argument is creative, and might have been plausible before 2008, but giving federal law such a subordinate role in the face of the high court's holding in Taylor strikes us as inconsistent with the supremacy clause. ( U.S. Const., art. VI, cl. 2.)
Citing City of Simi Valley v. Superior Court (2003) 111 Cal.App.4th 1077, 4 Cal.Rptr.3d 468 and several other cases which rely on California claim preclusion law,8 the CDCR insists it has long been settled that when an action "is filed in state court and the defendants claim the suit is barred by a final federal judgment, California will determine the res judicata effect of the prior federal court judgment on the basis of whether the federal and state actions *1102involve the same primary right." The CDCR also claims, without authority, that "[f]ederal law does not, and should not, govern the preclusion of state claims in state court against a state entity defendant." But none of the cases the CDCR relies upon as declarative of settled law addresses Semtek, either on its own terms or in light of Taylor . Guerrero criticizes the approach to federal-state choice-of-law issues in these cases as "haphazard." We would not put it that baldly since the ground has shifted in this area, and it often does not matter whether federal or state law applies in any event. But whatever explains the lack of precise attention to choice-of-law in the Simi Valley line of cases, we believe they fail to capture the high court's latest guidance.
The only California case we have found that takes account of the changed landscape following Semtek , correctly stating the rule announced in Taylor -oddly, without citing it, even though Taylor had been on the books by then for more than a year-holds that "where a prior federal judgment was based on federal question jurisdiction, the preclusive effect *735of the prior judgment of a federal court is determined by federal law." ( Louie v. BFS Retail & Commercial Operations, LLC (2009) 178 Cal.App.4th 1544, 1553, 101 Cal.Rptr.3d 441, italics added ( Louie ).) We think Louie was right.9 "Where a federal court, in a case brought under [federal] and state ... laws, does not resolve any *1103issue of the state ... laws, the federal courts will dismiss the state claims without prejudice to their being filed in state court, even where the state ... statutes incorporate the [federal law]." ( Louie, at p. 1555, 101 Cal.Rptr.3d 441.) That was the case in Louie , which involved claims brought under the federal Americans with Disabilities Act (ADA) and its California statutory counterpart. The federal consent decree there-which was, of course, a final judgment-barred injunctive and declaratory relief based on ADA violations, but expressly carved out damages claims based on state law. ( Louie , at pp. 1557-1558, 101 Cal.Rptr.3d 441.) Applying federal claim preclusion law, while recognizing that state law called for the same result ( id . at p. 1554, 101 Cal.Rptr.3d 441 ["we look to the preclusive effect under federal law, though we observe federal law is consistent with California law in this case"] ), the court held that state law claims for damages remained available in a state action despite the consent decree. ( Id. at p. 1558, 101 Cal.Rptr.3d 441.) The same analysis applies here.
C. Jurisdictional Competency Exception
We agree with Guerrero that the trial court erred in applying California's *736primary rights doctrine, but that doctrine alone does not explain the court's ruling here. Rather, the court appears to have proceeded on the understanding that federal law recognizes an exception to claim preclusion that "salvages" Guerrero's state claims for damages in these circumstances, while California law does not. This, in our view, sets up a false conflict. Under section 26(1)(c) of the Second Restatement, claim preclusion does not apply where "[t]he plaintiff was unable to rely on a certain theory of the case or to seek a certain remedy or form of relief in the first action because of the limitations on the subject matter jurisdiction of the courts ... and the plaintiff desires in the second action to rely on that theory or to seek that remedy or form of relief." (See Marrese v. American Academy of Ortho. Surgeons (1985) 470 U.S. 373, 382, 105 S.Ct. 1327, 84 L.Ed.2d 274.)10 There is no denying that the basis for the dismissal of Guerrero's state law claims for damages in the Federal Action, the Eleventh Amendment-which is jurisdictionally disabling in an Article III court, absent a waiver-was a limitation on "the subject matter jurisdiction" of the district *1104court.11 Contrary to what the trial court appears to have believed, this exception has been recognized in both federal law and California law.12 Thus, claim preclusion does not apply here under either federal or California law.
Faced with a well-established claim preclusion exception, the CDCR attempts to offer a trump card. According to the CDCR, under Acuña v. Regents of University of California (1997) 56 Cal.App.4th 639, 65 Cal.Rptr.2d 388 ( Acuña ) there is, in effect, an exception to the *737exception. Even where a plaintiff suffers the dismissal of state law claims in federal court under the Eleventh Amendment, the CDCR argues, Acuña holds that claim preclusion forecloses the pursuit of those claims in state court if, upon the federal court's prior dismissal, the plaintiff elects to continue pursuing federal claims in federal court, and then takes the surviving claims to judgment, rather than voluntarily dismissing everything and re-filing all claims in state court. The trial court found Acuña to be "on point" and followed it, observing that plaintiff Acuña's state law claims were "dismissed on 11th Amendment grounds, just as here." This, too, was error.
To unravel the problem, we must start with Mattson v. City of Costa Mesa (1980) 106 Cal.App.3d 441, 164 Cal.Rptr. 913 ( Mattson ), on which Acuña relied. In that case, the plaintiff brought a federal action asserting federal civil rights claims, invoking federal question jurisdiction, together with state law tort claims based on what was once known as pendent federal jurisdiction. ( Mattson, at p. 444, 164 Cal.Rptr. 913.)13 The federal court dismissed the state law claims, and *1105proceeded to try the federal claims, which resulted in a judgment for the defense. ( Mattson, at p. 445, 164 Cal.Rptr. 913.) While the federal action was still pending, but before entry of judgment, the state court dismissed the revived state claims on grounds of res judicata. ( Ibid. ) On appeal, the Court of Appeal affirmed under California claim preclusion law, interpreted in light of the Restatement First of Judgments (First Restatement), section 62 and the Fifth Tentative Draft of the Second Restatement (Tent. Draft. No. 5), sections 61 and 61.1. ( Mattson , at pp. 448-450, 452-454, 164 Cal.Rptr. 913.)14
The Mattson court described the circumstance presented there as one where the federal court "in the first action has discretionary jurisdiction and declines to exercise [it]." ( Mattson , supra , 106 Cal.App.3d at p. 451, 164 Cal.Rptr. 913.) That situation, the court said, is what may be described as the "state court-federal court pendent-jurisdiction problem." ( Ibid. ) While the First Restatement did not specifically deal with the issue, the court explained that "[s]ome effort has been made by the authors of the Restatement Second of Judgments, Fifth Tentative Draft, to deal with [it]." ( Mattson, at p. 452, 164 Cal.Rptr. 913.) After summarizing in detail pertinent Restatement principles-drawing primarily from comment j to the First Restatement, section 62, as carried forward in comment g, section 61 of the Second Restatement (Tent. Draft No. 5)-the court observed that, generally, a "plaintiff, having voluntarily brought his action in a court which can grant him only limited relief, cannot insist upon maintaining another action on the claim." ( Mattson, at pp. 448, 452, 164 Cal.Rptr. 913.)
But Mattson must be read closely. The court was careful not to attach preclusive consequences to the mere act of filing *738state claims in federal court, for that would have had a "chilling effect" on plaintiffs' ability to take related federal claims into a federal forum. ( Mattson , supra , 106 Cal.App.3d at p. 454, 164 Cal.Rptr. 913.) Rather, the heart of the court's rationale was this: "The initial choice by the plaintiff to file suit in federal court will not necessarily result in splitting his cause of action, because the federal court may well exercise pendent jurisdiction over the nonfederal claim. However, when the federal court has been requested to and has declined to exercise pendent jurisdiction over the nonfederal claim, the plaintiff is presented with a new choice . He may proceed to trial on the federal claim or, usually, he may elect to dismiss the federal claim without prejudice [citations]. Once it is known that the federal court will not exercise pendent jurisdiction over the state claim, *1106plaintiff's proceeding to trial in the federal court on the federal claim alone will necessarily result in splitting the plaintiff's cause of action, and that fact should be apparent to the plaintiff." ( Id. at pp. 454-455, 164 Cal.Rptr. 913, italics added.)
"In such circumstances," the Mattson court explained, "the rule that would best accommodate the rights of the plaintiff to fully litigate his claim and to invoke the jurisdiction of the federal court and the right of the defendant, the courts and the public to be free of multiple litigation of the same cause of action, is that once the federal court has declined to exercise pendent jurisdiction over the state claim, if the plaintiff then elects to proceed to trial and judgment in the federal court, his entire cause of action is either merged in or barred by the federal court judgment so that he may not thereafter maintain a second suit on the same cause of action in a state court. [¶] A contrary rule would invite manipulation. It would permit a plaintiff halfheartedly to request the federal court to exercise pendent jurisdiction, offer little resistance to any argument by the defendant against its exercise, and hope that the federal court would decline to exercise pendent jurisdiction and thereby reserve to the plaintiff a second chance to prevail in a state court action should he be successful in the federal court." ( Mattson , supra , 106 Cal.App.3d at p. 455, 164 Cal.Rptr. 913.)
Acuña extended the Mattson rule to a case where the plaintiff landed in federal court by removal, not by choice. The case began with a state court action asserting employment discrimination claims under the federal Age Discrimination in Employment Act (ADEA) and for race, ethnicity and age bias under FEHA. ( Acuña , supra , 56 Cal.App.4th at pp. 643-644, 65 Cal.Rptr.2d 388.) One of the defendants, the University of California, removed the action to federal court and brought a motion to dismiss on Eleventh Amendment grounds. ( Acuña, at p. 644, 65 Cal.Rptr.2d 388.) The plaintiff responded with his own motion to remand the FEHA claims to state court. ( Acuña, at p. 644, 65 Cal.Rptr.2d 388.) The motion to remand was granted (not the motion to dismiss) ( ibid. ), and the federal case proceeded to trial on the ADEA claim, which resulted in a plaintiff's judgment. ( Acuña, at p. 644, 65 Cal.Rptr.2d 388.) Seeking additional relief (punitive damages were not available on the ADEA claim), the plaintiff attempted to pursue his FEHA claims on remand in state court, but the court granted summary adjudication against him on res judicata grounds. ( Acuña, at pp. 644-645, 65 Cal.Rptr.2d 388.) Applying California law, the court held the federal and state claims were based on the same primary right-" 'the right to be free from employment discrimination' "-and that they were merged into the federal judgment and therefore foreclosed. ( Id . at p. 649, 65 Cal.Rptr.2d 388.)
*739We are not persuaded that Acuña is controlling. First of all, it is not clear to us that, as the Mattson court put the matter, the federal court in Acuña was *1107requested to and declined to exercise its discretionary supplemental jurisdiction over state law claims. ( Mattson , supra , 106 Cal.App.3d at p. 451, 164 Cal.Rptr. 913.) Plaintiff Acuña's state law claims were dismissed on his own motion, presumably under rule 41(a) of the Federal Rules of Civil Procedure (28 U.S.C.), application for voluntary dismissal. Thus, he split his claims by choice, not under compulsion of a federal court's determination that it had no power to hear them.15 Had there been an Eleventh Amendment dismissal, it would have triggered section 26(1)(c) of the Second Restatement (§ 61.2(1)(c) of Tent. Draft No. 5), a claim preclusion exception neither Mattson nor Acuña cites or discusses. Because the dismissal in Acuña was based on the plaintiff's considered election to dismiss only some of his claims in federal court, the case falls comfortably within the Mattson rule. That is not the situation we have here. Guerrero's claims were dismissed on Eleventh Amendment grounds, which was not a discretionary disposition. If there was a tactical choice on this record, it was exercised by the CDCR-to waive Eleventh Amendment immunity, or to face claims for damages in a separate action in state court.
What must ultimately carry the day, however, no matter how Acuña is read, is that it predates Semtek and Taylor . Mattson , on which Acuña relies, has been both praised (see Hernandez v. City of Pomona (2009) 46 Cal.4th 501, 525, 94 Cal.Rptr.3d 1, 207 P.3d 506 (conc. opn. of Corrigan, J.) ["[t]he Mattson court carefully considered the applicable Restatement principles, and its reasoning was sound"] ) and criticized (see Harris , supra , 104 Cal.App.4th at pp. 188-189, 127 Cal.Rptr.2d 791 [declining to follow "two-decade old" Mattson rule as outdated in light of case law adopting a more recent, "widely endorsed pronouncement of the law" as reflected in the Second Restatement].) We are inclined to think Harris was correct about Mattson , albeit for somewhat different reasons,16 but that *740is not the dispositive point here. Just as in Louie , "we look to the preclusive effect [of the judgment in the Federal Action] *1108under federal law" ( Louie , supra , 178 Cal.App.4th at p. 1559, 101 Cal.Rptr.3d 441 ), and find it dispositive that neither Mattson nor Acuña has any foundation in federal law. Accordingly, we conclude that Guerrero is free to pursue his state claims for damages in superior court. We take no view on the extent to which, if at all, relitigation of issues implicated by those claims may be necessary. The trial court should now proceed to make that determination after applying the doctrine of issue preclusion
IV. DISPOSITION
The judgment dismissing Guerrero's state claims is reversed and remanded for further proceedings consistent with this opinion.
We concur:
Tucher, J.
Lee, J.*