STJ & Arbitration · Q2 2026
STJ & Arbitration Bulletin
Second Quarter of 2026
Advocacia Adriano Dib
STJ & Arbitration
Second Quarter 2026 Decisions — April through June
This quarter, the STJ delivered a consistent message: arbitration agreements in Brazil hold, and courts will not second-guess them simply because performance has become inconvenient.
The Court rebuffed a series of attempts to litigate around valid arbitration clauses. Financial distress, insolvency proceedings, prohibitive costs — none of these, the STJ confirmed, justify bypassing the agreed forum. Under the Kompetenz-Kompetenz principle, those arguments go to the arbitrator first. And even where enforcement is judicial, the merits of the underlying contract stay off the table: a party that wants to contest the deal must do it in arbitration, not in opposition to enforcement proceedings.
That said, courts retain a narrow but meaningful role before the tribunal is constituted. Pre-award evidence collection and document production that stop short of the merits remain available in court — at least until arbitration is underway. After that, the court steps aside. The arbitration clause also has its limits: it does not bind non-signatories, and it does not travel to instruments that never included one.
On annulment, the STJ held its deferential line. Parties that participated fully in the proceedings and failed to raise timely objections were found to have forfeited their complaints — an estoppel principle that common law practitioners will recognize readily. The ninety-day clock for challenging an award runs regardless of the procedural vehicle chosen.
Internationally, the Special Panel maintained a strict separation between recognition and the merits, granting enforcement while keeping substantive challenges firmly outside the door. The quarter’s most significant doctrinal development, however, is in Section V: three decisions, each going the same way, establishing that a subrogated insurer steps into the policyholder’s arbitration clause along with the claim. That closes a split flagged in Q1. The one live fault line sits in Section VI — where a divided court allowed labor proceedings to suspend arbitration pending a threshold determination on employment status. That ruling deserves watching.
Thematic Overview
IForce of the Arbitration Clause & Kompetenz-Kompetenz
IIState Court Jurisdiction Alongside Arbitration
IIIJudicial Review of Arbitral Awards
IVForeign Arbitral Awards & Recognition
VSubrogated Insurers & the Arbitration Clause
VIArbitration, Government Entities & Labor Courts
VIIStandard-Form Contracts, Consumer Law & Lease
·21 decisions — April through June 2026
Table of Contents
IForce of the Arbitration Clause and Kompetenz-Kompetenz5 decisions
IIState Court Jurisdiction Alongside Arbitration3 decisions
IIIJudicial Review of Arbitral Awards4 decisions
IVForeign Arbitral Awards and Recognition3 decisions
VSubrogated Insurers and the Arbitration Clause3 decisions
VIArbitration, Government Entities and Labor Courts2 decisions
VIIStandard-Form Contracts, Consumer Law and Lease Agreements1 decision
1
Section 1
Force of the Arbitration Clause and Kompetenz-Kompetenz
1
Case 1
AREsp 2,747,092/RJ
STJ, 4th Panel · June 15, 2026 · DJe June 18, 2026
Judicial reorganization
Facts
A company in judicial reorganization tried to escape its arbitration clause on two grounds: the originally designated institution (CIMA) had dissolved, and the cost of arbitration was prohibitive given its financial situation.
Ruling
Neither argument works at the court level. A dissolved institution voids the administered-arbitration arrangement, not the clause itself. Financial distress and cost objections belong to the arbitrator — not the courts — under Kompetenz-Kompetenz. The STJ dismissed the action.
Practical Takeaway
Brazilian courts will not rescue a party from its arbitration clause because the administrator shut down or proceedings got expensive. Take those arguments to the tribunal.
Case 2
AgInt no AREsp 2,870,413/GO
STJ, 4th Panel · June 8, 2026 · DJe June 12, 2026
Financial hardship
Facts
A franchisee sued in state court for a declaration of contractual nullity, claiming it could no longer afford arbitration under the franchise agreement.
Ruling
Not the courts’ call. The STJ reaffirmed that supervening financial incapacity does not invalidate a valid arbitration clause. The franchisee’s argument had to go to the arbitrator first. This tracks AREsp 2,747,092/RJ decided the same quarter.
Practical Takeaway
“I can’t afford it” is not a judicial exit from arbitration. The STJ is drawing a firm line: financial hardship arguments belong in front of the arbitrator, not the courts.
Case 3
EDcl no REsp 1,978,973/AP
STJ, 4th Panel · June 1, 2026 · DJe June 8, 2026
Underlying consideration of bill of exchange
Facts
A party filed a declaratory action to have a bill of exchange declared unenforceable, framing the challenge as “formal” rather than substantive — and therefore, it argued, within the state court’s reach even though the underlying contract was subject to arbitration.
Ruling
The STJ rejected the framing. Whether a bill of exchange has valid underlying consideration is a question about the contractual merits — exactly what the arbitration clause covers. Courts dismissed. Motions for clarification rejected.
Practical Takeaway
You cannot route a merits dispute to state court by labeling it a formal defect. If the question is whether a debt exists under an arbitrable contract, it goes to the arbitrator.
Case 4
REsp 2,178,118/SC
STJ, 4th Panel · May 25, 2026 · DJe May 28, 2026
Opposition to enforcement
Facts
Respondents in enforcement proceedings on a mortgage deed tried to contest the underlying contractual obligations through opposition filings, adding procedural arguments about preclusion and the scope of dismissal.
Ruling
No. State courts can process enforcement, but they cannot look behind a title linked to an arbitration clause to examine the merits of the underlying contract. The respondents needed to open arbitration to contest the debt — and seek a stay there if appropriate.
Practical Takeaway
Enforcement and arbitration can coexist — but each in its own lane. Substantive contract disputes belong in arbitration. Opposition to enforcement is not the back door.
Case 5
AgInt no AgInt no REsp 2,110,634/GO
STJ, 4th Panel · May 25, 2026 · DJe May 28, 2026
Ineffective clause in standard-form contract
Facts
Respondents in enforcement proceedings tried to stay execution by invoking an arbitration clause in a standard-form contract, without showing they had affirmatively assented to it.
Ruling
Two hurdles, two failures. A clause in a standard-form contract requires explicit assent — bold text, a separate document, or a specific initial. Without that, the clause is unenforceable. And even a valid clause does not stay judicial enforcement on its own; the party must go to the tribunal and show a genuine link between the arbitration and the title.
Practical Takeaway
Don’t assume a boilerplate arbitration clause will stick in an adhesion contract — or that it will stop enforcement proceedings even if it does.
2
Section 2
State Court Jurisdiction Alongside Arbitration
2
Case 6
REsp 2,161,191/RJ
STJ, 3rd Panel · June 8, 2026 · DJe June 11, 2026
Pre-arbitration evidence gathering
Facts
In the context of a hydroelectric project, one party sought to collect witness testimony before arbitration on a Memorandum of Understanding that contained no arbitration clause and selected a judicial forum. The theory: related contracts with arbitration clauses should pull everything into the arbitral tribunal’s jurisdiction.
Ruling
The STJ disagreed. Arbitral jurisdiction does not expand to instruments without a clause or to non-signatories — not even when those instruments sit alongside arbitrable contracts in the same project. The case was distinguished from REsp 2,023,615/SP, where the evidence was grounded in arbitrable contracts between signatories.
Practical Takeaway
Clause extension doesn’t work by proximity. Each instrument stands on its own terms. If the MoU points to court, that’s where pre-arbitration evidence gathering for the MoU belongs.
Case 7
REsp 2,219,466/RS
STJ, 4th Panel · April 24, 2026 · DJe May 7, 2026
Document disclosure
Facts
A shareholder sought document disclosure on company assets and equity appraisal before commencing arbitration. The other party invoked the shareholders’ agreement’s arbitration clause to get the case dismissed.
Ruling
Courts can handle this. Mandatory document production that doesn’t touch the contractual merits is explicitly authorized before arbitration under Article 22-A of the Arbitration Act. Read alongside EDcl no REsp 1,978,973/AP — which kept merits disputes in arbitration — this ruling draws the line cleanly: instrumental measures go to court; the underlying dispute goes to the arbitrator.
Practical Takeaway
Pre-arbitration document disclosure stays in court — it’s instrumental, not substantive. The distinction is simple: evidence gathering and conservatory measures before the tribunal is constituted belong in court. Who owes what under the contract belongs in arbitration.
Case 8
AgInt na Rcl 50,418/AP
STJ, 2nd Section · May 13, 2026 · DJe May 18, 2026
Pre-arbitration injunction and lapse
Facts
A pre-2015 STJ order had kept a preliminary injunction alive until arbitration was “effectively commenced.” A follow-on petition contested whether that threshold had been reached.
Ruling
It had. Arbitration commenced on March 7, 2025, when the arbitrator accepted appointment. An earlier ruling had already capped the injunction’s life at thirty days post-commencement — consistent with Article 22-A of the Arbitration Act and Article 308 of the Code of Civil Procedure. Once arbitration starts, the court steps aside.
Practical Takeaway
Pre-arbitration court orders expire when the tribunal is constituted. After that, it’s the arbitrator’s call whether to maintain, modify, or lift any protective measure. Parties that keep state court relief running past that point encroach on arbitral jurisdiction.
3
Section 3
Judicial Review of Arbitral Awards
3
Case 9
REsp 2,195,061/SP
STJ, 3rd Panel · May 5, 2026 · DJe May 22, 2026 (Writing Justice: Min. Ricardo Villas Boâs Cueva)
Supervening fact in ICC arbitration
Facts
An ICC tribunal ruled on the early termination of contracts — a development that post-dated the Terms of Reference. The losing parties challenged the award, arguing the tribunal had ruled beyond the scope of the arbitration agreement.
Ruling
Majority rejected the challenge. ICC rules allow the Terms of Reference to be amended, and the parties engaged fully on the new issue without objecting in real time. Active participation foreclosed the later nullity claim. The Court applied the venire contra factum proprium principle: you cannot litigate an issue vigorously and then claim the tribunal had no authority to decide it. Jurisdictional objections must come at the first opportunity under Article 20 of the Arbitration Act.
Practical Takeaway
Object early or lose the argument. A party that actively litigates a contested issue in the arbitration cannot turn around and claim the tribunal lacked jurisdiction. The Terms of Reference are not a straitjacket — and belated scope challenges don’t survive estoppel.
Case 10
REsp 2,212,083/SP + EDcl
STJ, 3rd Panel · March 18, 2026 (REsp); May 4, 2026 (EDcl)
90-day limitation period
Facts
A respondent in enforcement proceedings tried to raise nullity grounds against the arbitral award, arguing the ninety-day limitation period under Article 33(1) of the Arbitration Act didn’t apply when the challenge came through enforcement opposition rather than a standalone annulment action.
Ruling
It does. The ninety-day clock runs from notification of the award — partial or final — regardless of how the party frames the challenge. Once it expires, Article 32 grounds are gone. In enforcement opposition, only the narrower grounds under Article 525(1) of the Code of Civil Procedure remain.
Practical Takeaway
There is no procedural workaround to the ninety-day limitation. Miss it on an annulment action and you’ve missed it in enforcement opposition too. One more detail: partial awards trigger the clock independently — don’t wait for the final award to start counting.
Case 11
REsp 2,210,332/SC
STJ, 3rd Panel · April 7, 2026 · DJe April 14, 2026
Timeliness of the arbitral award
Facts
A party sought to annul an award on the ground that it had been issued outside the ten-day window after the arbitrator was notified. The award was signed and filed on March 12–13, 2015; the parties received formal notification on March 17.
Ruling
Timely. The deadline is satisfied when the award is signed and submitted — not when parties receive it. No prejudice was shown. The Third Panel rejected the formalistic reading.
Practical Takeaway
Technical timing attacks on awards face a high bar. The period under Article 12(III) of the Arbitration Act runs from notification of the arbitrator, not notification of the parties. Without demonstrated prejudice, a formal irregularity does not become a nullity.
Case 12
REsp 2,259,356/GO
STJ, 4th Panel · May 25, 2026 · DJe May 28, 2026
Confirmatory award and repossession
Facts
A creditor sought repossession under a confirmatory arbitral award after the debtor defaulted again on a condition the parties had expressly built into the settlement. The debtor argued a confirmatory award couldn’t support an eviction.
Ruling
Wrong. An arbitral award — confirmatory or not — is a fully enforceable judicial title under Article 515(VII) of the Code of Civil Procedure and Articles 18 and 31 of the Arbitration Act. An express resolutory condition requires no further notice before it takes effect. The lower court’s requirement for an appraisal of improvements was preserved, but enforcement otherwise proceeded.
Practical Takeaway
Arbitral awards confirming settlements are fully enforceable. If the parties agreed that default triggers automatic resolution, that’s what they get. Courts will not graft new procedural steps onto a deal already negotiated in arbitration.
4
Section 4
Foreign Arbitral Awards and Recognition
4
Case 13
HDE 10,022/EX
STJ, Special Panel · June 3, 2026 · DJe June 11, 2026
No assets in Brazil
Facts
A Chinese company sought to block recognition of an LCIA award by arguing there were no Brazilian assets to execute against and that the claim was time-barred under Brazilian law.
Ruling
Neither defense belongs at the recognition stage. Recognition proceedings check the form, not the merits. Whether there are assets to go after is an execution question, raised after recognition is granted. The Special Panel recognized the award.
Practical Takeaway
Recognition and enforcement are separate steps. A debtor with no assets in Brazil still faces a recognizable award — and once recognized, enforcement can follow assets wherever they appear. Merits and patrimonial objections stay out of the recognition proceeding.
Case 14
HDE 8,855/EX
STJ, Special Panel · May 20, 2026 · DJe May 26, 2026
Change of arbitral institution
Facts
A recognition petition came in for an award issued by a Portuguese arbitral institution — but the arbitration clause had designated the CAM-CCBC. The substitution appeared only in a notarial document, unsigned by both parties.
Ruling
Recognition denied. The institution that issued the award must be demonstrably competent under the agreement. Changing institutions requires the same formality as the original clause. A unilateral notarial document doesn’t satisfy that standard.
Practical Takeaway
If you change arbitral institutions, get it in writing — signed by everyone. An informal substitution can sink the entire award at the recognition stage.
Case 15
AgInt nos EDcl na HDE 7,870/EX
STJ, Special Panel · May 12, 2026 · DJe May 15, 2026
Due process and limits of recognition proceedings
Facts
The respondent in recognition proceedings claimed it had never been notified of the arbitrator’s appointment or the proceedings, and that pre-hearing preparation time was inadequate. It sought denial of recognition under Article 38(III) of the Arbitration Act.
Ruling
The record showed service of process and counsel at the hearing. That was enough. The STJ held that evaluating the adequacy of preparation time would exceed the scope of recognition proceedings.
Practical Takeaway
Due process challenges to recognition require proving a total absence of opportunity to be heard — not just a bumpy ride procedurally. Representation by counsel at the hearing is strong evidence against a denial-of-notice claim.
5
Section 5
Subrogated Insurers and the Arbitration Clause
5
Case 16
REsp 2,106,052/RJ
STJ, 3rd Panel · April 13, 2026 · DJe April 16, 2026
Subrogation in transport contract
Facts
Insurance companies filed subrogation claims against an international maritime carrier after paying out insured losses. The lower court held the arbitration clause inapplicable to the insurer, reasoning that subrogation transfers the credit but not the procedural terms.
Ruling
The STJ reversed. Legal subrogation under Articles 349 and 786 of the Civil Code puts the subrogee in the subrogor’s full legal position — rights, claims, and the agreed dispute resolution mechanism. Letting the insurer pick up the claim while dropping the clause would be an unwarranted windfall. Dismissal reinstated.
Practical Takeaway
Subrogation carries the arbitration clause. This ruling signals a convergence between the Third and Fourth Panels on the point, closing a split flagged in Q1 2026. Insurers pursuing subrogation claims should plan for arbitration when the underlying contract requires it.
Case 17
AgInt no AREsp 2,879,723/RJ
STJ, 3rd Panel · May 25, 2026 · DJe May 28, 2026
Subrogation and equipment damage
Facts
An insurer filed a subrogation claim for generator damage, seeking reimbursement for amounts paid to the insured. The defendants invoked the arbitration clause in the equipment supply contract. The insurer argued it had never consented to arbitration and invoked Article 786(2) of the Civil Code.
Ruling
Neither defense worked. Article 786 subrogation passes the clause along with the claim. Article 786(2) — which protects the insurer from acts by the insured that diminish its rights — doesn’t apply to a clause the insured agreed to before the policy was issued. And STJ Precedent 1,282, which limits adhesion protections in forum selection, doesn’t govern arbitration agreements.
Practical Takeaway
An insurer that underwrites a contract with an arbitration clause is bound to it upon subrogation. Article 786(2) is not an escape hatch for pre-existing clauses. And Precedent 1,282 stays in its lane — it governs forum selection, not arbitration.
Case 18
AgInt no REsp 2,236,188/SC
STJ, 3rd Panel · May 18, 2026 · DJe May 21, 2026
Subrogation + foreign forum
Facts
An insurer brought a subrogation claim for fertilizer shipment losses against a maritime carrier, despite the transport contract designating the Oslo Tribunal and Norwegian law. The insurer argued subrogation doesn’t reach procedural clauses.
Ruling
It does. The STJ applied the same logic from Cases 16 and 17: subrogation transfers both the claim and the agreed dispute resolution forum. Consumer law and Precedent 1,282 don’t apply to arm’s-length commercial contracts between sophisticated parties. Case dismissed for lack of Brazilian jurisdiction.
Practical Takeaway
Three consecutive Third Panel rulings, same result. For international commercial contracts, an insurer that steps into the insured’s shoes also steps into its dispute resolution obligations — including a foreign arbitral forum.
6
Section 6
Arbitration, Government Entities and Labor Courts
6
Case 19
REsp 2,223,325/RJ
STJ, 1st Panel · May 19, 2026 · DJe June 2, 2026
Government payment order and retained private funds
Facts
An arbitral award recognized a creditor’s right to success fees held in a municipal public lighting fund — money originally deposited by the project’s winning bidder. In enforcement, the municipality argued the award triggered the precatório regime for government payments.
Ruling
It didn’t. The precatório regime applies when an award creates a payment obligation out of public funds. Here the municipality was holding private funds in custody — it was ordered to pass them along, not to pay a debt from its own budget.
Practical Takeaway
Not every arbitral award against a public entity goes into the precatório queue. The key distinction: was the entity ordered to pay from public funds, or to release private funds it was holding? The latter doesn’t qualify. The STJ will not let the government use the precatório framework as a delay mechanism.
Case 20
CC 210,510/SP
STJ, 2nd Section · May 7, 2026 · DJe May 28, 2026
Employment status as threshold issue
Facts
A company commenced arbitration for breach of a non-compete and confidentiality agreement. The service provider responded by filing a labor claim in state court, alleging the contract masked an employment relationship. The Second Section had to decide who goes first.
Ruling
The Labor Court does — by majority. The threshold question of whether an employment relationship exists belongs to the labor judiciary before arbitration may proceed. The arbitration was stayed. Justice Gallotti dissented, urging Kompetenz-Kompetenz and pointing to STF Precedent 1,389 (on fraud in civil contracts) as a pending variable.
Practical Takeaway
A decision worth watching. According to the majority, a labor claim is enough to pause arbitration pending judicial determination of the nature of the relationship. The dissenting votes reveal a tension that remains unresolved within the STJ itself.
7
Section 7
Standard-Form Contracts, Consumer Law and Lease Agreements
7
Case 21
AREsp 3,161,519/SP
STJ, 4th Panel · May 18, 2026 · DJe May 22, 2026
Digital lease and standard-form contract
Facts
Lessees challenged an arbitration clause in a lease agreement signed through a digital platform on three grounds: the clause lacked the formalities required by Article 4(2) of the Arbitration Act; the relationship was consumer-facing; and their decision to file in court showed they had rejected arbitration.
Ruling
All three failed. The lower court found the clause was bolded, underlined, and separately initialed — satisfying Article 4(2). Those findings couldn’t be relitigated in the STJ. Landlord-tenant relationships don’t create consumer relationships under Brazilian law. And filing in court is not a valid opt-out from a valid arbitration clause.
Practical Takeaway
A digitally executed lease can validly include an arbitration clause — the medium doesn’t change the formal requirements. Landlord-tenant is not a consumer relationship, so consumer-law protections against adhesion arbitration clauses don’t apply.