AttornmentAttornment is a jurisdictional concept. One speaks of someone 'attorning' to the jurisdiction of a tribunal (the term as used here includes a court), typically the tribunal's geographical jurisdiction, by continuing to participate in the procedure of the tribunal after commencement of an action.
. Sakab Saudi Holding Company v. Al Jabri
In Sakab Saudi Holding Company v. Al Jabri (Ont CA, 2021) the Court of Appeal considered a stay pending appeal motion, which is heard on the same principles as an interlocutory injunction. The appeal was of an order below that held that Ontario courts had jurisdiction to heard a lawsuit between a Saudi-based enterprise, and the court below had ordered that the present moving party respond to a Mareva injunction application below. The issue of attornment thus arose, which the Court of Appeal considered at the irreparable harm stage of the stay test [paras 23-36].
. C.C. v. J.B.
In C.C. v. J.B. (Ont CA, 2021) the Court of Appeal stated the basics of attornment:
 The mother brought no motion challenging jurisdiction under r. 16(12) of the Family Law Rules, O. Reg. 114/99. Instead, she took steps in and argued the merits of the underlying motions. She therefore attorned to the court’s jurisdiction by “[taking] steps beyond merely contesting the jurisdiction of [the] court”: Lilydale Cooperative Limited v. Meyn Canada Inc., 2019 ONCA 761, 439 D.L.R. (4th) 385, at para. 52; Kunuthur v. Govindareddigari, 2018 ONCA 730, 427 D.L.R. (4th) 120, at para. 18, leave to appeal refused,  S.C.C.A. No. 449.. UD Trading Group Holding PTE. Limited v. TransAsia Private Capital Limited
In UD Trading Group Holding PTE. Limited v. TransAsia Private Capital Limited (Ont CA, 2021) the Court of Appeal considered an attornment issue:
 Nor does the responding parties’ decision to bring a security for costs motion in this appeal assist the moving parties. Attornment occurs where a party takes steps suggesting they have accepted jurisdiction, which typically are “steps to defend the merits of a proceeding”: Gerard J. Kennedy, “Jurisdiction Motions and Access to Justice: An Ontario Tale” (2018) 55 Osgoode Hall L.J. 79, at p. 103. Attornment does not occur where a party merely contests the jurisdiction of the court: Lilydale Cooperative Ltd. v. Meyn Canada Inc., 2019 ONCA 761, 439 D.L.R. (4th) 385, at para. 52. Nor does it occur where a party takes procedural steps that deal solely with the procedural mechanics of the jurisdiction hearing: Fraser v. 4358376 Canada Inc., 2014 ONCA 553, 324 O.A.C. 68, at para. 15.. Trindade v. Jantzi
In Trindade v. Jantzi (Div Ct, 2021) the Divisional Court clarifies that 'attornment' is an aspect of international law, not local (within Ontario law):
 The Board made no error in finding that the respondents did not “attorn” to the Superior Court’s jurisdiction. Attornment is a concept that arises in the context of private international law. Counsel for the appellant was not able to identify any case law that supported his argument that the respondents’ participation in the Superior Court application was a form of attornment. Nothing further needs to be said about this issue.. Kunuthur v. Govindareddigari
In Kunuthur v. Govindareddigari (Ont CA, 2018) the Court of Appeal succinctly states the essence of attornment:
(ii) Attornment. Bye Estate v. Adair
 A party attorns to a court’s jurisdiction when it goes beyond simply challenging the jurisdiction of that court and, instead, litigates a claim on the merits: see Van Damme v. Gelber, 2013 ONCA 388 (CanLII), 115 O.R. (3d) 470, at paras. 3, 24, leave to appeal refused,  S.C.C.A. No. 342; and Wolfe v. Wyeth, 2011 ONCA 347 (CanLII), 282 O.A.C. 64, at para. 44.
In Bye Estate v. Adair (Div Ct, 2020) the Divisional Court considered an issue of attornment when the parties entered into a LTB s.194 settlement of a RTA s.9(1) (application) motion, without the motion yet being resolved:
 The appellant complains that the Board had no jurisdiction over the matter because Bye’s application to determine whether he was in fact a tenant was never decided. I do not agree. The voluntary attornment by the appellant to the jurisdiction of the Board, and her engagement in mediation in relation to Bye’s application, forecloses any argument that would call into question the Board’s jurisdiction: Wolfe v. Wyeth, 2011 ONCA 347, at paras. 42-44, 53. Once the appellant herself agreed to the jurisdiction of the RTA, she must therefore abide by all its rules, including its one-year limitation period for seeking to reopen Bye’s application. . Fraser v 4358376 Canada Inc.
In Fraser v. 4358376 Canada Inc. (Ont CA, 2014) the Court of Appeal addressed the issue of attornment by an allegedly foreign defendant to the jurisdiction of Ontario courts. Here the defendant had brought a motion to challenge the court's jurisdiction, but also moved to add additional parties to the litigation - a step which necessitated some additional and related legal activity on their part. The Court of Appeal held that these further legal acts, being necessary to have all required parties before the court to resolve the jurisdictional issue, did not constitute attornment:
 We agree with the appellants that the motion judge erred in law by concluding that the steps they took amounted to attornment. In our view, all the steps taken by the appellants are more properly characterized as procedural steps taken within the confines of the jurisdiction motion.. Stuart Budd & Sons Limited v. IFS Vehicle Distributors
 By asking for a temporary stay, the appellants were asserting their position that proper resolution of their jurisdictional motion required that the corporate defendants be present before the court. The temporary stay they requested was for that specific and limited purpose.
 In our view, a party who challenges the jurisdiction of the court is entitled to insist upon a proper procedural foundation for the determination of the challenge. Provided that the party’s steps request no more than that, they do not amount to attornment.
 As the motion judge decided that the appellants had attorned by seeking a temporary stay, he did not deal with the argument that by asking the court to strike out the amended statement of claim the appellants had attorned. He dealt with that request on the merits and dismissed it.
 We find it difficult to understand how the appellants could ask the court to strike the amended statement of claim on the basis that the amendment had followed the original jurisdiction motion since it was only through the amendment that they became parties with an interest in proceeding with the motion. We agree with the motion judge’s reasons dismissing that motion on its merits. On the issue of attornment, however, we conclude that the motion to strike the statement of claim, although ill-founded, was entirely based and dependent upon the appellants’ contention that the courts of Ontario had no jurisdiction to entertain the claim. Like the motion for the temporary stay, the motion to strike the claim was nothing more than a request to have the jurisdictional motion proceed on a proper procedural foundation.
 We recognize that decisions of this and other courts have taken a broad view of the kind of steps taken in a proceeding that amount to attornment. See, for example: Wolfe v. Pickar, 2011 ONCA 347 (CanLII), 2011 ONCA 347, 332 D.L.R. (4th) 157; Mid-Ohio Imported Car C. v. Tri-K Investments Ltd. 1995 CanLII 2084 (BC CA), (1995), 129 D.L.R. (4th) 181 (B.C.C.A.). However, the test expressed in those cases is whether the party “…appears in court and goes beyond challenging the jurisdiction of the court based on jurisdiction simpliciter and forum non conveniens”: Wolfe v. Pickar, at para. 44 (emphasis added).
 We know of no authority for the proposition that procedural steps brought within the confines of a jurisdiction motion dealing solely with the mechanics of having that motion heard in a proper procedural setting amount to attornment. In our view that is all that occurred in this case. The appellants did not “go beyond challenging the jurisdiction” and the motion judge erred in law in concluding otherwise.
In Stuart Budd & Sons Limited v. IFS Vehicle Distributors (Ont CA, 2014) the court considered the issue of attornment in the context of a motion to stay an order below pending it's appeal:
 The moving parties assert that they will suffer irreparable harm in several respects if a stay is not granted.. Essar Steel Algoma Inc.
 The moving parties submit that, without a stay, they will be forced to choose between risking attornment to the jurisdiction of the Ontario court by filing a defence, or being noted in default and subjected to default proceedings, either of which would irreparably harm their proposed appeal by rendering it moot.
 I have some difficulty assessing this argument. I say this based on differing views expressed in recent decisions of this court concerning whether a party risks attornment by taking court-ordered steps in a proceeding in the face of an on-going jurisdictional challenge. I refer to the decision in M.J. Jones Inc. v. Kingsway General Insurance Co. 2004 CanLII 6211 (ON CA), (2004), 72 O.R. (3d) 68 (C.A. – Ch’rs) where at paras. 27-31, Lang J.A. dealt with whether a court order requiring a defendant to deliver a statement of defence would amount to attornment. She held that the defendant’s compliance with such an order might amount to attornment. She therefore held that despite the plaintiff’s undertaking not to treat the defendant’s participation as attornment, refusing a stay could cause irreparable harm.
 In BTR Global Opportunity Trading Ltd. v. RBC Dexia Investor Services Trust, 2011 ONCA 620 (CanLII), 2011 ONCA 620, 283 O.A.C. 231, at paras. 28-31, Laskin J.A. distinguished M.J. Jones on the basis that the defendant’s responding to the plaintiff’s request for documents outside of the “formal bounds” of the court proceedings would constitute attornment.
 More recently, in Van Damme v. Gelber, 2013 ONCA 388 (CanLII), 2013 ONCA 388, 115 O.R. (3d) 470, at paras. 21-23, Doherty J.A. noted that attornment by participation in court proceedings had been addressed in Wolfe v. Pickar, 2011 ONCA 347 (CanLII), 2011 ONCA 347, 332 D.L.R. (4th) 157, where, at para. 44, Goudge J.A. said:
[W]hen a party to an action appears in court and goes beyond challenging the jurisdiction of the court based on jurisdiction simpliciter and forum non conveniens, the party will be regarded as appearing voluntarily, thus giving the court consent-based jurisdiction. That is what happened here. Justice Doherty also recognized M.J. Jones and Gourmet Resources International Inc. (Trustee of) v. Paramount Capital Corp. (1991), 5 C.P.C. (3d) 140 (Ont. C.A.) as authorities for the proposition that, if a party appears in a court to challenge jurisdiction or seek a stay on the basis of forum non conveniens, any additional steps taken by the party pursuant to an order of the court will not amount to attornment.
 While Doherty J.A. expressed the view that taking steps in the proceedings further to a court order would not necessarily constitute attornment, advancing a motion for summary judgment, a motion that went beyond a jurisdictional challenge and was not further to any court order was attornment.
 Finally, in Yaiguaje v. Chevron Corp., 2014 ONCA 40 (CanLII), 2014 ONCA 40, 315 O.A.C. 109, at para. 11, MacPherson J.A. (in Chambers), citing Van Damme and BTR, rejected the argument that the party seeking a stay was exposed to irreparable harm based on the risk of attornment.
 Here, the responding parties have undertaking not to argue that the moving parties have attorned to the Ontario jurisdiction “by taking any further steps in the action”.
 I conclude that in the light of this court’s unresolved position on this issue, and the wording of the undertaking in question, the possibility of being found to have attorned creates some risk of irreparable harm to the moving parties.
In Essar Steel Algoma Inc. (Re) (Ont CA, 2016) the Court of Appeal considers in detail the issue of what procedural steps by a party can be undertaken before it is considered to have attorned (accepted) jurisdiction of a court where it otherwise challenges it, here in the context of a stay proceeding on appeal. The test for a stay on appeal is essentially the same as for an interlocutory injunction:
 Over the past decade, judges of this court sitting in Chambers on stay motions have expressed different views about whether a party risks attorning to the jurisdiction of the Ontario court by performing court-ordered procedural steps in the face of the party’s on-going challenge to the court’s jurisdiction. Some decisions have viewed such participation as risking attornment, thereby creating some risk of irreparable harm: M.J. Jones Inc. v. Kingsway General Insurance Co. (2004), 2004 CanLII 6211 (ON CA), 72 O.R. (3d) 68, 242 D.L.R. (4th) 139 (C.A.), at paras. 27-31; Stuart Budd & Sons Ltd. v. IFS Vehicle Distributors ULC, 2014 ONCA 546 (CanLII), 122 O.R. (3d) 472, at paras. 29-36. On the other hand, in Van Damme v. Gelber, 2013 ONCA 388 (CanLII), 115 O.R. (3d) 470, at paras. 21-23, the court minimized any such risk from court-ordered participation, and in Yaiguaje v. Chevron Corp., at para. 11, MacPherson J.A. regarded any risk as a weak factor in the irreparable harm analysis.
 I need not express a view on the effect of court-ordered participation in a proceeding on a party’s ability to continue to advance a jurisdictional challenge because decisions of this court uniformly have held that where the responding party provides the court with undertakings of the kind given by Essar in this case, the undertakings significantly reduce or remove the risk of irreparable harm.
 In BTR Global Opportunity Trading Ltd. v. RBC Dexia Investor Services Trust, 2011 ONCA 620 (CanLII), 283 O.A.C. 321, at para. 14, Laskin J.A. described the undertakings given by BTR:
BTR wants to proceed with the Ontario action. It is content to have LBIE deliver a statement of defence without filing it with the court. It undertakes not to argue that delivery of the statement of defence or participation in examinations for discovery constitute acts of attornment. BTR also undertakes not to invoke the jurisdiction of the Ontario court, by, for example, a motion for summary judgment, while LBIE’s leave motion is outstanding. [Emphasis added.] Laskin J.A. did not consider the delivery of a statement of defence or participation in discoveries outside of the “formal bounds” of the court proceedings as amounting to attornment: at para. 31. Similar undertakings given in Yaiguaje v. Chevron Corp., led MacPherson J.A., at paras. 11 and 16, to follow the decision in BTR Global and conclude that the moving parties had made a very weak showing that they would suffer irreparable harm.
 In light of the undertakings given by Essar to the court in the present case, I conclude that Cliffs have not demonstrated that they would suffer irreparable harm if a stay pending appeal is not granted.