Plaintiff Amanda May sued her employer Higbee Co. (d/b/a Dillard’s) and a supervisor for employment discrimination under Title VII. The defendants moved to compel arbitration and to stay the judicial proceedings. The district court denied the motion, ruling that May had not assented to her employer’s arbitration program. Concluding that the district court should have ordered arbitration pursuant to the parties’ binding agreement, we reverse.
I. FACTUAL AND PROCEDURAL BACKGROUND
May began working at a Dillard’s department store in June 1990, and she later rose to become the sales manager of the store’s men’s department. May alleges that she was qualified to be promoted to higher managerial positions but was repeatedly passed over in favor of male employees. The particular employment action that precipitated this lawsuit occurred in March 2002, when May was denied a promotion to the position of assistant store manager. According to May, her supervisor, William Carr, refused to promote May into higher-level management positions because she was a woman and a mother. *759 May filed suit in the district court in June 2002, claiming that Dillard’s and Carr had discriminated against her on the basis of her sex in violation of Title VII, 42 U.S.C. § 2000e et seq. (2000).
The defendants later filed a motion to compel arbitration and to stay the judicial proceedings. The motion was based on the fact that, in June 2001, the company had instituted a compulsory arbitration program for most employment-related disputes. May admits to receiving two documents relating to the arbitration program. One document, titled “Rules of Arbitration” (the “Rules”), states that both the company and the employee “agree that the procedures provided in these Rules will be the sole method used to resolve any covered dispute arising between them.” The Rules go on to list employment discrimination claims as among the covered disputes. Although the Rules state that they apply to disputes that arise between employees and “the Company,” the last page of the document defines “the Company” broadly, so that the term includes the corporate entity and its managers and employees, such as Carr.
The second document that May received was a one-page form titled “Acknowledgment of Receipt of Rules for Arbitration” (the “Acknowledgment Form”). The Acknowledgment Form included the following language in readily legible type:
Effective immediately, all employees ... shall be subject to the RULES OF ARBITRATION (the “Rules”) described below. Employees are deemed to have agreed to the provisions of the Rules by virtue of accepting employment with the Company and/or continuing employment therewith.
Below this paragraph, and immediately above the signature line, was text stating that “I acknowledge receipt of the agreement to arbitrate certain claims and rules of arbitration.” May admits that she signed such an Acknowledgment Form. 1 As a supervisory employee, May was also involved in distributing the documents to lower-level employees and in obtaining their signatures.
May filed a response to the defendants’ motion, in which she claimed, inter alia, that she had not actually agreed to arbitrate but had instead only acknowledged that she had received certain documents. Her response further stated that Carr had told her that arbitration would be optional for employees like her and had also told her that the Acknowledgment Form only indicated that she had received the Rules, nothing more.
The district court denied the defendants’ motion in a written opinion and order dated August 26, 2003. The court agreed with May that there was no binding agreement to arbitrate because May never assented to be bound by the company’s arbitration procedures. While noting that parol evidence is generally inadmissible to vary the terms of a written contract, the district court concluded that parol evidence was allowable in this case because the acknowledgment form was ambiguous. The form was ambiguous, in the district court’s view, because it was internally inconsistent: The title of the form and the text immediately above the signature line stated only that May acknowledged receiving the Rules, but the language in the body of the form (language that we quoted above) stated that May agreed to be bound *760 by the Rules. To resolve the ambiguity regarding what May had agreed to, the district court looked to May’s evidence about Carr’s contemporaneous statements. Since the defendants had not denied May’s account of Carr’s statements, the district court credited May’s evidence and concluded that May had not agreed to compulsory arbitration. The court further held that the defendants’ motion to compel arbitration should be denied because an ambiguous agreement should be construed against its drafter, here Dillard’s.
The defendants timely filed a notice of appeal and, on the same day, also filed a motion to certify the district court’s decision for interlocutory appeal under 28 U.S.C. § 1292(b). 2 The district court denied the motion to certify an interlocutory appeal. The defendants have argued that the motion to certify was unnecessary and was undertaken only out of caution, since (according to the defendants) they can pursue an interlocutory appeal as of right under 9 U.S.C. § 16(a)(1). 3 May has filed a motion to dismiss the appeal for want of appellate jurisdiction. 4
II. APPELLATE JURISDICTION
Perhaps the most hotly contested issue in this case is the threshold question of whether we have jurisdiction to entertain this appeal. The defendants do not contend that the district court’s decision to deny their arbitration motion is a decision that would ordinarily be appealable as a final order. The defendants do point out, however, that Congress has expressly authorized us to hear certain arbitration-related interlocutory appeals. The jurisdictional statute provides, in relevant part:
(a) An appeal may be taken from—
(1) an order—
(A) refusing a stay of any action under section 3 of this title, 5
(B) denying a petition under section 4 of this title to order arbitration to proceed, 6
*761 (3) a final decision with respect to an arbitration that is subject to this title.
(b) Except as otherwise provided in section 1292(b) of title 28, an appeal may not be taken from an interlocutory order—
(1) granting a stay of any action under section 3 of this title;
(2) directing arbitration to proceed under section 4 of this title....
9 U.S.C. § 16 (2000) (emphasis added). Enacted in 1988, section 16 reinforces the congressional policy in favor of arbitration by making anti-arbitration decisions widely appealable even when interlocutory, but making pro-arbitration decisions generally not appealable unless final.
7
See Green Tree Fin. Corp.-Ala. v. Randolph,
The defendants moved the district court to compel arbitration and stay the judicial proceedings under 9 U.S.C. §§ 3 and 4, but the district court denied their motion. That denial is the type of decision for which § 16(a)(1) would appear to confer the right to bring an interlocutory appeal. But May contends that the district court’s decision is not immediately appeal-able, via § 16(a)(1) or otherwise, and she cites in support of her view the recent decision of this court in
Cerveceria Cuauhtemoc Moctezuma S.A. de C.V. v. Montana Beverage Co.,
The parties in
Cervecería
had entered into a distributorship agreement. The contract did not contain an arbitration clause, though it did incorporate by reference the entirety of the Texas Beer Industry Fair Dealing Law (BIFDL), Tex. AlCO. Bev.Code AnN. §§ 102.71-81 (Vernon 1995). One particular section of the BIFDL provides that certain disputes “may, at the option of either [party]” be submitted to an arbitration panel. A dispute led one of the parties to file suit in the district court, and in response the other party moved the district court to stay the proceedings and compel arbitration under 9 U.S.C. §§ 3 and 4. The district court refused, finding that there was no binding agreement to arbitrate. This court agreed that there was no binding agreement to arbitrate; the court concluded, moreover, that the absence of any such agreement deprived the court of appellate jurisdiction to entertain the interlocutory appeal.
Cervecería
was an exceptional case. It appears that there is only one other published decision of this court that has dismissed an appeal of an anti-arbitration ruling for failure to satisfy the requisites of § 16(a)(1). That case was
Adams v. Georgia Gulf Corp.,
We conclude that the instant case provides no occasion to deviate from the general, congressionally mandated rule that anti-arbitration decisions are immediately appealable under § 16(a)(1). In particular, unlike the situation in
Cervecería,
here the proponents of arbitration have produced documents, which the plaintiff admits she signed, that purport to be an agreement between the parties to arbitrate their dispute. The district court simply ruled that the documents, due to a purported lack of mutual assent, did not constitute a binding agreement as a matter of state law. In
Cervecería,
by contrast, the proponent of arbitration could point to nothing more than a general cross-reference to a state code, which code itself did not even contemplate mandatory arbitration of the parties’ dispute.
Although the circumstances of today’s case are very different from the unusual situation in
Cervecería,
May nonetheless directs us to certain broad language in
Cervecería
that seems to suggest that our appellate jurisdiction under § 16 turns wholly on whether
the district court
thought that the parties had entered into a clear, binding agreement to arbitrate.
See
III. MERITS
Satisfied of our jurisdiction, we turn now to the question whether the district court erred in denying the defendants’ motion to compel arbitration and to stay the judicial proceedings. Our guiding principle in this inquiry is the rule that “arbitration is a matter of contract and a party cannot be required to submit to arbitration any dispute which he has not agreed so to submit.”
AT&T Techs., Inc. v. Communications Workers of Am.,
In reaching its decision, the district court held as a matter of law that the Acknowledgment Form was ambiguous with regard to whether May’s signature indicated that she agreed to be bound by the Rules or only that she agreed that she had received the Rules. Resolving that ambiguity with parol evidence of Carr’s statements, the district court held that May had not in fact assented to binding arbitration but had only agreed that she had received certain forms. On appeal, May defends the district court’s decision on the same basis. 11 For their part, the *764 defendants argue that the district court fundamentally misunderstood the nature and purpose of the Acknowledgment Form. May’s signing the Acknowledgment Form, according to the defendants, was not meant to be a manifestation of assent to be bound by the Rules. Rather, they contend, the Acknowledgment Form merely put May on notice that continued employment would constitute assent, and May in fact manifested that assent by remaining employed at the Dillard’s store.
As the district court correctly recognized, the question whether the parties formed a valid agreement to arbitrate is a matter governed by principles of state contract law,
see Wash. Mut. Fin. Group, LLC v. Bailey,
Having considered the parties’ arguments and the record, we conclude that the district court erred in its reading of the relevant documents and misunderstood how the documents worked together to create a binding agreement to arbitrate. The district court concluded that the Acknowledgment Form was internally inconsistent because, in the court’s view, the form announced itself as both a mere acknowledgment that May had received documents and at the same time pm-ported to bind May to arbitration. Properly construed, however, the Acknowledgment Form and May’s signature thereon did not by themselves constitute May’s assent to arbitration. By signing the Acknowledgment Form, May indicated that she had received the Rules, but the signature did not all by itself bind May to the arbitration program. Rather, May became bound through her subsequent conduct, for the Acknowledgment Form unambiguously notified May that “[e]mployees are deemed to have agreed to the provisions of the Rules by virtue of ... continuing employment [with Dillard’s].” In other words, the Acknowledgment Form notified May of how she would manifest her assent to be bound. She undisputedly continued her employment at Dillard’s, thus manifesting assent in the requested manner. The district court should not have looked to May’s evidence regarding Carr’s statements to vary the terms of the unambiguous writings that were before it.
See United States Small Bus. Admin. v. Guar. Bank & Trust Co. (In re Whatley),
Continuing one’s employment after receiving notice that continued employment will constitute assent is a recognized manner of forming a contract. As a general matter, Mississippi courts have long held that a party’s conduct may manifest assent to an agreement.
See Edwards v. Wurster Oil Co.,
In addition to arguing that she had not assented to the arbitration program, May’s submissions in the district court also contended that the arbitration agreement would be unconscionable and that there was no consideration for her promise to arbitrate. May’s brief on appeal does not offer any argument on those theories, and we express no opinion on whether the arbitration agreement could be challenged on those grounds. We hold only that the district court erred in determining that the parties’ putative contract lacked the element of mutual assent.
IV. CONCLUSION
For the foregoing reasons, May’s motion to dismiss the appeal is DENIED, the district court’s judgment is REVERSED, and the cause is REMANDED to the district court for entry of an appropriate order granting the defendants’ request for arbitration. 14 Costs shall be borne by May.
Notes
. The actual form that May signed could not be located in her personnel file and was not submitted in support of the defendants' motion. Nonetheless, May admitted in her deposition that she signed a document titled “Acknowledgment of Receipt of Rules for Arbitration,” and she did not offer any evidence suggesting that the form she signed differed from the examples of the Acknowledgment Form that appear in the record.
. 28 U.S.C. § 1292(b) provides, in pertinent part:
When a district judge, in making in a civil action an order not otherwise appealable under this section, shall be of the opinion that such order involves a controlling question of law as to which there is substantial ground for difference of opinion and that an immediate appeal from the order may materially advance the ultimate termination of the litigation, he shall so state in writing in such order.
. The defendants took the same position below, writing in their motion to certify an appeal that certification was sought only as a precautionary measure.
. May also filed a motion to supplement the record on appeal with certain discovery materials that were not presented to the district court. Ordinarily, we will not permit a litigant to supplement the record with material that was not before the district court.
See Peoples Nat’l Bank v. Comptroller of the Currency,
In addition, the defendants filed a motion to certify certain questions to the Mississippi Supreme Court. We find, however, that we are able to dispose of this case in a manner that does not implicate any unsettled questions of state law that would justify certification.
. Section 3, which concerns stays of judicial proceedings pending arbitration, provides as follows:
If any suit or proceeding be brought in any of the courts of the United States upon any issue referable to arbitration under an agreement in writing for such arbitration, the court in which such suit is pending, upon being satisfied that the issue involved in such suit or proceeding is referable to arbitration under such an agreement, shall on application of one of the parties stay the trial of the action....
. Section 4, which involves requests to compel arbitration, provides as follows:
*761 A party aggrieved by the alleged failure, neglect, or refusal of another to arbitrate under a written agreement for arbitration may petition any United States district court which, save for such agreement, would have jurisdiction under title 28, in a civil action or in admiralty of the subject matter of a suit arising out of the controversy between the parties, for an order directing that such arbitration proceed in the manner provided for in such agreement.
. Section 16 was originally numbered § 15, but it was renumbered in 1990.
. We observe that our cases have not uniformly endorsed Adams's view regarding whether § 3’s mandatory stay provision is available in such a case. In Hill v. GE Power Sys., Inc., 282 F.3d 343 (5th Cir.2002), we noted that § 3 generally applies only as between parties to an arbitration agreement, but we nonetheless held that a defendant who was not a party to an arbitration agreement could invoke § 3’s mandatory stay in certain cases in which the plaintiffs claims against that defendant were inseparable from the plaintiff’s claims against a defendant with whom the plaintiff had entered into a binding arbitration agreement. Id. at 346-48. Hill also specifically addressed the issue of appellate jurisdiction and held that the non-signatory defendant could use § 16(a)(1) to bring an appeal. Id. at 348. As the arbitration agreement at issue in today’s case explicitly covers May’s claims against Carr, as well as her claims against Dillard's, we have no occasion to resolve any disharmony in our circuit’s cases regarding the rights of litigants who are not actually parties to an arbitration agreement.
. Despite this language,
Cervecería
still in fact reviewed the merits of the district court’s decision that there was no agreement to arbitrate, albeit as a round-about way to determine whether there was appellate jurisdiction.
See
. May's proffered limitation on § 16(a)(1) would also conflict with the views of other circuits, which recognize that the inquiry on interlocutory appeal includes the question whether there exists a binding contract.
See, e.g., Specht v. Netscape Communications Corp.,
. Although the district court’s reliance on May’s evidence regarding her supervisor's comments was primarily based on the court's determination that the documents were ambiguous, the court also deemed it proper to consider such evidence because the actual form that May signed had been lost. Yet there is no genuine dispute on this record as *764 to the contents of the form that May signed, see supra note 1, and May’s brief does not argue that the unavailability of the actual form justified the use of parol evidence. Our analysis, like May's, will confine itself to the question whether the agreement was ambiguous.
. As her counsel admitted during oral argument in this court, May has not contended that she was fraudulently induced into entering into the arbitration agreement, which might have provided a reason to examine Carr’s statements.
. Moreover, a state would not be permitted to employ special rules of contract formation that apply only to arbitration agreements.
See
9 U.S.C. § 2 (2000);
Doctor’s Assocs. v. Casarotto,
. We also dispose of the following outstanding motions as follows: May's motion to supplement the record on appeal is DENIED, the defendants’ motion to order May to file corrected record excerpts is DENIED AS MOOT, and the defendants’ motion to certify questions to the Mississippi Supreme Court is DENIED. See supra note 4.
