Illinois courts also consider whether partnership tax returns have been filed, Chen v. Wang, No. 96-C-0681, 1998 WL 27140, at *8 (N.D. Ill. Jan. 16, 1998), and whether the alleged partnership has advertised using a partnership name. Argianas v. Chestler, 631 N.E.2d 1359, 1368 (Ill.App.Ct. 1994). "Additionally, an agreement to form a partnership does not itself create a partnership; the partnership does not arise until the parties actually join together to carry on a common venture, each contributing property or services and each having a community of interest in the profits."

¶ 34 "Whether a partnership exists is a question to be determined by the fact finder from all the facts and circumstances presented." Argianas v. Chestler, 259 Ill. App. 3d 926, 942, 631 N.E.2d 1359, 1369 (1994). "[T]he trial court is in a superior position to make determinations on the credibility of the evidence, and only where the trial court's findings are against the manifest weight of the evidence will a reviewing court overturn the trial court's decision."

805 ILCS 206/101(g) (West 2014). Additionally, Argianas v. Chestler, 259 Ill. App. 3d 926 (1994), which Friedmann cited in support of her argument Ekman's inability to access the business's bank accounts weighs in favor of finding that no partnership existed, is distinguishable. In that case, the parties' written agreement provided that the purported partner was to receive a salary.

The record also shows that, after the parties entered into the 2006 agreements, De Souza received his 5% shares from Simonsen in connection with the revenue generated by the use of the trading software, and that Tradelink provided De Souza with daily statements of Simonsen's trading activity for Tradelink until July 2007. It is undisputed that this array of facts and conflicting interpretations by the parties give rise to more than an inference of materiality. ¶ 32 We find that, based on the foregoing, there exists a genuine material issue as to whether a partnership was created between De Souza and the representatives of Tradelink under the facts and circumstances. See Argianas v. Chestler, 259 Ill. App. 3d 926, 942 (1994) (whether a partnership exists is a question to be determined by the fact finder from all the facts and circumstances presented). Specifically, viewing the record in the light most favorable to De 15 Souza, we cannot conclude as a matter of law whether the time and money that he expended in securing capital from potential investors for the trading software, prior to and after the execution of the Term Sheet and Side Letter, constituted a contribution of "property or services" to the business venture that may be indicative of the existence of a partnership.

In Argianas v. Chestler, the Illinois Appellate Court held that no partnership existed—even though the plaintiff received 40% of the profits from a particular account—where the relevant agreement provided the plaintiff with a salary and did not indicate that a partnership existed. 259 Ill.App.3d 926, 197 Ill.Dec. 900, 631 N.E.2d 1359, 1368–70 (1994). The Argianas court explained that “[a]lthough a sharing of profits is an essential test in determining the existence of a partnership, mere participation in profits, does not alone create a partnership.”

Defendant argues that Plaintiff's only relevant allegations are his share in royalties and profits, and that “mere participation in profits[ ] does not alone create a partnership.” Argianas v. Chestler, 259 Ill.App.3d 926, 942 (1994) (citing Rizzo, 3 Ill.2d at 300). But “[a] person who receives a share of the profits of a business is presumed to be a partner.”

"The requisites of a partnership are that the parties must have joined together to carry on a trade or venture for their common benefit, each contributing property or services, and having a community of interest in the profits." See Argianas v. Chestler, 259 Ill.App.3d 926, 197 Ill.Dec. 900, 631 N.E.2d 1359, 1369 (1994) (citation and internal quotation omitted). "In determining the existence of a partnership, the following factors are material: the manner the parties have dealt with each other; the mode in which each has, with the knowledge of the other, dealt with persons in a partnership capacity; whether the alleged partnership has advertised using the firm name; and whether the alleged partners shared the profits."

Though Holitik and Wagoner are not married, there is evidence that any services Wagoner performed for the business or any loans made to the business stemmed from a personal relationship rather than an intent to form and operate a partnership. See Argianas v. Chestler, 631 N.E.2d 1359, 1369 (Ill. App. Ct. 1994) (citing the manner in which the parties have dealt with each other as a circumstance relevant to the existence of a partnership); Compare Brandenburg v. Brandenburg, 234 Ark. 1117, 1119-20, 356 S.W.2d 625, 627 (1962) (finding that the advancement of money toward the business corroborated the existence of a partnership where advancements were made with the understanding that equipment would be purchased for the business, the name would be changed, and the individual advancing the money would receive one-third of the net profits). Bradbury has failed to present evidence that contradicts Wagoner's and Holitik's affidavits in which they state that they are not co-owners of the business.

¶ 54 A partnership agreement is essentially a contract between the partners and, therefore, is to be interpreted and applied in accordance with principles of contract law. See Argianas v. Chestler (Ill.Ct.App. 1994), 631 N.E.2d 1359, 1368; Klein v. Weiss (Md. 1978), 395 A.2d 126, 141. Where language in a contract is clear and unambiguous, it is a court's duty to simply apply the language. See Molerway Freight Lines, Inc. v. Rite-Line Transp. Serv., Inc. (1995), 273 Mont. 95, 100, 902 P.2d 9, 12; Carbon County v. Dain Bosworth, Inc. (1994), 265 Mont. 75, 87, 874 P.2d 718, 726.

¶ 34 Participation in the profits of a partnership does not automatically create a partnership interest. Argianas v. Chestler, 259 Ill. App. 3d 926, 941, 631 N.E.2d 1359, 1368 (1994) (citing Rizzo v. Rizzo, 3 Ill. 2d 291, 300, 120 N.E.2d 546, 551 (1954)). Furthermore, partner relationships are governed by the partnership agreement, and in this case, the investors are not included as "partners" in the partnership.