31 C.F.R. § 515.534
(a) Persons subject to the jurisdiction of the United States are authorized to enter into, and to engage in all transactions ordinarily incident to the negotiation of and entry into, contingent contracts for transactions that are prohibited by this part, provided that:
Note to § 515.534: This section does not authorize transactions related to travel to, from, or within Cuba. See § 515.533(c) for a general license authorizing travel-related and other transactions incident to the negotiation of contracts for the exportation or reexportation of certain items to Cuba, and § 515.564(a)(2) for a general license authorizing travel-related and other transactions incident to attending or organizing professional meetings in Cuba, which include professional meetings relating to the negotiation of contingent contracts authorized by this section.
[81 FR 71375, Oct. 17, 2016, as amended at 82 FR 52000, Nov. 9, 2017; 85 FR 60070, Sept. 24, 2020; 87 FR 35089, June 9, 2022]