As of my last update in October 2023, there hasn't been a specific negotiation or final purchase agreement that stands out between France and the United States that would warrant detailed information. However, historically, the two countries have engaged in various negotiations and agreements covering a wide range of topics including trade, defense, and technology.
One notable area of cooperation has been in defense, with agreements related to military procurement, arms sales, and joint projects, such as the F-35 fighter jet program and other defense initiatives.
If you have a particular context or specific deal in mind—instead of a general overview—please provide more details, and I would be glad to offer more relevant information based on that.