Material Agreement, Private Placement (Form 8-K)

On December 22, 2025, ScanTech AI Systems Inc. (the "Company") and Vanquish Funding Group Inc. ("Vanquish") entered into a securities purchase agreement (the "Agreement"). Pursuant to the terms of the Agreement, the Company issued a convertible promissory note (the "Note") to Vanguish with a total principal amount of up to $270,900. The Note bears interest at an annual rate of 10% and matures on October 22, 2026 (the "Maturity Date"). The Note further bears an original issue discount price of $12,900.

Vanquish has the right, but not the obligation, to convert, at any time following 180 days following the date of the Agreement and the Note and prior to the later of the Maturity Date or the date of payment of the Default Amount (as defined below), all or any portion of the outstanding Principal Amount, accrued interest and fees due and payable thereon into shares (the "Conversion Shares") of the Company's common stock. Conversion Shares shall refer to any unpaid principal amount and interest as of the date of the conversion notice, plus any shares that should be issued, should Default Interest (as defined below) be applied. The conversion price for the Conversion Shares is equal to 75% of the average of the two lowest trading prices for the Company's common stock during the ten trading day period preceding the conversion date. "Trading Price" means the price at which a trade of the Company's common stock is reported by a reliable reporting service designated by Vanquish. Vanquish is prohibited from converting an amount that would be convertible into that number of Conversion Shares which would exceed the difference between the number of shares of the Company's common stock beneficially owned by Vanquish and 4.99% of the outstanding shares of the Company's common stock. The Lender may not waive such 4.99% limitation. For purposes of the Note, "Default Amount" shall mean an amount equal to 150% times the sum of, as of the date of the payment of the Default Amount, (i) the remaining principal amount of the Note, (ii) any unpaid and accrued interest; and (iii) an interest rate of 22% on any amount principal or interest remaining (the "Default Interest").

Moreover, the Note provides that in no event will the Company be required to (i) issue shares of Company's common stock (or securities convertible into or exercisable for the Company's common stock), exceeding 19.99% of the Company's common stock or exceeding 19.99% of the voting power outstanding, as determined in accordance with the relevant stock exchange rules (the "Conversion Cap"), and (ii) otherwise issue shares of the Company's common stock or other securities which issuance would violate any rule of the Securities and Exchange Commission (the "SEC") or the relevant stock exchange or trading market on which the Company's common stock is then listed or quoted, unless stockholder approval is obtained pursuant to Rule 5635(d) of the Nasdaq Stock Market rules.

Additionally, the Company may prepay, in full, the outstanding principal amount and any unpaid interest by giving Vanquish three days written notice. In the event the Company chooses to prepay the Note, the Company shall prepay the sum of all outstanding unpaid principal amount, all unpaid and accrued interest, and Default Interest, if any, multiplied by 120% should the prepayment come within 90 days of the date of the Note, or shall be multiplied by 125% should the prepayment notice come within 91 days and 190 days following the date of the Note.

The information set forth under Item 1.01 above is incorporated by reference into this Item 2.03.

The information set forth under Item 1.01 above is incorporated by reference into this Item 3.02.

The Company expects to issue the Conversion Shares in reliance on the exemption from the registration requirements of the Securities Act, provided by Section 4(a)(2) under the Securities Act as a transaction not involving a public offering.