X0508 4 2026-03-10 0 0001758009 Quantum Computing Inc. QUBT 0001757685 Roberts Christopher Bruce 5 MARINE VIEW PLAZA, SUITE 214 HOBOKEN NJ 07030 0 1 0 0 CFO and General Counsel 0 Common Stock 2026-03-10 4 M 0 400000 6.85 A 1201300 D Common Stock 2026-03-10 4 S 0 68902 7.8518 D 1132398 D Common Stock 2026-03-11 4 S 0 9360 7.8520 D 1123038 D Employee Stock Option (right to buy) 6.85 2026-03-10 4 M 0 400000 0.0 D 2026-05-25 Common Stock 400000 300000 D Sale of shares to cover the exercise price, withholding tax obligations and broker fees and commissions, pursuant to a broker assisted cashless exercise of vested stock options granted on April 26, 2021 under the 2019 Quantum Computing Inc. Equity and Incentive Plan. The price reported in Column 4 is a weighted-average price. These shares were sold in multiple transactions at prices ranging from $7.8500 to $7.8550 on March 10, 2026 and March 11, 2026. The Reporting Person undertakes to provide the Registrant, any securityholder of the Registrant, or the Staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The stock option was granted on April 26, 2021 (the "Date of Grant"), and had a vesting commencement date of April 26, 2021. The options vested as follows: (i) 150,000 Options vested immediately upon grant (ii) 83,333 Options vested on the 12-month anniversary of the Date of Grant (iii), 83,333 Options vested on the 24-month anniversary of the Date of Grant and (iv) 83,334 Options vested on the 36-month anniversary of the Date of Grant. /s/ Christopher Bruce Roberts 2026-03-11