X0609 4 2026-05-28 0 0001776909 CuriosityStream Inc. CURI 0001827441 Stinchcomb Clinton Larry false 8484 GEORGIA AVE., SUITE 700 SILVER SPRING MD 20910 1 1 0 0 President and CEO 0 Common Stock 2026-05-28 4 P 0 25744 2.777 A 2971260 D Restricted Stock Units Common Stock 1200000 1200000 D The price reported in Column 4 is a weighted average price. These shares were purchased in multiple transactions at prices ranging from $2.75 to $2.78, inclusive. The reporting person undertakes to provide to CuriosityStream Inc., any security holder of CuriosityStream Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price within the ranges set forth in this footnote to this Form 4. On July 15, 2025, the Company granted Mr. Stinchcomb 2,400,000 restricted stock units (RSUs) with tandem dividend equivalent rights under the 2020 Omnibus Incentive Plan. Each RSU represents the right to receive one share of common stock and will be settled upon vesting (or within 30 days thereafter). All vesting events are subject to continued employment on each applicable vesting date. The RSUs granted are performance-based, subject to the Company achieving certain stock price or financial performance goals. On August 4, 2025, the Board determined that the Company met the first performance condition of the award by achieving 35% year-over-year revenue growth for the period January 1 through June 30, 2025, compared to the same period in 2024, and thereby triggering the vesting of the first tranche of the Award, or 600,000 RSUs. On March 10, 2026, the Board determined that the Company met the second performance condition of the award by achieving 40% revenue growth and 35% adjusted free cash flow growth for the full year 2025 compared to 2024, and thereby triggering the vesting of the second tranche of the Award, or 600,000 RSUs. Mr. Stinchcomb now has 1,200,000 remaining unvested RSUs under the award as reported in Table II. /s/ P. Brady Hayden as attorney-in-fact for Clint Stinchcomb 2026-06-01