X0306 4 2021-09-30 0 0001866692 Amplitude, Inc. AMPL 0001882998 Johnson Jennifer L. C/O AMPLITUDE, INC. 201 THIRD ST., SUITE 200 SAN FRANCISCO CA 94103 0 1 0 0 See remarks Class A Common Stock 2021-09-30 4 M 0 250477 4.19 A 250477 D Class A Common Stock 2021-09-30 4 S 0 17400 52.9286 D 233077 D Class A Common Stock 2021-09-30 4 S 0 233077 53.918 D 0 D Class A Common Stock 2021-10-01 4 M 0 80773 4.19 A 80773 D Class A Common Stock 2021-10-01 4 S 0 16472 50.9872 D 64301 D Class A Common Stock 2021-10-01 4 S 0 16804 51.9414 D 47497 D Class A Common Stock 2021-10-01 4 S 0 14882 53.2761 D 32615 D Class A Common Stock 2021-10-01 4 S 0 32615 54.2258 D 0 D Stock Option (Right to Buy) 4.19 2021-09-30 4 M 0 250477 0.00 D 2030-11-10 Class A Common Stock 250477 1074523 D Stock Option (Right to Buy) 4.19 2021-10-01 4 M 0 80773 0.00 D 2030-11-10 Class A Common Stock 80773 993750 D This transaction was executed in multiple trades in prices ranging from $52.41 to $53.36, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. This transaction was executed in multiple trades in prices ranging from $53.41 to $54.39, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. This transaction was executed in multiple trades in prices ranging from $50.61 to $51.60, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. This transaction was executed in multiple trades in prices ranging from $51.69 to $52.68, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. This transaction was executed in multiple trades in prices ranging from $52.75 to $53.74, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. This transaction was executed in multiple trades in prices ranging from $53.75 to $54.70, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. 25% of the shares subject to the option vest on the first anniversary measured from September 30, 2020 (the "Vesting Commencement Date"), and 1/48th of the total number of shares vest monthly thereafter, such that 100% of the shares subject to the option will be fully vested and exercisable on the fourth anniversary of the Vesting Commencement Date. Chief Marketing and Strategy Officer /s/ Hoang Vuong, as Attorney-in-Fact for Jennifer L. Johnson 2021-10-01