X0306 4 2021-03-23 0 0001000694 NOVAVAX INC NVAX 0001219864 YOUNG JAMES F C/O NOVAVAX, INC. 21 FIRSTFIELD ROAD GAITHERSBURG MD 20878 1 0 0 0 Common Stock 2021-03-23 4 M 0 10000 46.00 A 20000 D Common Stock 2021-03-23 4 S 0 4434 227.4324 D 15566 D Common Stock 2021-03-23 4 S 0 3120 228.4171 D 12446 D Common Stock 2021-03-23 4 S 0 2446 229.4089 D 10000 D Common Stock 2021-03-25 4 M 0 10000 27.60 A 20000 D Common Stock 2021-03-25 4 M 0 37500 3.985 A 57500 D Common Stock 1500 I By spouse Stock Option (Right to Buy) 46.00 2021-03-23 4 M 0 10000 0.00 D 2019-12-13 2028-12-13 Common Stock 10000 0 D Stock Option (Right to Buy) 27.60 2021-03-25 4 M 0 10000 0.00 D 2018-12-15 2027-12-15 Common Stock 10000 0 D Stock Option (Right to Buy) 3.985 2021-03-25 4 M 0 37500 0.00 D 2020-12-12 2029-12-12 Common Stock 37500 0 D The reported price is a weighted average price. These shares were sold in multiple transactions at prices ranging from $227.00 to $227.61, inclusive. The reporting person undertakes to provide to Novavax, Inc., any security holder of Novavax, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each price within the range set forth in this footnote. The reported price is a weighted average price. These shares were sold in multiple transactions at prices ranging from $228.00 to $228.89, inclusive. The reporting person undertakes to provide to Novavax, Inc., any security holder of Novavax, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each price within the range set forth in this footnote. The reported price is a weighted average price. These shares were sold in multiple transactions at prices ranging from $229.00 to $229.65, inclusive. The reporting person undertakes to provide to Novavax, Inc., any security holder of Novavax, Inc., or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each price within the range set forth in this footnote. The reporting person disclaims beneficial ownership of these securities, and this report shall not be deemed an admission that the reporting person is the beneficial owner of the securities for purposes of Section 16 or for any other purpose. One hundred percent (100%) of the shares subject to this option grant under the Novavax, Inc. Amended and Restated 2015 Stock Incentive Plan, as amended (the "Plan") vested one (1) year from the December 13, 2018 grant date. One hundred percent (100%) of the shares subject to this option grant under the Plan vested one (1) year from the December 15, 2017 grant date. One hundred percent (100%) of the shares subject to this option grant under the Plan vested one (1) year from the December 12, 2019 grant date. /s/ John A. Herrmann III, Attorney-in-Fact 2021-03-25