X0306 4 2020-09-30 0 0001000694 NOVAVAX INC NVAX 0001342826 Erck Stanley C C/O NOVAVAX, INC. 21 FIRSTFIELD ROAD GAITHERSBURG MD 20878 1 1 0 0 President and CEO Common Stock 2020-09-30 4 S 0 517 107.5609 D 32210 D Common Stock 2020-09-30 4 S 0 5138 108.563 D 27072 D Common Stock 2020-09-30 4 S 0 1500 109.536 D 25572 D Common Stock 2020-09-30 4 S 0 1676 110.5428 D 23896 D Common Stock 2020-09-30 4 S 0 900 111.4122 D 22996 D Common Stock 2020-09-30 4 S 0 800 112.6475 D 22196 D Common Stock 2020-09-30 4 S 0 700 114.20 D 21496 D Common Stock 2020-09-30 4 S 0 800 114.73 D 20696 D Common Stock 2020-09-30 4 S 0 100 115.43 D 20596 D Common Stock 2020-09-30 4 S 0 100 115.65 D 20496 D Common Stock 2020-10-01 4 S 0 2 108.565 D 20494 D The transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person. The reported price is a weighted average price. These shares were sold in multiple transactions at prices ranging from $107.00 to $107.90, inclusive. The reporting person undertakes to provide to Novavax, Inc. (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission (the "SEC"), 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 $108.02 to $109.00, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $109.05 to $110.01, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $110.09 to $111.05, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $111.10 to $111.85, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $112.25 to $113.09, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $113.29 to $114.20, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, 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 $114.40 to $115.11, inclusive. The reporting person undertakes to provide to the Company, any security holder of the Company, or the staff of the SEC, upon request, full information regarding the number of shares purchased at each price within the range set forth in this footnote. /s/ John A. Herrmann III, Attorney-in-Fact 2020-10-01