X0609 4 2026-09-15 0001750704 HawkEye 360, Inc. HAWK 0001836524 Turner Michael S. false C/O HAWKEYE 360, INC. 450 SPRINGPARK PLACE, SUITE 500 HERNDON VA 20170 false true false false Chief Legal Officer 1 Common Stock 2026-09-15 4 S 0 8250 16.2888 D 197777 D Common Stock 2026-09-16 4 S 0 18256 16.2368 D 179521 D The sale reported on this Form 4 represents shares sold by the Reporting Person to cover tax withholding obligations in connection with the vesting and settlement of RSUs. The sale is mandated by the Issuer's election to require the satisfaction of tax withholding obligations to be funded by a "sell to cover" transaction and does not represent a discretionary transaction by the Reporting Person. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.06 to $16.51 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold each separate price within the range set forth in this footnote. Represents shares sold pursuant to a Rule 10b5-1 Plan adopted on May 21, 2026. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $16.02 to $16.52 inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold each separate price within the range set forth in this footnote. /s/ Michael S. Turner 2026-09-17