X0609 4 2026-09-30 0 0001759631 Hyliion Holdings Corp. HYLN 0001946212 Panzer Jon false C/O HYLIION HOLDING CORP. 1202 BMC DRIVE, SUITE 100 CEDAR PARK TX 78613 0 1 0 0 Chief Financial Officer 0 Common Stock 2026-09-30 4 C 0 59210 0 A 994690 D Common Stock 2026-09-30 4 C 0 75457 0 A 1070147 D Performance Stock Incentive Units 2026-09-30 4 C 0 59210 0 D 2026-02-18 2027-12-31 Common Stock 59210 236843 D Performance Stock Incentive Units 2026-09-30 4 C 0 75457 0 D 2028-12-31 2028-12-31 Common Stock 75457 226373 D The underlying market conditions for vesting of this portion of performance stock incentive units ("PSU Award") were satisfied on September 28, 2026, and subsequently approved by the Compensation Committee on September 30, 2026. Half of the vested PSUs will be issued on September 30, 2027 with the remainder to be issued on December 31, 2027. The underlying market conditions for vesting of this portion of performance stock incentive units ("PSU Award") were satisfied on September 28, 2026, and subsequently approved by the Compensation Committee on September 30, 2026. These vested PSUs will be issued on December 31, 2028. 25% of these PSU Awards vested upon the achievement of the underlying closing stock price threshold of a minimum of $4.00 per share over a 180-calendar-day average. 20% of these PSU Awards vested upon the achievement of the underlying closing stock price threshold of a minimum of $4.00 per share over a 180-calendar-day average. /s/ Jon Panzer 2026-10-01