X0306 4 2019-02-26 0 0001419242 ATLANTIC POWER CORP AT 0001136877 MOORE JAMES J JR C/O ATLANTIC POWER CORPORATION 3 ALLIED DRIVE, SUITE 155 DEDHAM MA 02026 1 1 0 0 Chief Executive Officer Common shares 2019-02-26 4 M 0 128491 A 890174 D Common shares 2019-02-26 4 F 0 64246 2.72 D 890174 D Common shares 2019-02-26 4 M 0 51004 A 890174 D Common shares 2019-02-26 4 F 0 25502 2.72 D 890174 D Common shares 2019-02-26 4 M 0 63571 A 890174 D Common shares 2019-02-26 4 F 0 31786 2.72 D 890174 D Notional shares 2019-02-26 4 M 0 192737 2.72 D Common shares 192737 478616 D Notional shares 2019-02-26 4 M 0 76506 2.72 D Common shares 76506 478616 D Notional shrares 2019-02-26 4 M 0 95357 2.72 D Common shares 95357 478616 D Notional shares 2019-02-26 4 A 0 211397 A Common shares 211397 478616 D The reporting person acquired shares pursuant to the vesting (disclosed on Table II) of notional shares awarded in 2016. Two thirds of the vested notional shares were settled in common shares and one third were settled in cash, which was deposited into the reporting persons applicable payroll tax withholding account. The reporting person acquired shares pursuant to the vesting (disclosed on Table II) of notional shares awarded in 2017. Two thirds of the vested notional shares were settled in common shares and one third were settled in cash, which was deposited into the reporting persons applicable payroll tax withholding account. The reporting person acquired shares pursuant to the vesting (disclosed on Table II) of notional shares awarded in 2018. Two thirds of the vested notional shares were settled in common shares and one third were settled in cash, which was deposited into the reporting persons applicable payroll tax withholding account. The reporting person vested in respect of 100% of the notional shares granted in 2016. The reporting person vested in respect of one third of the notional shares granted in 2017. The reporting person vested in respect of one third of the notional shares granted in 2018. Represents a grant of notional shares pursuant to the Company's Long-Term Incentive Plan (LTIP) in 2019 in respect of the 2018 performance year, which will vest ratably with respect to one-third on each of February 28, 2020, February 28, 2021 and February 28, 2022. Under the LTIP, each notional share represents a right to receive one-third in cash, which will be deposited into the reporting persons applicable payroll tax withholding account, and the remainder in common shares. /s/ John S. Miele, attorney-in-fact 2019-02-28