X0306 4 2017-02-28 0 0001419242 ATLANTIC POWER CORP AT 0001136877 MOORE JAMES J JR C/O ATLANTIC POWER CORPORATION 3 ALLIED DRIVE, SUITE 220 DEDHAM MA 02026 1 1 0 0 Chief Executive Officer Notional shares 2017-02-28 4 A 0 229517 A Common shares 229517 422254 D Represents a grant of notional shares pursuant to the Company's Long-Term Incentive Plan (LTIP) in 2017 in respect of the 2016 performance year. 50% of these notional units, or 114,759, will vest ratably with respect to one-third on each of February 28, 2018, February 28, 2019 and February 28, 2020. The remaining 50% will also vest one-third on each of February 28, 2018, February 28, 2019 and February 28, 2020, the amount being at the discretion of the Board of Directors. 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. The 192,737 notional shares granted to Mr. Moore and reported on Form 4 on March 8, 2016 incorrectly stated that they vest ratably with respect to one-third on each of February 28, 2017, February 28, 2018 and February 28, 2019. These notional units will vest on the three year anniversary of the date grant. The amount of notional units that will vest on that date can range from 0% to 150% of the original grant amount based on the Company's total shareholder return relative to a pre-approved peer group of companies. /s/ James J. Moore, Jr. 2017-03-03