0001104659-16-133378 SC TO-I/A 1 20160720 20160719 ATLANTIC POWER CORP 0001419242 4900 550886410 A1 1231 SC TO-I/A 34 005-87139 161774364 3 ALLIED DRIVE SUITE 220 DEDHAM MA 02026 617-977-2400 3 ALLIED DRIVE SUITE 220 DEDHAM MA 02026 ATLANTIC POWER CORP 0001419242 4900 550886410 A1 1231 SC TO-I/A 3 ALLIED DRIVE SUITE 220 DEDHAM MA 02026 617-977-2400 3 ALLIED DRIVE SUITE 220 DEDHAM MA 02026 SC TO-I/A 1 a16-14569_1sctoia.htm SC TO-I/A