X0304 4 2011-12-20 0001471261 Cobalt International Energy, Inc. CIE 0001477019 Farnsworth James W. C/O TWO POST OAK CENTRAL 1980 POST OAK BOULEVARD, SUITE 1200 HOUSTON TX 77056 0 1 0 0 Chief Exploration Officer Common Stock 2011-12-20 4 S 0 80000 13.44 D 2306691 D This sale price is a weighted average sale price that represents the sale of these shares of Common Stock at prices ranging from $13.05 to $13.98, inclusive. These shares were sold pursuant to a 10b5-1 plan. The reporting person undertakes to provide upon request by the SEC staff, the Issuer or any security holder of the Issuer, full information regarding the number of shares of Common Stock sold at each separate price. /s/ Jeffrey A. Starzec, Attorney-in-Fact 2011-12-22