X0303 4 2011-03-28 0001471261 Cobalt International Energy, Inc. CIE 0001477020 Whitfield Van P. C/O TWO POST OAK CENTRAL 1980 POST OAK BOULEVARD, SUITE 1200 HOUSTON TX 77056 0 1 0 0 EVP, Operations & Development Common Stock 2011-03-28 4 S 0 2100 15.60 D 590228 D Common Stock 2011-03-28 4 S 0 3100 15.60 D 872304 I footnote Common Stock 2011-03-29 4 S 0 1800 15.60 D 588428 D Common Stock 2011-03-29 4 S 0 2800 15.60 D 869504 I footnote This sale price is a weighted average sale price that represents the sale of these shares of Common Stock at prices ranging from $15.60 to $15.65, 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 within the ranges set forth in footnotes (1) and (2) to this Form 4. This sale price is a weighted average sale price that represents the sale of these shares of Common Stock at prices ranging from $15.60 to $15.64, inclusive. These shares were sold pursuant to a 10b5-1 plan. These shares were sold pursuant to a 10b5-1 plan. These shares of Common Stock are directly owned by Veer Eagles Partners Ltd. /s/ Jeffrey A. Starzec, Attorney-in-Fact 2011-03-30