X0303 4 2011-05-10 0 0001110805 NuStar Energy L.P. NS 0001015543 GREEHEY WILLIAM E 2330 NORTH LOOP 1604 WEST SAN ANTONIO TX 78248 1 0 0 0 Common Units 2011-05-10 4 P 0 38000 64.1009 A 1278945 D Common Units 2011-05-11 4 P 0 38000 63.1367 A 1316945 D This transaction was executed in multiple trades at prices ranging from $63.87 per unit to $64.23 per unit. The price reported above reflects the weighted average purchase price. Note that due to field restrictions in Table I, Column 4, the last decimal place does not appear. The total weighted average purchase price is actually $64.10089. Upon request from the Securities and Exchange Commission or a unitholder of the issuer, full information regarding the number of units purchased at each seperate price will be made available. This transaction was executed in multiple trades at prices ranging from $62.66 per unit to $64.66 per unit. The price reported above reflects the weighted average purchase price. Note that due to field restrictions in Table I, Column 4, the last decimal place does not appear. The total weighted average purchase price is actually $63.13669. Upon request from the Securities and Exchange Commission or a unitholder of the issuer, full information regarding the number of units purchased at each seperate price will be made available. /s/ Matthew D. Willcox, as Attorney-in-Fact for William E. Greehey 2011-05-12