X0303 4 2010-10-28 0001084755 ARIBA INC ARBA 0001183230 COSTELLO KEVIN ARIBA, INC. 807 11TH AVENUE SUNNYVALE CA 94089 0 1 0 0 President Common Stock 2010-10-28 4 A 0 195001 0 A 196999 D Common Stock 2010-10-28 4 A 0 179889 0 A 376888 D This transaction reflects with respect to the number of shares reported achievement of the fiscal year 2010 performance goals applicable to the reporting person's fiscal year 2009 Performance Stock Unit award. Service-based vesting conditions continue to apply to this award. This transaction reflects with respect to the number of shares reported achievement of the fiscal year 2010 performance goals applicable to the reporting person's fiscal year 2010 Performance Stock Unit award. Service-based vesting conditions continue to apply to this award. Kevin Costello 2010-11-01