This excerpt taken from the HPQ 8-K filed Nov 12, 2008.
Concentration of Credit Risk
Accounts receivable, net, from General Motors (GM) and its affiliates totaled $511 million and $342 million as of December 31, 2007 and 2006, respectively. In addition, the Company has several large contracts with major U.S. and foreign corporations, each of which may result in the Company carrying a receivable balance between $50 million and $300 million at any point in time. Other than operating receivables from GM and aforementioned contracts, concentrations of credit risk with respect to accounts receivable are generally limited due to the large number of clients forming the Companys client base and their dispersion across different industries and geographic areas.
The Company is exposed to credit risk in the event of nonperformance by counterparties to derivative contracts. Because the Company deals only with major commercial banks with high-quality credit ratings, the Company believes the risk of nonperformance by any of these counterparties is remote.