Microsoft's overseas subsidiaries help fund the company's research and development efforts, and their profits are a reward for taking that risk, Sample said. Microsoft's sales overseas are growing faster than its U.S. sales, he added.

Levin questioned how a Microsoft subsidiary was taking a substantial risk in supporting the parent company's R&D. "It's all Microsoft money, isn't it?" he said.

Ezrati noted that HP employs about 80,000 people, or about a quarter of its workforce, in the U.S. and paid about $10.3 billion in U.S. salaries in 2011.

Levin questioned the HP loan program, suggesting it was highly coordinated to avoid U.S. taxes. HP has staggered the dates on which the financial quarters of the two subsidiaries end to avoid tax penalties and keep the cash flowing in, he said.

The short-term loans from HP's Belgium and Cayman Island subsidiaries are legal and amounted to a "modest" amount of the company's cash flow in recent years, Ezrati said. The U.S. Internal Revenue Service and auditor Ernst & Young have reviewed the loan program, he added.