Whether and to what extent a firm's derivatives generate tax savings is often hidden from the public and
regulators because transaction-level detail is not disclosed in financial reports. Instead, financial reporting standards
require only a brief discussion of a firm's overall hedging strategy and objectives for using derivatives (FASB, 1998,
2008). For example, throughout the 1990s, Schering-Plough Corporation participated in a “swap-and-assign” tax
shelter, which relied on interest rate swaps with foreign banks to assign interest payments to foreign subsidiaries in
exchange for an amortizable lump sum.