Banking officials decry FAS 107 as burdensome. (Financial Accounting Standards Board Rule 107)

A new accounting rule requiring all companies to disclose the fair market value of financial assets is being criticized by banking officials as an unnecessary burden on financial institutions.

These assets, which include cash, investment securities and loan portfolios, are currently included on balance sheets on a "cost basis," or by fixed value. The new rule requires firms to estimate the current market value of the assets based on outside economic factors such as volatility in interest or exchange rates.

Financial Accounting Standards Board Rule 107 is applicable to all types of companies, but it significantly increases the amount of information on the balance sheets of banks and financial service companies, since they primarily deal in these types of financial instruments.

George Clarke, vice president and controller at UST Corp., the holding company of U.S. Trust Co. in Boston, said the accounting rule could help create an information overload that …