Nathan Most, known as the "father of the exchange-traded funds," died Dec. 3 in San Mateo, Calif. He was 90. Mr. Most was chairman, president and CEO of iShares Inc. and iShares Trust, both units of Barclays Global Investors, from 2000 to 2002. He was also a trustee and a consultant to BGI. "Besides serving as the first chairman of the iShares board, he was a positive influence on so many people," said Lance Berg, BGI spokesman. In the early '90s, Mr. Most helped to pioneer the Standard & Poor's Depositary Receipt, which allowed investors to trade the entire S&P 500 index as a single AMEX stock — a prototype that spawned the fast-growing ETF industry. In lieu of flowers, donations may be made to Mission Hospice of San Mateo County, 151 W. 20th Ave., San Mateo, CA 94403.