Arguments that they lack transparency or may be subject to manipulation are largely off base. : (Bloomberg Opinion) -- Last month, the New York Times ran an op-ed that suggested index funds may not be as transparent as they seem or should be, or as well-regulated. The article, written by a Securities and Exchange Commission member and a University of California - Berkeley law professor also implied that the indexes on which the funds are based could be subject to manipulation and other abuses. I heartily endorse any sentiment that mandates more timely and detailed disclosure of index-fund holdings.