Labor Department today proposed giving money managers a broad-based exemption from federal pension law, which would let them trade securities between pension fund clients. The class exemption could save money managers hundreds of millions of dollars each year. It would apply to index funds and mathematical-model-driven portfolios, as well as to cross trades conducted as part of portfolio restructurings between passive or quantitative investment portfolios and pension funds with assets in excess of $50 million. "Cross trading can be especially important for passive and quantitative managers, whose buy and sell decisions may be triggered automatically by the mathematical models they use or changes in the indexes they track. The proposal follows consideration of comments it received from money managers and plan sponsors early last year. The Labor Department will consider permitting investment advisers to buy and sell stocks between actively managed investment portfolios of different pension fund clients after hearings next February.