Affiliated Managers Group, Inc.
A global asset management company that buys stakes in independent boutique investment firms — its "Affiliates" — while letting them keep running their own investment decisions and culture. Founded in Boston in 1993 by William J. Nutt, a former Boston Company Asset Management CEO, with backing from private equity firm TA Associates, the name reflects its model of "affiliating" with firms rather than absorbing them. Its partners have included AQR Capital Management, and it went public on the New York Stock Exchange in 1997.
Estimated from filings — the split-adjusted price range over the quarters each manager built the position. A range, not a fill price; 13F reports a quarter-end snapshot, not a trade date.