FAIRPORT, N.Y. , Sept. 13, 2021 /PRNewswire/ -- Manning & Napier, Inc. (NYSE: MN), (" Manning & Napier " or "the Company") today reported preliminary assets under management ("AUM") as of August 31, 2021 of $22.7 billion , compared with $22.5 billion at July 31, 2021 , and $22.3 billion at June