Alldis joined Legg Mason in 2005 and had been a director since 2007.
Meanwhile Robert Shearman has been appointed to the board with effect from 11 July.
Shearman is a managing director and head of international product at Legg Mason Investments (Europe). Shearman joined Legg Mason in 2005 and currently leads all research, strategy and the development of mutual fund product ranges.
Shearman was at Citigroup Asset Management and Morley Fund Management performing similar roles before he joined Legg Mason. He has spent over 20 years working in product development in total.
