He managed a portfolio worth more than £1.5 billion.

Newman, who managed a portfolio of technology stocks for Diamondback, could not be reached for comment at his suburban Boston home this week.

Most recently, d'Oelsnitz was a managing director at Pan American Financial Resources, where he managed a portfolio of funds in real estate, infrastructure and debt.

In that post, Sloan managed a portfolio of $200 billion in assets and 440 offices in 40 U.S. states, Canada, London and in Asia.