Morgan Stanley PWM is the firm's ultra high net worth unit which serves clients with at least $20 million in assets.

Madrigano, who worked within the firm's New York office, generated annual revenue of between $8 and $10 million, the newswire said, citing sources with knowledge of the move.

Only a "handful of broker teams" with over $1 billion in assets under management leave any big brokerage each year, Danny Sarch, a New York-based financial services recruiter is quoted as saying in the report.

A spokesperson at Morgan Stanley confirmed Madrigano's departure, but declined to comment further when contacted by Family Wealth Report. However, regulatory filings reportedly illustrate that Madrigano has been registered with JP Morgan Securities since September 28.

Based on moves tracked by Reuters, at least 178 veteran advisors who managed over $24 billion in client assets have left the firm so far this year, with the departure of Madrigano representing one of the biggest.

"There are also additional costs with a big broker's departure, like the loss of associated revenue down the road - as top advisors generate significant money for the firm - and the cost of hiring another broker team to replace the assets lost," the report added.