BOSTON (Reuters) - William Ackman is cutting almost a fifth of staff and looking to lower his public profile as he seeks to turn around Pershing Square Capital Management after three straight years of losses, people familiar with the move told Reuters on Monday.

FILE PHOTO: Bill Ackman, chief executive officer and portfolio manager at Pershing Square Capital Management, speaks during the SALT conference in Las Vegas, Nevada, U.S. May 18, 2017. REUTERS/Richard Brian/File Photo

The billionaire hedge fund manager, who recently suffered big losses on Valeant Pharmaceuticals International Inc VRX.TO and Herbalife Ltd HLF.N and lost a proxy fight with Automatic Data Processing Inc ADP.O, will spend more time investing and stop being the firm's No. 1 marketer, the people said.

The first step in turning around Pershing Square is laying off 10 people, shrinking the firm to 46 employees from 56, to oversee the roughly $9 billion in assets the firm manages for clients, the people said.

That is about half the assets he had at Pershing Square’s peak in 2015. Most of the reduction will involve back-office employees, although one investment team member is also leaving.

Ackman also plans to go silent, at least for awhile, the people said, a major change in style for one of Wall Street’s most voluble investors.

The 51-year-old hedge fund manager, who made his name with winning bets on Allergan Plc AGN.N, Canadian Pacific Railway Ltd CP.TO and others, became one of the world's most visible activist investors through lengthy public appearances. He hosted hours-long conferences in Manhattan to answer every question about his short bet against Herbalife and his plan for drugmaker Valeant to buy rival Allergan.

Ackman plans to curtail all of his own marketing and public relations meetings associated with running a big hedge fund, said the people familiar with the matter, who were not authorized to discuss the changes publicly.

Instead, Ben Hakim, a partner who joined Pershing Square in 2012, will do the traveling and bulk of talking to clients. Ackman will stay in the office, concentrating on financial analysis.

Pershing Square spokesman Francis McGill declined to comment.

DINNER DATE

Ackman plans to announce the personnel changes and new direction on Thursday at the firm’s annual client dinner at the New York Public Library.

That dinner, and another similar event in London, will become the once-a-year chance for pension funds, endowments and wealthy investors to see and hear Ackman discuss performance and lay out his strategy, the people said. This time, Ackman will detail how his private funds lost between 1.6 percent and 3.2 percent in 2017.

For months, Ackman has been promising a comeback. In the first few weeks of this year, Pershing Square’s funds are up about 2 percent while the stock market has been setting new records, with the S&P 500 Index gaining more than 5 percent year-to-date.

As Ackman's fame and investing prowess grew over the years with successful bets on Canadian Pacific, General Growth Properties and Air Products and Chemicals Inc APD.N, Pershing Square's assets also grew. But investors traditionally pull 10 percent to 15 percent of capital from a hedge fund every year, making it more difficult for larger firms to keep replacing assets.

New clients often demand an audience with the boss, but Ackman has told people he is putting an end to that practice. He still plans to communicate with investors through letters and quarterly calls, and occasionally make public statements about investments.

Hakim and Pershing’s investor relations team will be available to handle day-to-day queries that Ackman previously spent a significant amount of time on.

In making the changes, Ackman wants the firm to operate more as it did in 2012, when he won a big proxy contest at Canadian Pacific, people familiar with the matter said. Pershing Square then employed 46 people and managed $11 billion. The firm’s staff peaked at 70 people in 2016.

One member of the investment team is among the job cuts, people familiar with the matter said.

David Klafter, a senior lawyer at the firm, will join the investment team to handle legal matters associated with the firm’s bets, which usually total only about a dozen.

Pershing Square’s investment team has historically had between eight and 10 members and will stay at its current size of 10 people, the people said.

Ackman also laid off his driver, saying he can walk or take the subway to his Midtown Manhattan office, the people familiar with the matter said. The staff were told the news of the layoffs late last week.