REPORT: Bill Ackman has fired some staff members

Manuel Balce Ceneta/AP

Bill Ackman's hedge fund has laid off eight lower-level staffers, The Wall Street Journal's David Benoit just reported, citing people familiar with the matter.

The cuts, mostly of back-office workers, amount to more than 10% of Pershing Square Capital Management's staff, according to The Journal.

The layoffs were unrelated to the hedge fund's recent poor performance and instead were due to the firm's ability to automate back-office tasks like filling out investor forms, according to the report.

A Pershing Square spokesman declined to comment.

Pershing Square has faced a decline in performance this year as a big investment in Valeant Pharmaceuticals soured. Ackman has said he expects the investment to rebound.

Pershing Square's publicly traded fund, which mimics the private hedge fund, is down 20.9% this year through June 21. The New York activist firm in 2015 had its worst year ever, slumping 20%.

With performance declines, assets under management have also dropped. The firm managed $20.2 billion at its peak last July, a number that fell to about $12 billion in May.

Pershing Square's structure has helped the firm retain assets by preventing a run on its reserves during rough times. Outside investors can pull only one-eighth of their capital every quarter, for example. And the firm's $4 billion closed-end fund is another source of permanent capital, since investors have to sell their shares to redeem.

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