Billionaire John Paulson’s hedge funds dropped in August as global stocks plunged, according to a person briefed on the returns.

The firm’s merger fund fell 4.2 percent in August, said the person, who asked not to be named because the information isn’t public. The loss pared Paulson Partners’ gain to 6.5 percent in 2015.

The returns marked a setback in Paulson & Co.’s attempt to rebound from its second-worst year in 2014. The merger strategy, which comprises more than half the New York-based firm’s $19.3 billion in assets, was its bright spot in 2014 and has made money this year as some other Paulson funds struggle.

Paulson’s Advantage hedge fund, which makes bets on companies undergoing events such as bankruptcies and spinoffs, lost 4.9 percent last month, erasing 2015 gains, according to the person. The fund fell 3.6 percent this year through August.

The firm’s smaller Special Situations Fund lost 8.4 percent in August, pushing losses to almost 12 percent in 2015, the person said.

Armel Leslie, a spokesman for the firm with Peppercomm, declined to comment on the returns, which were reported earlier Thursday by Reuters.