Shares of alternative asset managers with exposure to energy companies tumbled as U.S. stocks plunged broadly and oil had its biggest drop in a generation. A battle for market share between Saudi Arabia and Russia is threatening to boost crude supply just as the coronavirus is spurring the first decline in demand since 2009.

Blackstone Group Inc. fell 13% in New York, its biggest one-day drop since November 2008. Apollo Global Management Inc. sank 16%, its worst day since going public in 2011. Carlyle Group Inc. and KKR & Co. both dropped 12%.

The stock rout threatening the 11-year bull market is taking a big toll on the financial sector and private equity firms are among the hardest hit even though they typically invest with a long-term horizon, often setting up their funds with 10-year life spans. In the last few years, firms including Blackstone and Carlyle have raised billion of dollars for energy deals as they saw potential value in oil and gas companies that were already slumping.

The impact on private equity firms could spread beyond energy investments to other parts of the business, according to Devin Ryan, an analyst at JMP Securities LLC.

“When energy companies experience pressure, that tends to create some stress in credit markets more broadly,” Ryan said.

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Blackstone, whose holdings in the sector include Cheniere Energy Partners LP, said on a conference call with investors in October that energy investments accounted for about 15% of the credit group and almost 10% of the firm’s total portfolio.

Energy makes up about 4% of Apollo’s private equity and credit portfolio, Martin Kelly, chief financial officer and co-chief operating officer, said on a Jan. 30 earnings call. Energy losses muted gains in the firm’s private equity portfolio during the fourth quarter, with writedowns tied to “a very, very poor price environment” for oil and gas, he said.

One of the firm’s larger public holdings is Talos Energy Inc., which tumbled 31% on Monday after postponing its March 12 analyst and investor event for safety reasons amid the virus outbreak.

Any long-term impact on the energy industry could hurt Neuberger Berman’s Dyal Capital Partners, which holds stakes in six private equity firms with a focus on energy, including Energy Capital Partners, EnCap Investments and Quantum Energy Partners.

Distress in the market could also lead to more deal opportunities for the firms at a time when transaction prices remain near all-time highs.

“You have to remember that Blackstone is sitting on $150 billion of dry powder and they may find attractive opportunities in a dislocation,” said Gerald O’Hara, an analyst at Jefferies Group LLC. “The fundamental business model of these firms is set up to better weather this kind of scenario than many other financial services firms.”