Hertz Global shares dropped sharply Thursday after Bill Ackman's Pershing Square Capital Management disclosed that it had exited its position in the vehicle rental company due to an equity offering announced in late June.

The fund said it had existed its position in Hertz, "which was relatively small to begin with, after they announced an equity offering that we did not think was necessary," further describing the offering as "bungled" and "unlike anything we'd seen a company do before."

Hertz stock plunged 10% to $2.52 on Thursday. The benchmark S&P 500 index was up 0.5%.

The company in June priced a public offering of roughly 37 million shares of common stock at $2.70 a share, tied to an upsized $350 million private offering of exchangeable senior notes. The stock was loaned to a share borrower for hedging, and Hertz received no direct proceeds from the sale.