Last month, Ackman's publicly traded Pershing Square Holdings portfolio gained 13.4%, lifting the $11.4 billion portfolio to a net gain of 62.8% in the first 11 months of 2020, according to a performance review.

Ackman recently told investors that the firm is having its best ever year and that he is "bullish" for 2021. But he warned of possible volatility ahead as the coronavirus continues to take its toll.

To guard against swings, Ackman said he put on a new hedge -- roughly one third the size of the one he put on earlier this year -- as corporate credit spreads are very tight. He earned $2.6 billion in profits from the first hedge and plowed that money back into the market, buying more of the stocks he already owns at cheaper prices.

This summer Ackman raised the biggest blank-check fund ever helping swell his firm's total assets under management -- including all hedge funds and Pershing Square Tontine Holdings -- to $17 billion.

The average hedge fund gained 1.2% through the end of October, according to Hedge Fund Research. November data is still being compiled.

(Reporting by Svea Herbst-Bayliss; Editing by Christian Schmollinger and Aurora Ellis)

By Svea Herbst-Bayliss