NEW YORK, Aug 13 (Reuters) - Bill Ackman unveiled six new holdings including Netflix ( NFLX ), Visa and Mastercard ( MA ), marking the billionaire investor's biggest portfolio overhaul in years.

Ackman said on Thursday he acquired shares starting in the second quarter that will be held in his investment funds including his newest offering Pershing Square USA ( PSUS ), which was listed on the New York Stock Exchange in April.

Along with Netflix ( NFLX ), which Ackman held briefly in 2022 before selling at a loss, his funds are also investing in eye care firm Alcon, exchange operator Intercontinental Exchange and financial data provider S&P Global.

Ackman said he believes the firms' earnings are poised for strong growth, which he views as the greatest driver of investment value over time. 

Ackman, whose stock picks are closely tracked by professional investors and his 2.7 million followers on social media platform X, this year added Microsoft to the portfolio after its stock price dropped following an earnings report, arguing that the software giant would rebound when investors acknowledged its investments in artificial intelligence. Microsoft has since bounced back, thanks in part to outsize gains following its latest earnings report.

RECENT CHALLENGES

The new additions mark the biggest overhaul in years for Ackman's portfolio, which traditionally owns no more than a dozen companies.

Ackman's funds have performed strongly over the long haul but have faced challenges recently. Through July, Pershing Square USA ( PSUS ) was down 3.5% for the year and London-listed Pershing Square Holdings was down 9.2%, compared with a 13% gain for the S&P 500.

In addition to Microsoft, Ackman's portfolio includes Uber Technologies, Meta Platforms, Amazon.com, Fannie Mae and Freddie Mac, among others. 

Ackman is expected to discuss the investments on an analyst call later on Thursday.

On Friday, the new names will likely show up in 13-F filings, required by the Securities and Exchange Commission of fund managers with ownership stakes in U.S. companies at the end of the previous quarter. The reports are closely tracked by investors for hints on trends.

This has been a busy year for Ackman. The fund manager listed both his hedge fund and his new stock picking fund Pershing Square USA ( PSUS ) on the New York Stock Exchange,  exited his estimated $1.5 billion position in Universal Music Group after the company that represents Taylor Swift and Bad Bunny rejected his $65 billion takeover bid -- and turned 60 years old.

While Ackman began as one of Wall Street's most voluble activists, pushing for improved performance at companies ranging from Canadian Pacific Railway to Chipotle Mexican Grill, he prefers to be known as a value investor who has good ideas that corporate management teams want to hear about.

Four years ago Ackman said he was retiring his noisy tactics and adopting a quieter approach, characterized by cordial interactions with management teams.