Ant Financial, an affiliate of billionaire Jack Ma's Alibaba Group Holdings Ltd.’s (BABA), has become the latest high profile investor to express an interest in buying a big stake in Brazilian fintech firm StoneCo Ltd ahead of its initial public offering (IPO) next Thursday.

The Brazilian card processor, which is offering up to 54.9 million shares and could raise as much as $1.26 billion if it prices at the top of its range, said in a securities filing that Ant Financial has committed to invest $100 million in its IPO, reported Bloomberg.

Ant Financial’s backing represents another huge win for StoneCo. The Brazilian firm has already secured the support of other highly-regarded heavyweights, including Madrone Capital Partners and billionaire Jorge Paulo Lemann’s private equity firm 3G Capital Inc., and is now also reportedly attracting interest from Warren Buffett, one of the world’s most famous investors.

Berkshire Hathaway Inc. (BRK.B) is believed to be willing to buy up to 14.2 million Class A shares ahead of StoneCo’s Nasdaq listing, according to Bloomberg and Reuters. Bloomberg also reported that Madrone, which is backed by the heirs to the Walmart Inc. (WMT) fortune and currently holds a 9.3% stake in the Brazilian firm, is keen to purchase an additional 2.4 million shares prior to the offering.

Brazilian Payment Firms All The Rage

Widespread interest in StoneCo’s IPO from wealthy, highly influential international investors should perhaps come as little surprise. PagSeguro Digital Ltd. (PAGS), another Brazilian payment firm, raised about $2.6 billion on the New York Stock Exchange in January, making it the biggest IPO since Snap Inc. (SNAP) listed its shares in 2016. 

Meanwhile, earlier this month, Alibaba’s Chinese rival Tencent Holdings Ltd. (TCEHY) acquired a minority stake in Brazilian credit-card startup Nubank. This move once again emphasized the excitement surrounding the country’s fintech sector, which is being buoyed by data showing that only two-thirds of families’ consumption in Brazil is paid for in cash.

Goldman Sachs reacted to a surge in interest in Brazilian payment firms by warning that the market is rapidly becoming swamped with competition. The investment bank estimated there were 210 different fintech firms in Brazil last year, up from 54 at the beginning of 2015.