Digital payments startup Stripe, begun back in 2000 by a pair of Irish brothers, has just raised new funding that values the company at just over $9 billion—and incidentally makes its founders the youngest billionaires in Ireland. In all, $150 million in new capital was raised.

This brings the company’s total equity funding up to over $450 million, in addition to its skyrocketing valuation. Both are factors which raise the big question: will Stripe be filing for an IPO in the near future?

The company’s new funding comes at a time when venture capitalists have been somewhat skittish about parking their money in fintech, with funding for many sectors slowing to a trickle of what it was just two years ago—Stripe’s sharp rise in valuation, nearly double its previous $5 billion mark, falls decisively against the current curve for fintech startups. Stripe is now the most valuable fintech startup in the U.S. — more than the Dutch payments startup Adyen, but less than the Hangzhou-China-based Ant Financial, which operates Alipay.

Ant is also reportedly considering an IPO — but there are plenty of reasons for companies to stay private as well.

As more and more consumers flock to online and mobile commerce — just look at the sales reported on Black Friday — secure and speedy online payments, such as Stripe provides, are a necessity. Square, which went public last year after a $6 billion valuation, has steadily been growing — seems like a pretty decent time to file an IPO.

In addition to the new funding round, the leaders of which were Alphabet Inc’s investment arm, CapitalG, and VC firm General Catalyst Partners, Stripe will also reportedly be receiving a $250 million line of credit from banks that include JP Morgan, Goldman Sachs, and Morgan Stanley—all of which recently made headlines for choosing not to invest in the R3 blockchain consortium. (Even blockchain is suffering from a funding slump, according to recent data.)

Stripe’s technology has always intrigued the fintech world. Like Square, the company processes transactions for its clients, though it makes the bulk of its revenue through taking a bite out of online transactions, whereas Square makes its money from transactions completed primarily at the physical point of sale, and increasingly through loans to its businesses.