What happened

Less than a week after UP Fintech Holding (NASDAQ:TIGR) stock sold off in response to Q1 earnings, shares of the Chinese online brokerage are rebounding nicely today -- up 10.5% as of 1:15 p.m. EDT -- on news that the company has a big fan in the United States.

That would be Greenwich, Connecticut-based Interactive Brokers (NASDAQ:IBKR).

100-yuan bills fanned out atop a business newspaper

Image source: Getty Images.

So what

In a Schedule 13D filing last night with the Securities and Exchange Commission, a company related to Interactive Brokers -- IB Global Investments LLC (IBGI) -- disclosed that with UP Fintech's recent initial public offering, IBGI converted its 137,635,322 Series B-3 preferred shares, purchased last year, into an equivalent number of Class A ordinary shares of UP Fintech. In addition, IBGI purchased 13,125,000 more shares of common stock in UP Fintech "in a concurrent private placement transaction for $7 million."

As a result, IBGI now owns nearly 150.8 million shares of UP Fintech. That amounts to 7.6% of Class A ordinary shares, according to the filing. 

It's clear that IBGI seems to think that UP Fintech is a worthy investment. It appears that, based on that assessment, other investors are buying in today.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.