(Reuters) - Securities custody and clearing firm Apex Clearing Corp is in talks with blank-check firm Northern Star Investment Corp II to be taken public, Bloomberg News reported on Friday. Northern Star is backed by Jon Ledecky, who is the majority owner of the NHL team, New York Islanders. The deal is expected to value the combined entity at around $5 billion, Bloomberg reported bloom.bg/3b39iFU, citing people familiar with the matter. Shares of Northern Star were up 4% at $11 in early trading after the report. Dallas, Texas-based Apex is owned by fintech firm Peak6 Investments LLC and its customers include Firstrade Securities Inc and Social Finance Inc (SoFi), Apex’s website showed. It was the clearing house for trading app Robinhood until it launched its own trade-clearing system in 2018. Clearing houses moved into the spotlight recently when Robinhood’s clearing houses asked the online broker to provide more collateral against the trades flowing through its platform, egged on by the Reddit-fueled frenzy that set certain stock prices to skyrocket. Northern Star, the special purpose acquisition company (SPAC), is also led by former Cosmopolitan magazine editor-in-chief Joanna Coles. It raised $400 million in an initial public offering last month. SPACs - shell companies which raise funds through an IPO to take a private company public - have become an immensely popular route for companies looking to enter the public market as it allows them to sidestep the struggles attached to an IPO and ensures more stability in terms of valuation.