SPB is hoping to raise $150 million in an IPO on its own bourse before the end of this year ahead of a larger U.S. listing in the first half of 2022, two people familiar with the matter told Reuters on Thursday.

The Moscow Exchange said NP RTS, which owns 16.5% of SPB and distributes its market data, had not responded to multiple requests for the data to be shared.

"After unsuccessful attempts to obtain market data from NP RTS, the Moscow Exchange was forced to take extreme measures and file a lawsuit," the bourse said in a statement, after the Moscow Arbitration Court published documents concerning the case on Thursday.

"Unfortunately, today we see no other option for upholding our rights and the interests of Russian exchange market participants."

A hearing has been set for Oct. 28, the court documents showed.

SPB Exchange said it was looking into the matter, but gave no further comment.

SPB, which specialises in foreign securities, had a trading volume in September of $26.8 billion, up 47.8% year-on-year. The Moscow Exchange's stocks section had a volume of around $39 billion that month.

(Reporting by Andrey Ostroukh; Writing by Alexander Marrow; Editing by Kevin Liffey)