March 1 (Reuters) - SVF Investment Corp. 3, a blank-check firm backed by SoftBank Group Corp, cut the size of its initial public offering to $280 million from $350 million, a regulatory filing showed on Monday.

The special purpose acquisition company (SPAC) said it would now sell 28 million units, comprising shares and warrants, priced at $10 apiece in its IPO.

The firm, which did not give a reason for cutting the size of its IPO, said it will seek a target in the technology space.(https://bit.ly/2OdWRiJ)

SoftBank has tried to ride the mania for SPACs, with a blank-check firm backed by the Japanese conglomerate's Vision Fund's managers - SVF Investment Corp - raising $604 million earlier this year, while another, SPAC SVF Investment Corp 2, intends to raise $200 million.

A SPAC headed by SoftBank's Chief Operating Officer Marcelo Claure is also aiming to raise $200 million.

A SPAC, a shell company that raises money in an IPO and merges with a privately held company to take the latter public, has become many investors' structure of choice over the past year.

SVF Investment Corp. 3 is backed by SoftBank Investment Advisers, which oversees the company's Vision Fund, and will list on the Nasdaq.

Citigroup, UBS Investment Bank, Deutsche Bank Securities, Cantor and Mizuho Securities are underwriters for the offering. (Reporting by Sohini Podder in Bengaluru; Editing by Shailesh Kuber)