TOKYO - Japanese online financial conglomerate SBI Holdings Inc said on Saturday it has raised its stake in SBI Shinsei Bank to 53.74% from 50.04% through a tender offer as a step toward taking the midsize lender private.

The completion of the tender offer on Friday helps prepare for the expected delisting of Shinsei, allowing more flexibility in returning 349 billion yen ($2.43 billion) in public funds its predecessor bank received two decades ago in a bailout from the government, which still owns a 22.98% stake.

SBI Holdings said last month it would launch the tender offer for Shinsei, with plans to pay 2,800 yen per share, for up to 154.2 billion yen in total.

Shares of Shinsei, which closed at 2,807 yen on Friday, have remained above 2,800 yen since the announcement on speculation that some shareholders may demand a sweetened offer.

That remains far below the 7,450 yen share price the government would need to recoup the value of its loan to Shinsei.

According to Shinsei's filing, its special committee suggested the bank was worth at least 3,000 yen per share, and one independent director opposed recommending shareholders tender their shares.

Shinsei will soon begin procedures to squeeze out remaining minority shareholders except for the government. The steps include an extraordinary shareholders meeting to vote on share consolidation, which is expected to clear the required two-thirds majority, with approval from SBI and the government.

SBI aims to become Japan's fourth-largest banking group. It already owns the country's largest online brokerage, an online bank and an asset manager and has been taking shares in smaller lenders to create a nationwide network.

($1 = 143.6800 yen)

(Reporting by Satoshi Sugiyama; Editing by Jacqueline Wong and William Mallard)