Columbia Financial (CLBK) expects to sell 167.2 million common shares at $10 each, and will acquire Northfield Bancorp (NFBK) for $580 million, the bank holding company disclosed late Thursday.

The company is presently a mutual bank, with most shares held by its mutual holding company, but with a minority of shares traded on Wall Street since 2018.

Alongside its acquisition of Northfield Bancorp at $14.25 per share, Columbia Financial will exchange all existing shares, those held in-house, by an employee stock ownership plan, or by minority shareholders, for 2.2x shares the bank's newly issued common stock.

The company expects the stock offering and merger to conclude on July 20, and at that point, to become "fully public company."

The new Columbia Financial shares are expected to start trading on the Nasdaq Global Select Market starting on July 21, still under the symbol "CLBK."