PORTLAND, Maine — A California investment firm has purchased Portland software company Certify, in a $125 million deal that combines it with other expense management software firms.

K1 Investment Management Inc., of El Segundo, California, announced the deal Tuesday to buy Certify and three other companies to create what it said will be the second largest company providing expense management software, after Concur.

Certify co-founder Robert Neveu told Mainebiz the sale price for Certify alone was near $100 million. The company has 140 employees, 90 of whom are based in Portland. They will stay in the city through the deal, Neveu said.

The company was an early investment of the Maine Venture Fund, a revolving program of the Finance Authority of Maine that on Wednesday officially got approval from voters for an injection of another $5 million.

The fund’s managing director, John Burns, told Mainebiz the fund got more than a five-fold return on its investment in Certify.

K1 will merge Certify with the companies Nexonia, ExpenseWatch and Tallie, which it said will serve about 7,500 customers. Those customers include Marketo, 1-800-Flowers, FitBit, Survey Monkey, Shopify, Century 21, HootSuite, Little Caesars, and Scribd, according to a news release from K1.