(Reuters) Latin American and Spanish call center operator Atento SA, owned by private equity firm Bain Capital Partners LLC, said it expected its initial public offering to be priced $19-$22 per share, valuing the company at up to US$1.60b.

At the top end of the expected price range, the IPO is likely to raise about $321.8 million.

Bain Capital bought Atento Group from Telefonica SA , Europe’s biggest telecom operator by revenue, in 2012 for about 1 billion euros ($1.3 billion), including debt.

In the offering of about 14.6 million shares, Atento is selling 4.1 million shares and stockholder Atalaya PikCo SCA the rest.

Bain Capital’s stake in Atento will drop to 75.3 percent from 98.2 percent if the underwriters fully exercise their option.

Atento, which runs helpdesks, back offices and other service desks, has about 153,000 employees, with about half of them in Brazil.

The company was formed in 1999 as a spinoff of Telefonica’s call center business in Spain, Peru and Chile.

Reuters reported last week, citing sources, that Atento was likely to launch its offering as early as this week.

Atento’s loss attributable to shareholders widened to $24.3 million in the six months ended June from $23.1 million, a year earlier. Revenue dropped about 1.2 percent to $1.15 billion.