The headquarters of SK Group / Korea Times file

SK shieldus, a security unit of SK Telecom, is expected to raise up to 3.55 trillion won ($2.85 billion) through a planned initial public offering (IPO) next month.

The listing, set for May 19, will mark the biggest ever market debut by a security services provider, more than the value of its rival firm S-1, a security firm under Samsung Group.

"Our company integrated cybersecurity and physical security services. SK shieldus should not be compared with S-1 by one-to-one," CEO Park Jin-hyo said in an online conference.

SK shieldus, which changed its name from ADT Caps last October, currently provides security services across four main categories ― cybersecurity, convergence security, physical security, and safety and care.

Last year, the company reported 1.55 trillion won in sales, trailing behind the 2.31 trillion won recorded by S-1.

Park said the company aims to take over other security companies with higher technical skills following the IPO, and hire more personnel with expertise in platform.

SK shieldus said it set the IPO price range of 31,000 won to 38,800 won.

Credit Suisse, the lead bookrunner, Morgan Stanley, KB Securities and NH Investment and Securities have begun taking orders from investors.

Demand forecasting for domestic institutions is slated for May 3 and May 4, with that for retail investors set to take place May 9 and May 10. (Yonhap)