The chip designer made the announcement Tuesday (September 5) as it begins marketing for the biggest flotation of the year on the U.S. stock market.

Softbank is offering 95.5 million American depository shares of the UK-based company for $47 to $51 apiece.

The valuation is lower than the $64 billion at which Softbank acquired the 25% it didn't already own in the company.

But there is still big interest in the IPO of a company whose designs power more than 99% of the world's smartphones.

Softbank will own 90.6% of Arm's ordinary shares after the offering closes, the company said. Adding that it will not receive any proceeds from the IPO.

Arm has signed up many of its major clients as investors in its IPO.

That includes a number of majors like Apple, Nvidia and Samsung.

Arm's listing is expected to excite the IPO market globally and could fuel other startups toward going public.

Any successful IPO would show the return of investor appetite for technology companies.