March 7 (Bloomberg) -- Clearwire Corp., a wireless-Internet company founded by mobile-phone pioneer Craig McCaw, plans to raise up to $500 million in an initial share sale today, gauging appetite for new U.S. issues after last week's stock plunge.

The firm, based in Kirkland, Washington, plans to sell 20 million shares for $23 to $25 each. The underwriters have the option to sell an additional 3 million shares if demand warrants.

The sale would be the largest U.S. initial public offering since Feb. 27, when the Standard & Poor's 500 Index and the Dow Jones Industrial Average fell the most in four years. Both dropped more than 3 percent, capping a five-day slide triggered by concern share prices globally had risen too high.

``It's a big test,'' said Ben Holmes, publisher of Boulder, Colorado-based Morningnotes.com. ``Since we've had no activity last week and really none this week, we have no proof of what type of market we're in until we see the first couple of deals.''

Clearwire, founded by McCaw in 2003 to build a worldwide wireless network, filed for an IPO in May and withdrew the offer in July after raising $900 million from investors including Intel Corp. and Motorola Inc.

At least four other companies plan to offer shares this week, including Shanghai-based Xinhua Finance Media Ltd., a provider of financial news and data on China's markets; and Columbia, Maryland-based Sourcefire Inc., an open source network security provider.

Cancer-drug maker OncoGenex Technologies Inc. postponed an initial share sale, while Liquidity Services Inc., a Washington- based online auction site for wholesale goods, shelved a secondary offering, according to Bloomberg data. Both Vancouver- based OncoGenex and Liquidity attributed delays to ``market conditions.''

2006 Sales Tripled

Clearwire's big names may attract interest in the offering even amid the company's mounting losses, said David Menlow, who tracks the market at Millburn, New Jersey-based IPOFinancial.com.

The company has lost money every year since it began. In the period ended Dec. 31, Clearwire had a net loss of $284.2 million, compared with a loss of $140 million in 2005, according to a Feb. 20 regulatory filing. Sales last year tripled to $100.2 million and the company had 206,200 subscribers as of Dec. 31.

Clearwire spokeswoman Teresa Fausti didn't return a call seeking comment.

``Clearwire has heavy expenses in terms of building the business, building the network and acquiring customers,'' said Brad Williams, a technology analyst at MTB Investment Advisors in Baltimore, which manages $11 billion. ``It's going to take a while for them to prove themselves in terms of what their profitability model will look like.'' MTB doesn't actively participate in IPOs.

Seeking Expansion

Clearwire is raising money to expand its wireless network. The company may gain 10 million subscribers and lift its sales to $5 billion in 2012, said Walter Piecyk, an analyst at Pali Research in New York. He estimates the company will become profitable in 2011.

``Customers are interested in having an alternative to broadband access in their homes or on the road,'' Piecyk, who won't participate in the offering, said in an interview. ``The IPO is attractively valued and we expect it to be successful,'' he said. Demand for the shares will probably exceed what's available, he added.

The stock is worth $35 now and may reach $75 in 2012, Piecyk estimates. The IPO may value Clearwire at more than $4 billion, he said.

The wireless provider has a chance to lure subscribers by offering lower prices than fixed-line Internet service firms and mobile-phone companies offering wireless data service, he said. The company competes with Verizon Communications Inc., AT&T Inc. and Sprint Nextel Corp.

McCaw's Return

McCaw aims to commercialize a high-speed wireless Web access technology called WiMax that broadcasts Internet signals as far as 30 miles. Santa Clara, California-based Intel, the world's largest computer-chip maker, and Schaumburg, Illinois-based Motorola, the second-biggest cell-phone maker, are backing that technology to gain faster Web access for mobile phones and laptops.

The offering would mark McCaw's return to the public markets where he became a billionaire in the 1990s after putting together the first U.S.-wide cellular telephone network. He sold the company, McCaw Cellular Communications, to AT&T Corp. in 1994 for $11.5 billion.

Clearwire plans to have two classes of stock, a format used by some companies to ensure that founders keep control. Class A shares, which will be offered to the public, will have one vote each. Class B shares will have 10 votes. McCaw controls 52 percent of the votes, according to the filing.

The shares will trade on the Nasdaq Global Market under the ticker CLWR. Merrill Lynch & Co., Morgan Stanley and JPMorgan Chase & Co. are leading the sale with assistance from seven other banks.

To contact the reporters on this story: Elizabeth Hester in New York at ehester@bloomberg.net; Ville Heiskanen in New York at vheiskanen@bloomberg.net

Last Updated: March 7, 2007 11:08 EST