Marathon Acquisition's upcoming IPO is a risky run for investors. Marathon, a so-called blank-check company founded by Wall Street veteran Michael Gross, is expected to price a $300 million stock offering on Tuesday night, according to sources close to the deal. The initial public offering is just another example of Wall Street's seemingly endless infatuation with blank checks -- fledgling companies in search of a business plan. The deal is largely dependent on the resume of Marathon's sponsor, Gross, one of the founders of the $10 billion private equity outfit Apollo Management. Marathon is being pitched to investors as a chance to place a bet on Gross' reputation as one of Wall Street's master wheeler-dealers. But some on Wall Street are becoming increasingly skeptical of blank-check deals and the willingness of investors to blindly hand cash to management with a theoretical "trust us" strategy. "People are so completely oblivious, yet we'll give you all this money," says David Menlow, president of IPOFinancial.com. "I don't care how good the principals are, there is still a risk of investing into dogs." Over the past three years, Wall Street has breathed new life into the blank-check model by pitching deals to hedge funds as a relatively safe way to invest in private equity. The blank-check company takes its publicly raised cash and tries to find something to buy with it. If the company can't find a deal within 18 months, the investors get most of their money back.