Want a Piece of a Star Athlete? Now, You Really Can Buy One.

Eric Gay/Associated Press

Imagine having acquired a financial interest in LeBron James, Peyton Manning or Roger Federer early in their careers.

A new company wants to make this fantasy a reality for the next generation of superstars.

On Thursday, Fantex Holdings will announce the opening of a marketplace for investors to buy and sell interests in professional athletes. The start-up, backed by prominent executives from Silicon Valley, Wall Street and the sports world, plans to create stocks tied to the value and performance of an athlete's brand.

It will have its debut with an initial public offering for a minority stake in Arian Foster, the Pro Bowl running back of the Houston Texans. Buying shares in the deal will give investors an interest in a stock linked to Mr. Foster's future economic success, which includes the value of his playing contracts, endorsements and appearance fees.

Buck French, the company's co-founder and chief executive, said Fantex hoped to sign additional players in football and other sports, as well as expand into other talent areas like pop singers and Hollywood actors.

'Fantex is bringing sports and business together in a way never previously thought possible,' Mr. French said. 'We have built a powerful platform to help build the brands of athletes and celebrities.'

For now, the offering is trying to capitalize on the immense popularity of the National Football League and fantasy football, in which fans pick individual players and get points for touchdowns, interceptions and other notable plays.

Fantex calls to mind other unusual investments tied to celebrities. In the late 1990s, a financier created 'Bowie Bonds,' a small bond deal that paid interest from the current and future revenue of 25 albums by the rock musician David Bowie. The brokerage Cantor Fitzgerald runs the Hollywood Stock Exchange, a marketplace for bets on the fortunes of movies and their stars. But a real Hollywood exchange has never gotten off the ground, and bettors only use play money.

Nothing about Fantex is make believe. As of Thursday, investors can register with the company, finance their accounts with cash and place orders for shares in the Foster I.P.O. The offering plans to sell about $10.5 million worth of stock, representing a 20 percent interest in Mr. Foster's future brand income. Mr. Foster will pocket $10 million; the balance will cover the costs of the deal.

Unlike many esoteric Wall Street investments that are available only to so-called high-net-worth individuals, the Fantex offering is available to United States residents 18 years and older, with a minimum investment of $50. There are some restrictions. For instance, investors with annual incomes of $50,000 to $100,000 may only invest up to $7,500 in the offering. Individual state securities laws might also place further limits and who can invest, Mr. French said.

Fantex will market the Foster I.P.O. in the coming weeks, offering 1.06 million shares at $10 a share. No one can own more than 1 percent of the offering, ensuring that it is available to a wide number of investors. If demand is less than the number of shares being offered, Fantex may cancel the deal.

But if it proves successful, Mr. Foster's tracking stock will then trade exclusively on an exchange operated by Fantex. Presumably, the tracking stock will increase in value if Mr. Foster raises his earnings potential with standout on-the-field performance or increased corporate sponsorships. Then, the investor can try to sell his shares at a higher price. Fantex will make a 1 percent commission from both the buyer and seller on the trades.

Mr. French, the company's chief executive, demurred when asked to predict how the stock might behave in a secondary market.

'We don't know how it will trade,' Mr. French said.

Mr. French, a graduate of West Point and Harvard Business School, made a fortune during the dot-com boom when, in 2000, he sold OnLink, a software company he founded and ran, to Siebel Systems for about $600 million. One of his Fantex co-founders, David M. Beirne, was a general partner at Benchmark Capital, the venture capital firm that was one of eBay's earliest investors.

Mr. French said it was Mr. Beirne who conceived of the Fantex concept more than a decade ago when he backed MVP.com, a sports e-commerce venture. At MVP.com, Mr. Beirne worked closely with several pro athletes, including John Elway, the former Denver Broncos quarterback and a member of Fantex's board of directors.

'Fantex represents a powerful new opportunity for professional athletes, and I wish it were available during my playing days,' Mr. Elway said in a statement.

Wall Street executives have also joined the start-up. Fantex's president is John Rodin, co-president of the hedge fund Glenview Capital Management and a Goldman Sachs alumnus. Its chief technology officer is Joshua S. Levine, a former senior executive at E*Trade, Deutsche Bank and Morgan Stanley.

Fantex, based in San Francisco, has already jumped through several legal hoops. The company has filed its registration statement for the I.P.O. with the Securities and Exchange Commission. It has also established Fantex Brokerage Services, a registered broker-dealer trading platform that will serve as the marketplace of buying and selling the tracking shares of athletes.

It is unclear what the N.F.L. or any of the professional sports leagues will think of Fantex. Mr. French said that while the company had discussed its business model with the N.F.L. players' union, it had not spoken with league officials. In Fantex's view, Mr. French said, the N.F.L. has no say over whether a player can sell a stake in his brand to outside investors.

Also not known is whether there are other athletes on the sidelines awaiting their turn at an I.P.O., and Mr. French declined to say. On one hand, athletes and their agents could view Fantex as a compelling proposition, as it would allow the athletes to receive an upfront payment by giving up a certain percentage of their future earnings. Such a payment could act as a hedge against a career-ending injury or a performance slump.

But advisers could counsel against trading a piece of their future earnings for a large payment, as professional athletes are notorious for squandering money with their spendthrift ways.

Fantex could do worse with Mr. Foster as its first offering. He is one of the top running backs in the league, popular not only with Houston Texans fans but also with fantasy football players. In recent years, Mr. Foster has been a top draft pick in fantasy leagues because of his potential for big touchdown totals and yardage.

A fifth-year veteran from the University of Tennessee, Mr. Foster, 27, has led all running backs in rushing touchdowns in two of the last three seasons, while racking up well over 1,000 yards each year. In March 2012, Houston was said to sign Mr. Foster to a contract worth up to $43.5 million over five years. Half Mexican-American, half black, Mr. Foster is a crowd favorite and media darling who trumpets his passions for poetry and yoga. When he scores, he clasps his hands together and bows a 'namaste' pose.

'We see Arian as a unique, multidimensional individual, a trailblazer,' Mr. French said.

Yet during the first six weeks of this season, Mr. Foster's production has flagged and he has scored just one rushing touchdown. There had been some uncertainly surrounding Mr. Foster coming into the year, as he was hampered with calf and back injuries during the off-season. In February, he also had to bat down rumors of a heart condition.

Those issues underscore the risk of betting on Mr. Foster's brand, or that of any professional athletes, especially N.F.L. players.

Unlike some other sports, N.F.L. contracts often are not fully guaranteed, meaning players are often cut and forced to find a new team, sometimes for a lesser contract. Injuries are frequent, unpredictable and can severely crimp the value of a player's brand. The shelf life of an N.F.L. player can be short. An injury or a few subpar games can land a player on the bench, making way for a teammate to fill the void on the field. Sometimes, when a job is lost, it is difficult to find a new one.

For investors, the long-term outlook for a player will be difficult to handicap. And if a player's fortunes suffer and the tracking stock declines, there will be no rescue financing from a private equity firm - or an investor like Warren E. Buffett - to stabilize the share price.

And unlike a stockholder of a public company, investors have no corporate governance rights. There are no plans to hold annual meetings with the athlete, or quarterly conference calls to discuss how that hamstring tear is healing, or how negotiations with Nike are coming along.

'The offering is highly speculative and the securities involve a high degree of risk,' Fantex says in its marketing materials. 'Investing in a Fantex Inc. tracking stock should only be considered by persons who can afford the loss of their entire investment.'