NOW that he has a stock tied to his football career, San Francisco 49ers tight end Vernon Davis is thinking more like a CEO looking out for his shareholders' interests, as well as for himself.

That's among the reasons why Davis wants the 49ers to pay him more money even though he still has two years still left on his current contract. The deal, originally signed in 2010, calls for him to make about $10 million through the National Football League's 2015 season.

"I feel like it's the right time to get an extension," Davis said in an interview with The Associated Press.

His remarks came shortly before the 49ers announced they had given their star quarterback, Colin Kaepernick, a six-year contract extension through the 2020 season for a reported $110 million.

If Davis secures a longer contract too, it will be a boon for investors who bought a stake in his football career through an unusual tracking stock from Fantex Inc.

The San Francisco company paid Davis $4 million in return for 10 per cent of his future earnings from football, commercial endorsements and other jobs that he may get during the remainder of his life because of his success in sports.

Investors who own any of the 421,000 shares of Fantex tracking stock tied to Davis will also benefit from his success through dividends and potential appreciation in the stock's price.

Davis' tracking stock climbed $1.20 Wednesday to $11.20, slightly above its initial public offering price of $10. The shares have traded as high as $12.50 since their debut on Fantex's online exchange in late April.

The IPO minted Davis, an eight-year veteran of the 49ers, as the first professional athlete to be traded like a stock.

"Everyone loves me right now," Davis said. "They just want to talk to me. They want to hug me... you get a lot of people who say, 'I've got stock in you'."

Although Fantex completed the IPO of the tracking stock five weeks ago, US securities regulations prohibited Davis from publicly discussing the investment until Wednesday.

Not long after he was able to talk about the stock, Davis said he fielded calls from 49er teammates Justin Smith, Vance McDonald and CJ Spillman inquiring about his arrangement with Fantex.

For now, business comes before football for Davis, who is considered to be among the best tight ends in the game. He caught a career-best 13 touchdowns last season.

But Davis, 30, already has played nearly three times longer than the average NFL career of three seasons. He said he wants to play "until my toes fall off" and hopes to spend his entire career with the 49ers.

The big question now is whether the 49ers will acquiesce to his demands for a longer contract. As part of his negotiating tactics, Davis skipped the 49ers' voluntary team workouts this week. His absence cost him a $200,000 bonus.

Davis will be aiming to make that money back in his contract extension, although he declined to say how much he is seeking. In an appraisal made leading up to the IPO, Fantex predicted Davis would land at least one more football contract worth $33 million.

While Davis negotiates with the 49ers, Fantex is trying to sell tracking stocks tied to the careers of two other NFL players: Buffalo Bills quarterback EJ Manuel and Cincinnati Bengals wide receiver Mohamed Sanu.