Groupon, the social buying website which recently rejected a $6- billion takeover offer from Google (Nasdaq: GOOG) has attracted the interest of some large institutional investors and is seeking to go public by the end of next year, according to a report in the New York Times.

Citing unnamed sources, the paper said that Groupon is negotiating financing deals with Fidelity Investments, T. Rowe Price (Nasdaq: TROW) and Morgan Stanley (NYSE: MS).

Moreover, according to TechCrunch.com, Groupon’s venture capital financing could reach $950-million and is expected to close in a few weeks.

The NY Times noted that after spurning Google, Groupon’s board authorized a new financing round for up to $950 million in preferred stock. The company designated more than 30 million “series G” preferred shares with a price of $31.59 each. The company also increased the number of its voting common shares to 250 million.

The Times article also noted that earlier this year Yahoo (NASDAQ: YHOO) offered to buy Groupon for about $2-billion.

The news comes as the SEC is apparently increasing regulatory scrutiny and private trading of shares in social-networking sites. The SEC has recently requested information on share transactions involving Facebook, Groupon, as well as Twitter and Zynga.

According to advisory firm Nyppex, Groupon has become a popular commodity in the secondary markets where investors can purchase shares from existing stockholders. In these private markets, Groupon’s valuation has mushroomed to $4.8-billion over just the past six months.

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