Shares of Google have nearly doubled since its initial stock offering in August, and the Web search engine's backers and founders are making millions.

The venture capital firm that backed Google in 1999 with less than $15 million distributed 5.4 million Google shares to about 200 investors in one of its funds last Tuesday, the Wall Street Journal reported, citing people familiar with the matter. The investors include 20 institutions and wealthy individuals who are now free to sell their Google shares.

Tuesday, when those shares were valued at $932 million, was the day post-IPO sales restrictions were lifted on 39 million shares held by insiders.

Last Friday, Google's co-founders and chief executive said they would sell a total of 16.6 million shares, valued at $2.8 billion, over the next year and a half. On Thursday, two vice presidents reported selling a total of 55,000 shares valued at $9.5 million.

Google sold shares during its IPO for $85. Last Friday, shares sold at $169.40 in 4 p.m. Nasdaq Stock Market composite trading. At Monday's close the stock price slipped to $165.10, sparked by reports of a big sell-off, the Journal reported.

The venture firm, Kleiner Perkins Caufield & Byers, along with the Google executives are now reaping the gains from Google, which generated such negative publicity leading up to the IPO that the company's big investors scaled back their plans. Kleiner decided against selling shares, and co-founders Larry Page and Sergey Brin, as well as CEO Eric Schmidt, all lowered the numbers of shares they planned to sell.

Now, Brin and Page each plans to sell 7.2 million shares, or roughly 19 percent of their holdings. Schmidt plans to sell about 2.2 million shares, about 15 percent of his holdings.