Google's shares surged in after hours trading on The Nasdaq Stock Market, on the company's strong third quarter financial results. Shares of the world's largest hard drive maker, Seagate Technology, soared on news reports of a takeover bid.

Google's stock rose 9.1 percent, or $49.07, to $590 in after hours trading. That's the highest level the stock has seen since it hit $597.84 during midday trading on April 15.

The company reported its third quarter net income increased 32 percent year-on-year to $2.17 billion, while its revenue rose 23 percent to $7.29 billion. Both figures beat analysts estimates.

Google executives said they saw strength in every major product area during the third quarter. Google's stock was the third most actively traded by volume on the Nasdaq after hours on Thursday.

Seagate Technology saw its stock rise 20.7 percent, or $2.63, to $15.32 in after hours trading amid reports its in talk with private equity firms to be bought out and taken private. Citing unidentified sources, Bloomberg News said Seagate's discussions include private equity firms TPG Capital and KKR & Co. Reuters reported that Seagate confirmed the talks and that TPG is definitely involved.

The last time Seagate's stock was higher than Thursday was on June 21, when it hit $15.63 in midday trading. The publicly traded company was the second most actively traded stock by volume in after market trading on Thursday.

A company that lists its stock on public stock markets is considered a public company, while a private company is one in which its stock is held by private investors and not traded on public markets. One big difference between the two is in financial reporting. In the US, private companies do not have to file quarterly earnings reports and other reports required by the Securities and Exchange Commission. Companies with publicly traded stock have to publicly file numerous reports to the SEC keep up with legal requirements.