NEW YORK ( TheStreet) -- Zynga ( ZNGA) was a major gainer in premarket trading on Thursday, rising 16.96% to $2.49 after the company's third-quarter results late on Wednesday. Hot on the heels of the third-quarter top- and bottom- line beat from key partner Facebook ( FB) earlier this week, Zynga reported revenue that beat analysts' estimates. The San Francisco-based firm reported sales of $317 million, above analysts' forecasts of $256.4 million. Excluding items, the social gamer broke even on a per-share basis, in line with analysts' estimates. Zynga also forecast 2012 earnings between 2 cents and 3 cents a share and announced a $200 million share buyback. The company was the most active premarket Nasdaq stock on share volume of 952,907. Facebook was also up Thursday, rising 1.59% to $23.60 on share volume of 75,955. Symantec ( SYMC) was another gainer, rising 9.44% to $19.02 after skipping past analysts' second-quarter estimates on Wednesday. The security software specialist brought in revenue of $1.7 billion, an increase of 1% on the same period last year, or a 5% hike adjusted for the effects of currency. Analysts surveyed by Thomson Reuters were looking for sales of $1.66 billion. Excluding items, Symantec earned 45 cents a share, up from 39 cents a share in the year-ago quarter, and comfortably above analysts' forecast of 38 cents a share. "I am pleased with the team's results and progress made this quarter. We delivered solid results during the first quarter of a significant transition for the company," wrote Symantec CEO Steve Bennett, in a statement released after market close. "While focused on running the company, the team is also hard at work building a strategy and operational plan to deliver greater than 5 percent organic growth and 30 percent operating margins on a sustainable basis within the next two-to-three years." F5 Networks ( FFIV), however, was a laggard after reporting its fiscal fourth-quarter results on Wednesday, which were weighed down by slowing growth in the second half of the year. Shares of the networking gear maker plunged 10.69% to $83.35 in premarket trading. Microsoft ( MSFT), which hosts its Windows 8 launch event in New York on Thursday, crept up 0.85% to $28.14. Apple ( AAPL) shares rose 0.41% to $619.34 ahead of the company's fourth-quarter results after market close Thursday. TheStreet will be live-blogging Apple's earnings announcement from 3:45 p.m. EDT. --Written by James Rogers in New York. Follow @jamesjrogers >To submit a news tip, send an email to: email@example.com.