Apple, Zynga, Sourcefire: Tech Winners & Losers

NEW YORK ( TheStreet) -- Shares of Apple ( AAPL) ticked down 1.35% to $657.83 as the world marked the one-year anniversary of the death of former CEO Steve Jobs.

Apple posted a video remembering the life and times of its legendary co-founder on the front page of its Web site, while CEO Tim Cook wrote a letter expressing what Steve Jobs meant to the company, as well as the world.

Under Cook, Apple has released several new products, including the iPhone 4S and iPhone 5, the new iPad, and a new line of Macs with Retina Display. He has also turned Apple into the most valuable company in the world. Shares have gained 62.5% year-to-date.

Zynga ( Z) shares plunged 18.11% to $2.31 after the company lowered its 2012 guidance for the second time in four months.

For the full year, Zynga now expects bookings between $1.085 billion and $1.1 billion, down from a previous range of $1.15 billion and $1.225 billion. Adjusted EBITDA is expected to be between $147 million and $162 million, down from a previous forecast of $180 million to $250 million.

Zynga also announced preliminary third-quarter sales between $300 million and $305 million. Excluding items, the company expects a result between breakeven and a loss of 1 cent a share. Zynga said it take a write-down between $85 million and $95 million associated with its purchase of OMGPOP earlier this year. Analysts polled by Thomson Reuters were looking for the San Francisco-based game developer to report break-even earnings on $275.9 million in revenue for the third quarter.

Shares of Sourcefire ( FIRE) rose 2.87% to $48.74 as investors appear to be focusing on news earlier in the week that the company's third-quarter results will be better-than-expected.

On Tuesday the company announced the retirement of CEO John Burris. Burris had previously been on medical leave. Martin Roesch, Sourcefire's CTO, will continue to act as interim CEO until a replacement is found.

Interested in more on Sourcefire? See TheStreet Ratings' report card for this stock.

-- Written by Chris Ciaccia in New York

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