Check out which companies are making headlines after the bell Wednesday:
Pershing Square Capital Management's William Ackman, told investors in a letter that it sold its Citigroup shares to help build a stakein Procter & Gamble . Ackman told CNBC his fund owns about $1.8 billion dollars worth of stock in P&G.(Click here for after-hours quotes.)
Microsoft - The software giant announced its new Windows 8 will be released on October 26. Shares edged higher in extended-hours trading. (Click here for extended-hours quote.)
IBM - The tech giant posted earnings of $3.51 a share, topping expectations for $3.42 a share. But the company posted revenue of $25.8 billion, missing Wall Street's expectations for $26.28 billion.Still, the company also raised its full-year earnings outlook, sending shares higher in after-hours trading. (Click here for extended-hours quote.)
American Express - Thecredit-card provider posted earnings of $1.15 a share, beating expectations for $1.09 a share. But the firm reported sales of $7.97 billion, below estimates for $8.1 billion. Shares edged lower in extended-hours trading. (Click here for extended-hours quote.)
Qualcomm - The telecommunications equipment company posted earnings of 85 cents a share on revenue of $4.63 billion, missing expectations for a profit of 86 cents a share on sales of $4.68 billion. Adding to woes, the company handed in a disappointing current quarter and full-year outlook, sending shares sharply lower in extended-hours trading. (Click here for extended-hours quote.)
Ebay - The online auction company posted earnings of 56 cents a share on revenue of $3.4 billion, edging past estimates for 55 cents a share on revenue of $3.36 billion.But the firm provided weaker-than-expected current quarter and full-year guidance. Shares hovered around the flatline in after-hours trading. (Click here for extended-hours quote.)
Yum Brands - The parent company of Pizza Hut and KFC posted earnings of 67 cents a share, missing expectations for 70 cents a share. But the company reported sales of $3.17 billion, beating expectations for $3.11 billion. (Click here for extended-hours quote.)
F5 Networks - The networking appliances company posted earnings of $1.14 a share, in line with expectations. Revenue came in at $362 million, easily topping expectations for $353 million.However, the firm handed in disappointing current quarter earnings revenue outlook, pushing shares lower in extended-hours trading. (Click here for extended-hours quote.)
News Corp - Citi upgraded the media conglomerate to "buy" from "neutral" and raised its price target to $26 from $22. Shares edged higher in after-hours trading. (Click here for extended-hours quote.)
Stryker - The medical equipment maker posted earnings of 98 cents a share on revenue of $2.1 billion, falling slightly short of expectations for a profit of 99 cents a share on sales of $2.13 billion. Shares slumped in extended-hours trading. (Click here for extended-hours quote.)
Xilinx - The tech company reported earnings of 47 cents a share on revenue of $583 million, topping expectations for 45 cents a share on sales of $575 million. But shares declined in extended-hours trading after the company said it expects current quarter sales to drop four to eight percent sequentially. (Click here for extended-hours quote.)
—By CNBC’s JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)
Questions? Comments? Email us at marketinsider@cnbc.com
