Check out the companies making headlines after the bell Monday:
Shares of biopharmaceutical developer Juno Therapeutics shot up as much as 67 percent after it announced a 10-year partnership with Celgene to advance "potentially groundbreaking immunotherapies" for cancer.
Celgene will make an initial payment of about $1 billion, which includes the purchase of 9.1 million shares of Juno stock. Celgene shares fell as much as 1 percent after the announcement.
Apollo Education Group's shares fell about 6 percent the academic service provider reported third-quarter adjusted earnings of 53 cents, down from 78 cents a share a year ago, while revenue declined 14 percent to $681.5 million. The company runs the for-profit University of Phoenix program.
AOL, now owned by Verizon, said it will manage and sell Microsoft's display, mobile and video ad inventory. The media firm's search engine will be powered by Microsoft's Bing solution in 2016. Microsoft shares inched lower in extended trading.