After-hours buzz: AA, LULU, UA & more

A trader on the floor of the New York Stock Exchange.
Lucas Jackson | Reuters
A trader on the floor of the New York Stock Exchange.

Check out the companies making headlines after the bell Monday:

Alcoa shares jumped in after-hours trading Monday after the company reported mixed quarterly results. The metals and mining company kicked off earnings season with fourth-quarter earnings of 4 cents per share, topping analyst expectations. But it fell just short of predictions on revenue, coming in at $5.25 billion. Later this year, Alcoa plans to separate into two publicly traded companies, one housing its legacy aluminum and smelting operations and the other its higher-growth materials segment.

Apollo Education Group's stock spiked after the bell on chatter that it was considering selling itself after years of declining enrollments, Reuters reported. One potential buyer? Private equity firm Apollo Global Management, which could shell out as much as $1 billion for the for-profit education company behind University of Phoenix, The Wall Street Journal reported.

Athleisure brand Lululemon Athletica also saw a boost in extended trading after upping its revenue forecast for the fourth quarter of fiscal 2015. The brand now expects net revenue in the range of $690 million to $695 million, revised up from $670 million to $685 million, and earnings per share of between 78 cents and 80 cents, up from 75 cents to 78 cents. Lululemon attributed the anticipated 15 percent year-on-year sales increase to a successful holiday shopping season, according to the company statement.

Under Armour also saw shares rise modestly in extended-hours trading, rebounding after closing down almost 7 percent during the regular session. Morgan Stanley downgraded the athletics apparel name to "sell" and lowered its price target to $62 from $103, citing falling market share and declining average selling price in footwear. But another analyst at Bank of America Merrill Lynch said those concerns were "overblown" and maintained a "buy" rating on the stock.

Shares of off-price retailer Burlington Stores popped when the company reaffirmed its earnings and revenue would likely come in on the low end of guidance, with flat same-store sales. Unseasonably warm weather was a headwind for the company's flagship item, coats. But excluding cold weather categories, same-store sales are expected to have increased about 4 percent in the quarter, the company said in a release.

— CNBC's Jacob Pramuk and Pippa Stevens contributed to this report.