Check out the companies making headlines after the bell Monday:
Shares of technology giant Alphabet climbed after the bell Monday, ballooning its market capitalization to $570 billion to unofficially surpass Apple as the world's largest company. The technology giant posted quarterly earnings that beat analysts estimates by a wide margin, with earnings per share of $8.67 on revenue of $21.33 billion, versus the expected $8.10 earnings on $20.77 billion.
The Internet company's aggregate paid clicks, a key advertising metric, rose 31 percent from the previous year, beating consensus expectations of about 22 percent, according to StreetAccount. Fellow advertising platform LinkedIn also bounced after hours ahead of its earnings announcement this Thursday.
Global toy manufacturing company Mattel, which makes brands like Barbie, Hot Wheels and UNO, also popped after hours. Mattel posted higher-than-expected adjusted earnings of 67 cents per share on revenues of $2 billion, surpassing estimates of 61 cents per share, adjusted, on $1.91 billion in revenue. The toymaker made headlines last week after redesigning the iconic Barbie doll to reflect different body sizes and ethnic diversity.
Anadarko Petroleum shares edged higher in extended trading, despite reporting a quarterly loss. The company posted a quarterly loss of 57 cents per share on $2.05 billion in revenue — a softer landing than the $1.08 loss per share on $2.10 billion in revenue predicted by analysts. Shares of the Texas-based oil and gas exploration company are down more than 53 percent over the past year as historically low oil prices have choked the energy sector.
An earnings beat also sent shares of Aflac higher after the bell. The supplemental insurance company posted adjusted earnings per share of $1.56 on $5.32 billion in revenue, topping estimates of $1.47 per share, adjusted, on $5.22 billion.
Shares of American International Group dipped in extended trade after it released more information on its ongoing "strategic update." The insurance company was downgraded to "market perform" from "outperform" at BMO Capital Markets, saying AIG will have a tough time delivering on the financial targets announced last week in AIG's new strategic plan.
shares sank after hours, giving up some of the day's gains after it announced its completed merger with chipmaker and Apple iPhone supplier Avago Technologies. Apple reported last week it sold 74.8 million iPhones in the quarter, missing expectations of about 75.46 million, according to StreetAccount.
— CNBC's Jacob Pramuk, Everett Rosenfeld and Peter Schacknow contributed to this report.