Stocks making the biggest moves after hours: Activision Blizzard, TripAdvisor, Akamai and more
Check out the companies making headlines after the bell:

Shares of Activision Blizzard were volatile in extending trading Tuesday following a mixed fourth-quarter earnings report and weak outlooks for both the first quarter and full year. The stock initially fell 3 percent after the company reported earnings of $1.29 per share on revenues of $2.84 billion. Analysts expected earnings of $1.28 a share on revenues of $3.04 billion, according to Refinitiv consensus estimates.

Activision also issued weak first-quarter guidance, saying it expects earnings of 20 cents a share on $1.18 billion in revenue, compared to the estimated earnings per share of 46 cents on $1.45 billion in revenue. For 2019, Activision estimates earnings of $2.10 per share on revenues of $6.3 billion, also below the estimated earnings of $2.54 per share on revenue of $7.25 billion.

The company also announced on the conference call that it is cutting its workforce by 8 percent. The stock was last seen about 2 percent higher in after-hours trade.

TripAdvisor shares dropped as much as 6 percent following mixed earnings. The travel and restaurant website company reported $346 million in revenue, beating estimates of $343 million. Earnings per share were 27 cents, compared to the 29 cents expected by Wall Street. Revenue was driven by its non-hotel segment, which saw year-over-year growth of 38 percent. The stock is up more than 60 percent over the last year.

Akamai shares were volatile in extending trading after posting better-than-expected fourth-quarter earnings. The stock initially rose about 3 percent after the Massachusetts-based technology company beat on the top and bottom lines. It reported $713 million in revenue, compared to estimates of $704 million. Earnings per share were $1.07, higher than the expected $1 expected by analysts. The company also announced CFO Jim Benson will retire in March. He will be succeeded by Ed McGowan, the senior vice president of finance. The stock was last seen about 2 percent lower.

Shares of Groupon fell more than 14 percent after market close on Tuesday after posting mixed earnings. Earnings per share were 10 cents, missing estimates by 3 cents. Revenue was $800 million, compared to the $789 million forecast by analysts. North American active customers fell 2.5 percent to 30.6 million.

Twilio shares fell more than 4 percent after hours Tuesday despite better-than-expected earnings. The cloud communications company reported fourth-quarter earning of 4 cents per share on revenues of $204 million. Analysts had expected earnings per share of 4 cents on revenues of $185 million.