Check out the companies making headlines after the bell:

IBM shares fell nearly 4 percent after the bell. The computer technology company announced fourth quarter financial results that surpassed Wall Street expectations. IBM reported $22.5 billion in revenue, breaking a 23 quarter streak of declining year-over-year revenue decline.

The company also projected revenue growth in the upcoming quarter, despite a one-time, $5.5 billion charge from tax reform.

American Express stock fell nearly 2 percent in extended trading. The credit card company beat analyst expectations on fourth quarter earnings and revenue, but announced a suspension of dividend buybacks, citing upfront charges from tax reform.

"We plan to suspend our share buyback program for the first half of 2018 in order to rebuild our capital," American Express CEO Kenneth Chenault said.

Shares of Mellanox Technologies jumped nearly 7 percent in the extended session. For the fourth quarter of 2017, the computer supplies manufacturer reported record high revenue that saw 7 percent growth year-over-year. Mellanox also announced strong guidance for fiscal 2018.