Shares of IBM Corp. (IBM - Get Report) dropped more than 4% after-hours after the company beat earnings estimates but missed on revenues for the third quarter. 

The tech giant, which has struggled in recent years, reported earnings of $3.42 per share on revenue of $18.8 billion, versus analyst expectations of $3.40 per share and revenue of $19.1 billion.

IBM's Cognitive Solutions segment, which includes solutions software and transaction processing software, reported quarterly revenues of $4.1 billion, down 6% year over year, while its Technology Services & Cloud Platforms group had revenues of $8.3 billion, down 2%.

In the second quarter, IBM was able to slightly beat analysts' estimates for top- and bottom-line estimates. The performance was mainly fueled by the company's Systems segment, which covers sales of hardware and operating system software. In the third quarter, the Systems segment reported revenues of $1.7 billion, up 1% (up 2% when adjusting for currency).

IBM closed Tuesday's session up nearly 3% before giving up those gains and more after-hours.