The storage maker's June-quarter results come in ahead of Wall Street's expectations, and the stock rallies after hours

Seagate's stock was rising after its fiscal fourth-quarter earnings report on Tuesday afternoon.

Seagate Technology's stock was staging a comeback in after-hours trading Tuesday as investors got a fresh sign of ongoing demand for storage products.

The data-storage maker reported fiscal fourth-quarter revenue of $3.6 billion, up 48% from a year ago, and ahead of the FactSet consensus for $3.5 billion. Seagate's adjusted earnings of $5.71 per share for the June quarter also topped expectations for $5.10.

"Our performance is being driven by robust cloud data-center demand and disciplined execution, and we see the momentum continuing in 2027," Seagate CEO Dave Mosley said in a statement.

Mosley said the company expects "durable long-term demand for mass capacity storage" as artificial-intelligence drives the creation of more data.

For the full fiscal year 2026, Seagate said its revenue grew 34% to $12.2 billion. Analysts tracked by FactSet had been looking for annual revenue of $12 billion. The company also saw a record $3.1 billion in free cash flow in the fiscal year, it said.

Seagate's stock $(STX)$ was up 5.2% in after-hours action after closing down 8.5% on Tuesday. Shares of fellow storage maker Western Digital $(WDC)$ also got a lift, rising 2.5% after having shed 6.9% in the regular session.

Sandisk's stock $(SNDK)$ was up 2.8% in extended trading Tuesday after ending the trading day down 14.3%, while Micron Technology's $(MU)$ was up 1.4% after having closed 8.8% lower. SK Hynix's American depositary receipts (SKHY) were up 4% in after-hours trading after falling 8.9% on Tuesday.

Shares of the memory and storage companies extended declines Tuesday following chip-technology developments in China that have spooked investors in Asia and the U.S.

Chinese memory-chip maker ChangXin Memory Technologies (CN:688825) saw its stock pop 466% on its debut in Shanghai on Monday. That was followed by a Monday report from The Information that a Chinese state-backed semiconductor-equipment company has started mass producing deep-ultraviolet lithography machines for domestic chip makers including Semiconductor Manufacturing International Corp. (HK:981) and Hua Hong (CN:688347).

Shares of South Korean memory-chip makers SK Hynix (KR:000660) and Samsung Electronics (KR:005930) plunged 14% and 13%, respectively, on Tuesday.

Sylvia Jablonski, chief investment officer at Defiance ETFs, said the market was "reacting to the strategic implications rather than the near-term commercial impact."

While China's reported progress on DUV systems is another signal that U.S. export controls are accelerating the country's efforts for self-sufficiency, Jablonski said that's something to watch over the long term.

"Investors should distinguish between a long-term increase in Chinese technological competitiveness and an immediate threat to the earnings power of leading U.S. semiconductor companies," Jablonski said in emailed comments to MarketWatch.

-Britney Nguyen