Toshiba Plans to Double Hard-Drive Output; Seagate Falls 10%

A factory story came out of Tokyo on Friday morning.

It described an investment of roughly $380 million. By the closing bell in New York, Seagate alone had shed more than 50 times that in market value.

What Toshiba Is Planning

According to the Japanese business daily Nikkei, Toshiba will invest about ¥60 billion in its hard-drive plant in the Philippines. The goal is to double production capacity within fiscal 2027, which ends in March 2028.

Its market share by capacity is just over 10% today. The medium-term target is 30%.

The new lines will build drives holding up to 40% more data per unit. Toshiba is pitching the move as a response to storage demand from AI data centers.

A Three-Company Market

Only three hard-drive makers are left. Seagate and Western Digital each hold more than 40% of the market by exabytes shipped, and Toshiba holds the rest.

AI spending transformed this market within a year. Data centers still store bulk data on hard drives, because the cost per terabyte is lower than on SSDs.

Seagate reported fiscal 2026 revenue of $12.2 billion, up 34%. Its gross margin reached 52.3% in the June quarter.

One assumption held that picture together: none of the three makers was adding new unit capacity. Seagate's management had said a new factory would take at least two years, and that it had no such plans.

Supply growth came only from technology that fits more data on each drive.

The Market Did Not Read This as a Capacity Story

It read it as a discipline story.

Toshiba's plan adds roughly 10% to industry exabyte supply over two years. Seagate alone targets about 25% annual exabyte growth from HAMR, its heat-assisted recording technology. In volume terms, the new supply is small.

But margins depend on price, not volume. In a three-player market, once one player starts adding capacity, the question of where prices go is open again.

That outsized effect was what carried the stock. Analysts expected Seagate's earnings per share to rise from $15.58 in fiscal 2026 to above $35 in fiscal 2027. That forecast assumed prices would not soften.

What Happened on Friday

The report broke during the Asian session. Both stocks sold off hard from the U.S. premarket onward. Seagate's intraday loss topped 14% before narrowing to 10% at the close.

The broader market rose the same day. A weak jobs report cut the odds of an October Fed rate hike, and money rotated back into growth stocks.

So the selling did not come from the market as a whole. The closing figures separate the two clearly.

The two stocks were the S&P 500's worst performers of the day, which points to a sector-specific sell-off. Seagate's last six months show the level this drop came from.

The Part That Does Not Fit

Several analysts called the sell-off overdone. Morgan Stanley kept Buy ratings on both stocks, arguing that the supply gap through 2028 is wider than anything Toshiba can add.

Citi analyst Asiya Merchant noted that Toshiba buys critical components such as heads and media from outside suppliers. That could limit how much real capacity reaches the market. Morgan Stanley also pointed out that Toshiba lacks HAMR technology.

There is one more detail. Toshiba went private in 2023, so its shares do not trade. The market cannot price the return on its investment, only the damage to its rivals.

What Is Left

Not a single new drive reached the market on Friday. Turning the plan into real supply will take years, and customers need additional time to qualify new drives.

What changed is not today's supply but the price assumption for the future. When Seagate and Western Digital report in late October, the first question will likely be about their own capacity plans. For the earlier margin debate: our Western Digital and SanDisk story. For how valuation hangs on assumptions like these: How Does Valuation Work?

This story is based on Investing.com and Yahoo Finance relays of Nikkei's Oct. 2 report, Seagate's July 28 fiscal 2026 earnings release, 24/7 Wall St.'s Oct. 2 closing data, and press accounts of notes from Morgan Stanley and Citi. Toshiba's plan comes from a newspaper report, not a company statement. Seagate's market-value loss is an approximation based on its $945.57 prior close and the 229 million diluted shares it reported. Market-share figures are as reported by those outlets.