SK Hynix Rose on Korea's Record Chip Exports, Kioxia Fell 16%

On Friday the Philadelphia Semiconductor Index fell 7.2% in the US, and the Kospi dropped more than 3% the same day. In Seoul on Monday morning the selling carried on at first, with the index opening 1.62% lower.

By the close the picture had flipped. The Kospi rose 2.24% to 5,859.08, a turn driven by October export data released on Sunday.

Chips Are Now Half of Korea's Exports

According to Korea's trade ministry, October exports rose 93.7% from a year earlier to $115.3 billion. Imports grew 36% to $72.8 billion, leaving a trade surplus of $42.5 billion.

Semiconductor exports jumped 259.4% to $56.4 billion. Chip exports topped $50 billion for a second straight month and reached roughly half of the total.

Exports to the US rose 185.8% to $24.9 billion, which the ministry tied to chips, computers and electrical equipment for AI infrastructure. Exports to China climbed 133.6% to about $27 billion.

January-to-October exports reached $930 billion, passing $900 billion for the first time. The ministry says annual exports could hit $1 trillion in November.

Three Quarters of the Gain Came From One Line

Annual growth rates alone say little. To see which line carried the growth, you have to back out last year's amounts.

A 34% rise outside chips is still strong, but it includes a base effect. Last year the Chuseok holiday fell in October; this year it moved into September, adding working days to October.

According to secondary reports, adjusting for working days cuts the rise in average daily exports to 76%. The base effect inflates the headline, but it does not change chips' weight in the increase.

Two Different Memory Stories on the Same Morning

Memory stocks rallied in Seoul. SK Hynix rose 3.81% to 1,472,000 won (about $1,095), and Samsung Electronics gained 1.78% to 229,000 won (about $170).

Conversions use 1,343.8 won and 157.8 yen per dollar. Kioxia, meanwhile, fell 15.8% in Tokyo to 11,345 yen (about $72).

The market did not read these as one memory story. It read them as two separate price curves.

Kioxia sells only NAND, or flash memory. On Friday it said growth in NAND average selling prices would slow from 70% in April-June to single digits in October-December.

Korea's chip exports, by contrast, lean on DRAM and high-bandwidth memory (HBM). TradingKey tied the Kioxia sell-off to its guidance and to the company's lack of HBM exposure.

The Part That Doesn't Fit

Retail investors did not drive the rally. According to the Korea Times, individuals were net sellers of 1.41 trillion won (about $1.05 billion) on Monday, while institutions bought 1.36 trillion won.

Foreigners were light sellers at 43 billion won. JoongAng Daily puts institutional buying at 1.23 trillion won, so the two sources' flow data do not match.

The government stepped in the same day. President Lee Jae-myung told parliament his budget sets aside 21.3 trillion won (about $16 billion) for AI, chip and data-center projects, nearly double this year's amount.

After Friday's sell-off, Micron shares rose more than 2% in overnight trading on Sunday, according to secondary reports. The chart shows the past three months and does not prove direction; it only frames the scale of the sell-off.

What It Means for Investors

• On Friday the market priced in slower AI spending; Korea's data show memory demand accelerating in October, but not how long price gains will last.
• Micron sits on the same DRAM and HBM curve as Korea, while SanDisk and Western Digital sit on the NAND curve Kioxia described.
• The threshold to watch is chips' 49% share of Korean exports, and whether early-November data stay above a $50 billion monthly pace.
• The risk to the thesis is DRAM price growth slowing to single digits like NAND; then stocks would sell the growth rate even if exports stay high.

The Sector Rotation guide explains why separating price from volume matters in cyclical sectors. SanDisk's latest quarter is covered in detail in the earnings analysis.

Sources: Export data come from Korea's trade ministry release of November 1, 2026, as reported by Yonhap and JoongAng Daily. Kospi, share and flow data come from the Korea Times and JoongAng Daily, and Tokyo and Taiwan moves from AP and TradingKey. The budget remarks rely on a Reuters report. Last year's amounts and the 73% share were back-calculated from the published percentages. The working-day-adjusted 76% and Micron's overnight move rest only on secondary reports.