SKHY vs 000660: How the Two Ways to Own SK hynix Differ

There are two ways to own SK hynix from outside Korea. SKHY is an American depositary share (ADS) listed on Nasdaq, priced in US dollars and traded in New York hours. 000660 is the common share itself, listed on the Korea Exchange (KRX) in Seoul and priced in won. Ten SKHY ADSs represent one Korean share. What differs is the currency, the trading hours, the fees, how dividends and votes reach you, and the price: the two can drift apart.

Won amounts are converted at the won-dollar rate at the 15:30 Korea time close on the day named (Bank of Korea, ECOS): 1,338.3 won per dollar on October 14 2026 unless stated otherwise.

What is SKHY, and how does it relate to 000660?

SK hynix’s prospectus, filed with the US Securities and Exchange Commission (SEC), names Citibank, N.A. as the depositary and the Korea Securities Depository as its custodian. The custodian holds the Korean shares; Citibank issues the ADSs against them. The ADSs are registered on Form F-6 (filed July 1 2026) and listed on Nasdaq through Form 8-A.

The offering was priced on July 9, 2026: 177.9 million ADSs at US$149.00 each, about US$26.5 billion in total. They represent 17.79 million new common shares, about 2.4% of the 730,492,365 shares SK hynix reported as issued in August. The ADSs began trading on Nasdaq on July 10, 2026 under the temporary symbol SKHYV, and switched to SKHY on July 13, according to a notice from Singapore broker Phillip Securities and IPOScoop’s report on the first day.

How does the 10-to-1 ratio work?

The Form F-6 and the prospectus say each ADS represents one-tenth of one common share. To compare prices, convert the Korean price to dollars and divide by 10:

• SK hynix closed at 1,419,000 won on October 14, in the KRX regular-session closing auction. That is about US$1,060.30 per share.
• Divided by 10, it equals US$106.03 per ADS.

When do SKHY and the Korean shares trade, in Singapore and New York time?

Korea and Singapore do not change their clocks. The US does: daylight saving time ends on November 1, 2026, so New York moves one hour further from Asia.

Regular session	Korea	Singapore	New York
KRX (000660)	09:00–15:30	08:00–14:30	20:00–02:30 (19:00–01:30 from Nov 2)
Nasdaq (SKHY), to Oct 31	22:30–05:00	21:30–04:00	09:30–16:00
Nasdaq (SKHY), from Nov 2	23:30–06:00	22:30–05:00	09:30–16:00

The regular sessions never overlap. From Singapore, Seoul trades by day and SKHY by night, and Seoul opens four hours after SKHY closes (three from November). Each market reacts to news that broke while the other was shut.

There is a partial overlap outside regular hours. Since September 14, 2026 the Korea Exchange has also run a 16:00 to 20:00 after-hours session, according to The Korea Times. Nextrade, Korea’s alternative trading venue, also trades until 20:00 Korea time (19:00 in Singapore, 07:00 in New York until November), and US pre-market trading starts at 04:00 New York time.

What does each route cost?

SKHY. You pay your broker’s US share commission. The deposit agreement also lets Citibank charge, among other fees:

• up to US$5.00 per 100 ADSs (US$0.05 per ADS) on each cash dividend;
• up to US$0.05 per ADS as an “ADS services” fee on record dates the depositary sets;
• up to US$0.05 per ADS to create or cancel ADSs;
• the costs and spreads of converting won dividends into dollars.

Against an ADS worth about US$106, US$0.05 is roughly 0.05%.

000660. You need a broker with access to the KRX, and not every overseas platform offers it (see our guide to owning Korean shares from abroad). Since December 14, 2023 foreign individuals can open accounts with a passport number instead of registering first, according to the Financial Services Commission. You convert dollars or Singapore dollars into won at a spread your broker sets. And Korea charges a securities transaction tax of 0.20% of the sale price on KOSPI shares sold on the KRX. On one share at the October 14 close, that is 2,838 won (about US$2.12). The prospectus says the tax does not apply to trading on Nasdaq. Size differs too: one Korean share cost about US$1,060 on October 14; one ADS, a tenth of that.

Do SKHY holders get the dividend and a vote?

Yes, both, but through Citibank.

Dividends. SK hynix pays quarterly. For the second quarter of 2026 it declared 375 won per share, record date August 31 (Form 6-K, August 7). That is 37.5 won per ADS, about US$0.027 at the August 31 rate of 1,368.6 won per dollar. Citibank pays it in dollars after fees and taxes. Korea withholds tax on dividends to non-residents at 22% or a lower treaty rate, whether you hold shares or ADSs, according to the prospectus.

Votes. Each common share has one vote. An ADS holder can instruct Citibank to vote the shares behind their ADSs. If no instruction arrives, those shares are not voted. The prospectus warns that voting materials may not reach ADS holders in time.

Switching. ADS holders can cancel ADSs for Korean shares, for a fee. The reverse is not guaranteed: Citibank needs SK hynix’s consent to accept shares beyond a set limit, and a holder who withdraws shares may not be able to deposit them again, the prospectus says.

Why can SKHY trade above or below the Korean price?

The gap is easy to compute:

1. Take the KRX price of one share in won.
2. Divide by the USD/KRW rate to get dollars per share.
3. Divide by 10 to get the “Korean-equivalent” price of one ADS.
4. Divide SKHY’s price by that figure and subtract 1. A positive result is a premium; a negative one is a discount.

Worked example: the offer price. The prospectus gives SK hynix’s last price in Seoul on July 9 as 2,186,000 won. At ECOS’s 15:30 rate that day, 1,506.1 won per dollar, that is US$145.14 per ADS, so the US$149.00 offer price was 2.7% above the Seoul price. The prospectus itself uses 1,538.05 won, the Federal Reserve Bank of New York noon buying rate for July 2. On that rate the Seoul price is US$142.13 per ADS and the premium 4.8%. The exchange rate chosen moves the answer by two percentage points.

The latest close. On October 14 the Seoul close equals US$106.03 per ADS. The timing needs care. Seoul closes at 02:30 New York time; SKHY closes 13.5 hours later. A gap measured from the two closes mixes any real premium with whatever happened in between.

Gaps can persist because the sessions do not overlap, creating new ADSs can need the company’s consent, the investors differ and selling in Seoul carries the 0.20% tax. A gap shows how two markets priced the same claim at different moments. It does not show which price is right, or where either goes next.

How has SK hynix moved lately, in won and in dollars?

On October 13 SK hynix fell 10.09% in Seoul as the KOSPI fell 5.46%; on October 14 it fell another 1.66%. Over the five sessions from October 6 to 14 it fell 19.97%. Foreign investors held 49.12% of its shares on October 13, as our guide to foreign investor flows shows.

The currency changes the picture for dollar investors. From the July 14 close, the day the ADS offering settled, to the October 14 close, the Korean shares fell 25.82% in won. Over the same days the won strengthened from 1,493.0 to 1,338.3 per dollar, so a dollar bought 10.4% fewer won. In dollars, the Korean shares fell about 17.2%. SKHY’s own move over those dates also depends on how its premium or discount changed.

The market map shows SK hynix against the rest of the KOSPI 200 for each of these periods. For the business, see our HBM comparison of Samsung Electronics and SK hynix; for Samsung shares, see owning Samsung stock outside Korea.