SK Hynix is starting to remind me of Ericsson in Sweden’s 1999–2000 tech bubble

I was looking at SK Hynix’s growing influence on the Korean market and it reminded me of something that happened in Sweden during the dot-com bubble. Ericsson became absolutely enormous relative to the Swedish stock market. At the peak, it was more than one-third of the total market cap of the Stockholm exchange. The numbers around the top are kind of crazy. From October 1999 to March 2000, the Swedish market added around SEK 2.3 trillion in market value. Ericsson alone accounted for roughly 60% of that increase. When the market turned, the same thing happened in reverse. Around 60% of the decline came from Ericsson. And the Swedish market didn’t really get back above that old peak for almost 15 years. I’m starting to wonder if SK Hynix is creating a similar situation in Korea. Obviously the two companies are very different, and I’m not saying Korea is literally Sweden in 2000. SK Hynix could keep growing for years. What interests me is the concentration itself. When one company becomes such a big part of a country’s stock market, the index starts behaving less like a diversified bet on the country and more like a bet on one company and one technology cycle. Ericsson is also an interesting example because it wasn’t some useless dot-com company. It was a great company sitting right in the middle of a technology revolution that actually happened. The internet happened. Mobile communications exploded. Ericsson survived. The stock still became a huge problem for the Swedish market. That’s the part of the comparison I find interesting.