“Except for our two team leads, my entire team [of 30 people] just applied to SK Hynix,” Lee says, referring to a job posting the company published in July. Lee, who has worked at Samsung for three years, even applied for an entry-level position at its rival. A coworker, who has worked at Samsung for eight years, applied for the same one. They both got rejected. But they’re hopeful that they’ll get a callback for a posting seeking a more experienced engineer.

All employees at Samsung and SK Hynix that MIT Technology Review spoke with asked to be identified by just their last name or a pseudonym because they feared retaliation from their employer. Samsung declined to comment, and SK Hynix did not respond to requests for comment.

After prolonged negotiations with its labor union, Samsung struck a deal in May to pay out 10.5% of the semiconductor division’s operating profits to employees as bonuses annually for 10 years, mostly in company stock that vests over three years. The move came after SK Hynix agreed last year to pay out 10% of operating profits to employees, which translates to $476,000 per employee this year—mostly in cash.  

But at Samsung, each division’s bonus is tied to its own bottom line. Chip workers in its memory division, which is also reaping a windfall from making HBM chips, are getting paid a bonus of roughly $400,000 per employee this year. But those who, like Lee, work in Samsung’s foundry division, which manufactures logic chips that companies like Tesla and Google design and has been operating at a loss, are getting a bonus of roughly $135,000. 

Employees told MIT Technology Review that Samsung said it can’t give as many bonuses to divisions that aren’t performing well. Lee, after watching the labor union wrestle with the company for months, says he has felt disappointed by what he ended up with: “Even if Samsung does well in the future, I don’t think any of it will trickle down to me.” 

The workers’ lagging bonuses are making SK Hynix suddenly look appealing. According to a survey by the Samsung labor union in June, 81.5% of employees in the company’s foundry division, and nearly half of employees in the semiconductor division as a whole, said they wanted to go to another company in the next two years. In April, Samsung labor union chief Choi Seung-ho said more than 200 members of the union had left for SK Hynix over the past four months. On Blind, an anonymous workplace forum, a chorus of disgruntled engineers at Samsung confess that they want to defect to SK Hynix for the bigger bonuses. 

For decades, SK Hynix lived in Samsung’s shadow. It was the smaller, scrappier memory maker that elite engineering students at universities looked past when applying for jobs. But in 2019, Samsung downsized its HBM team, betting the market would stay niche, while SK Hynix doubled down on the technology. Then the AI boom supercharged the demand for HBMs, which feed AI chips the enormous amounts of data they need at ultra-high speed, driving prices to unprecedented levels. SK Hynix now leads the global market for HBMs, while Samsung is playing catch-up. Both companies topped $1 trillion in market value in May, and SK Hynix briefly dethroned Samsung as South Korea’s most valuable company in June.