Of the 15,045 union members who participated in the ballot, 50.08% voted against the proposed agreement, while the remaining workers backed the deal, the source said.
The source, who spoke on condition of anonymity because they were not authorised to speak to the media, said the extremely close outcome reflected divisions among workers over the proposed changes to the company’s bonus structure.
SK Hynix was not immediately available for comment when contacted by Reuters.
The agreement, which was reached between the company and its union last week, included a 6.3% wage increase. It also proposed changes to the company’s profit-sharing bonus scheme, with 40% of bonuses to be paid in cash and the remaining 60% distributed in SK Hynix shares.
Workers Raise Concerns Over Share-Based Bonuses
The disagreement comes as SK Hynix continues to benefit from strong demand for high-bandwidth memory (HBM) chips, which are increasingly used in artificial intelligence systems. The company is the world's second-largest memory chipmaker and has reported strong profits amid the rapid expansion of AI-related demand.
Last year, SK Hynix and its workers agreed to a 10-year profit-sharing arrangement under which 10% of the company’s annual operating profit would be set aside for bonus payments.
Under the existing system, 80% of the bonus is paid in cash in the year it is awarded, while the remaining 20% is deferred over two years.
However, some workers opposed this year’s proposal to shift a larger portion of the bonus into company shares. Their concerns were reportedly linked to the volatility of SK Hynix’s stock and the uncertainty surrounding the eventual value of the share-based payments.
SK Hynix shares reached a record high in June as investors continued to bet on the company’s prospects in the AI boom. The stock has since come under pressure amid concerns over heavy spending and whether the investment will generate sufficient returns.
Samsung Deal Adds Pressure to Chip Industry
The dispute at SK Hynix comes after Samsung Electronics and its unionised workers reached an agreement in May on a performance-pay system, averting a major strike that had raised concerns about possible disruptions to chip supplies.
Under Samsung’s agreement, 10.5% of its annual semiconductor operating profit would be allocated to special bonuses for chip workers. The bonuses would be paid in company stock, although workers would face restrictions on the immediate sale of most of the shares.
The developments highlight the growing importance of compensation negotiations in South Korea’s semiconductor industry, where workers are seeking to share more directly in the gains generated by booming demand for AI chips.
By 0036 GMT on Tuesday, SK Hynix shares were down 4.9%, compared with a 2.2% decline in the benchmark KOSPI index.