Kai Chen, a prominent Canadian AI researcher at OpenAI known for her key contributions to the GPT-4.5 model, has had her application for a U.S. green card denied, despite residing in the United States for the last 12 years. The surprising denial was first disclosed by her colleague, Noam Brown, a leading research scientist at OpenAI. According to Brown, Chen received the unfortunate news last Friday and will soon be forced to relocate out of the country.
In a public statement, Brown expressed frustration and concern over the decision, describing Chen as one of the most capable AI researchers in his experience. “It’s deeply troubling when America rejects highly talented individuals who have spent years contributing significantly here,” Brown remarked, adding that such decisions undermine U.S. leadership in artificial intelligence.
Another OpenAI employee, Dylan Hunn, affirmed Chen’s invaluable role in the development and success of GPT-4.5, calling her contributions “crucial” to the highly regarded AI model.
Chen’s denial is part of a wider pattern emerging under the Trump administration, which has increasingly posed barriers to foreign nationals seeking permanent residency. Recently, more than 1,700 international students and researchers in the U.S. have had their visas scrutinized or revoked amid a broader government crackdown. While authorities have justified some revocations by alleging political affiliations or controversial activities, other individuals have lost their status due to minor offenses such as traffic violations and petty legal infractions.
The administration’s stringent immigration policies have also reportedly halted processing for substantial numbers of permanent residency applications filed by individuals previously granted refugee or asylum status. Additionally, green card holders viewed as possible national security concerns have faced detention and threats of deportation.
This climate is particularly troubling for the AI research community, heavily reliant upon talent drawn from around the world. According to one contract worker from OpenAI, Shaun Ralston, the company alone filed over 80 H-1B visas last year and has sponsored more than a hundred since 2022. H-1B visas are often used by technology businesses to hire skilled international staff in positions requiring specialized expertise.
Immigrant scientists have long played a central role in the rise of the U.S. as a global leader in artificial intelligence. A Georgetown University study found immigrant founders behind 66% of Forbes’ top AI startups, and another recent analysis revealed that international students constitute roughly 70% of graduate students in AI and related fields.
High-profile examples include AI pioneers such as Ashish Vaswani, an immigrant and key co-inventor of the transformer model—the architecture foundational to systems like ChatGPT—and OpenAI co-founder Wojciech Zaremba, who earned his Ph.D. in AI at New York University as an international student.
Recently, increasing restrictive policies, shrinking research grants, and rising antagonism toward certain sciences have caused many researchers to reconsider their future within the United States. In a Nature poll of over 1,600 scientists, 75% responded that they were considering pursuing careers outside the U.S.
Chen’s case highlights ongoing debates around the challenges that current immigration policy poses to America’s competitive edge in technology and innovation. Sam Altman, OpenAI’s CEO, previously advocated for immigration reform, stressing the importance of retaining global talent to maintain America’s position at the forefront of technological advancement. Chen intends to continue her work remotely, temporarily based out of Vancouver, as she awaits resolution to her immigration status.
