Siuchoon Koay

Research Analyst

Siuchoon Koay is a research analyst on the global equity team at William Blair Investment Management. In this role, he covers large-cap global semiconductors. Before joining William Blair in 2025, Siuchoon was a senior analyst at Newton Investment Management in London, where he covered semiconductors. Before that, he was at Atherton Asset Management in Hong Kong, where he was a senior analyst in global technology. Siuchoon started his research career at Sanford C. Bernstein in Hong Kong, where he covered Asian hardware. Siuchoon received a B.S. in electrical engineering and computer science, and economics from Massachusetts Institute of Technology.

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Siuchoon Koay

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