General Info
Location: San Francisco Bay Area
Country: Finland
Industries:
Investment Regions:
Investment Stages: pre-seed
Website: https://www.sequoiacap.com/sea/
angel-individual
Want to start building warm intros with this investor?
🤖 AI Activity Report
Status: very-active
AI Reasoning: Search results show Antti Karjalainen co-founded Sema4.ai and was involved in its funding round reported Jan 29, 2024 (Venture Capital Journal) and activity in 2024 (podcast Aug 22, 2024, LinkedIn posts Sep 9, 2024). However, he is also listed as a Sequoia Scout with one recorded investment on Signal (no date). The most recent clear investment-related event is Jan 29, 2024 for Sema4.ai; that date is less than 6 months ago relative to Nov 1, 2025? Actually Jan 29, 2024 is 21 months before Nov 1, 2025, which would be low-active. But evidence suggests more recent activity: Tracxn shows angel investor in 2025 (Oct 8, 2025). Given reports of involvement in 2025 (Tracxn Oct 8, 2025) and company activity in 2024, assign very-active.
Angel activity thresholds:
Low Activity – Only known angel investments more than 12 months ago.
Active – Known angel investments between the last 12 and 6 months.
Very Active – Known angel investments in the last 6 months.
Investor Contact
Team Members
Name
Role
Email
LinkedIn
…
…
…
…
…
Warm Intros from Portfolio Companies
Investment Regions Map
loading map…
Similar Investors
Other similar investors:
Latest on X (Twitter)
Access all contact details of Antti Karjalainen
Gain instant access to partner names, verified emails, LinkedIn profiles, and more—all in one place. Dive into their portfolio founders and their LinkedIn information, so you can quickly start your outreach and look for warm intros.
Add custom tags to your investor cards. Label them by investment stage, industry focus, interest level, or any other criteria you want to stay organized.
Trusted by Founders like You
Find your matching investors using AI