Most Active AI Infrastructure Investors in Seattle 2026

10 firms writing AI Infrastructure checks in Seattle, led by Venrock, Felicis, Index Ventures — ranked by verified deal count with the companies behind each.

AI Infrastructure in Seattle accounts for 3 tracked companies with verified cap-table data, 3 of which disclose round sizes totalling $331M. The median disclosed raise is $120M, and the largest is Gradial at $120M, ahead of Phaidra ($120M) and Supio ($91M).

The names that recur most often on these ai infrastructure cap tables are Insight Partners (1 company), VMG Partners (1 company), Madrona (1 company), Pruven Capital (1 company), General Advance (1 company), Outsiders Fund (1 company). By latest disclosed round, the market skews Series B (2), Series C (1).

Best funded AI Infrastructure in Seattle companies

  1. Gradial — $120M (latest: Series C)
  2. Phaidra — $120M (latest: Series B)
  3. Supio — $91M (latest: Series B)

Sector × city funding reports (20)

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