Skip to content
    DiamondStream Partners logo

    DiamondStream Partners

    Seattle, Washington, United StatesFounded 2003

    DiamondStream Partners is a venture capital firm founded in 2003 and based in Seattle, Washington. The firm invests in middle-stage aerospace, aviation, and mobility transformation companies, primarily in the US and Europe, leveraging deep operational and investing expertise to help founders scale their businesses.

    43% of their portfolio is in Logistics & Supply Chain. Their most common stage is series-b (43% of deals). Average disclosed round size is $22.0M (across 4 rounds with reported amounts).

    Find people at DiamondStream Partners on Goldilocks AI

    Portfolio

    5

    Fund Size

    Top Stage

    Series B

    Last 12 Mo

    0

    Team

    BC

    Brian Charles Flynn, Jr.

    Managing Director and Co-founder

    WD

    William Dean Donovan

    Managing Director and Co-founder

    DJ

    David John Spurlock

    Managing Director

    TH

    Traci Ho Kim

    Vice President

    Portfolio Breakdown

    Stage Distribution

    Sector Distribution

    Investment Activity

    Portfolio

    7 investments
    CompanyRoundAmountDate
    Elroy Air logoElroy AirUnknownJan 2025
    Elroy Air logoElroy AirUnknownOct 2024
    Elroy Air logoElroy AirSeries A$40MAug 2021
    GPMS logoGPMSSeries AFeb 2021
    AMPAIRE logoAMPAIRESeries B$19M
    Ampaire logoAmpaireSeries B$19M
    SwissDrones logoSwissDronesSeries B$10M

    Top Co-Investors

    Marlinspike3 shared
    Alaska Star Ventures2 shared
    Techstars2 shared
    Gaingels2 shared
    Massive1 shared
    KBW Ventures1 shared
    Ingleside Investors1 shared

    Last updated: 8 September 2026