First In | Activity | F4

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Team Portfolio Raise Champions Essays

F4/First In/Activity

First In Activity

Every public signal F4 has attached to this firm, with sources and cross-entity links.

Types

Time range

Milestone

Castelion awarded $90M firm-fixed-price order from the U.S. Navy to advance Blackbeard hypersonic strike weapon to Early Operational Capability, funding 50 EOC weapons and transition to a Navy Program of Record.

Castelion

Castelion First In

castelion.comAUG 25, 2026

wsj.com

AUG 25, 2026

Investment

First In co-led Smack Technologies' $61M Series B round alongside Costanoa Ventures to build AI hardware for intelligent autonomy at the tactical edge. Smack is the first frontier AI lab for national security, founded by MARSOC veterans.

Smack Technologies

Smack Technologies First In

smacktechnologies.comAUG 18, 2026

AUG 18, 2026

Essay

Renny McPherson published a thesis essay arguing that defense tech is undergoing a structural migration similar to the 2005-2011 cybersecurity boom, and that today's winners (Castelion, Saronic) will become the next generation of prime contractors.

First In

First InFirst In

wearefirstin.comAUG 14, 2026

AUG 14, 2026

Team Change

Rebecca Gevalt joined First In as General Partner, helping lead the firm's venture growth-stage strategy and extending the firm's ability to partner with founders from early innovation through scaled growth.

First In

First InFirst In

wearefirstin.comJUL 30, 2026

JUL 30, 2026

5 investments· MAR 2026 – APR 2026Show all

Investment

Co-led Rilian's $17.5M seed and seed-extension financing for agentic AI cyber and defense operations.

Rilian Technologies

Rilian Technologies First In

businesswire.comAPR 23, 2026

APR 23, 2026

Investment

Portfolio company Cloneable emerged from stealth with $4.6M seed funding for AI-driven platform that shadows human experts and automates their workflows on edge devices.

Cloneable

Cloneable First In

wearefirstin.comAPR 23, 2026

APR 23, 2026

Investment

Led SCATR's Series A investment for their data-in-transit security platform using post-quantum encryption and dynamic routing.

Scatr

Scatr First In

wearefirstin.comAPR 22, 2026

scatrcorp.ai

wearefirstin.com

APR 22, 2026

Investment

Invested in Hybron's advanced composite manufacturing platform for defense and aerospace, enabling 10-100x faster production of critical components.

Hybron

Hybron First In

wearefirstin.comAPR 17, 2026

lowenstein.com

wearefirstin.com

APR 17, 2026

Investment

Led Vanguard Defense's $5M seed round for defense AI data observability infrastructure.

Vanguard Defense

Vanguard Defense First In

businesswire.comMAR 25, 2026

wearefirstin.com

MAR 25, 2026

New Fund

Closed First In Fund 3 SBIC Critical Technologies, LP with $148M of investable capital for early-stage security technology businesses.

First In Fund 3 SBIC Critical Technologies, LP

First In

businesswire.comMAR 5, 2026

wearefirstin.com

MAR 5, 2026

New Fund

Closed Fund III with $148M in investable capital as a Small Business Investment Company Critical Technologies fund.

Fund III (SBIC Critical Technologies)

First In

wearefirstin.comMAR 5, 2026

MAR 5, 2026

Investment

Participated in Smack Technologies' $32M funding through Series A for national-security AI decision systems.

Smack Technologies

Smack Technologies First In

finance.yahoo.comMAR 2, 2026

MAR 2, 2026