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Mare Liberum

www.mareliberum.com · Miami, FL

“The future of global stability is decided at sea. We invest at the intersection of critical technologies and the maritime domain — autonomous systems, electronic warfare, maritime domain awareness, and sovereign AI infrastructure — to ensure American and allied maritime dominance.”

01Investment Thesis

The future of global stability is decided at sea. We invest at the intersection of critical technologies and the maritime domain — autonomous systems, electronic warfare, maritime domain awareness, and sovereign AI infrastructure — to ensure American and allied maritime dominance.

Exclusion Criteria

Not generalist defense; no consumer tech, pure commercial software without defense application, or non-maritime-domain investments.

02Investment Team
MB
Marc Baliotti
General Partner
EB
Erik Bethel
General Partner
LS
Lorin Selby
General Partner
VV
Vrushank Vora
General Partner
SG
Solange Guyot
Executive Assistant
03F4 Research Brief

Mare Liberum Research

Overview

Mare Liberum is a defense-focused venture and growth equity fund investing at the intersection of critical technologies and the maritime domain. The firm was formally launched on April 4, 2026, with a $150M anchor facility obtained through the U.S. Small Business Administration's SBICCT (Small Business Investment Company Critical Technologies) program. Mare Liberum is actively raising additional equity capital from institutional investors on top of this government-guaranteed leverage facility.

The fund's name — Latin for "free sea" — reflects its core conviction that the freedom of navigation and control of sea lanes is fundamental to American economic security and geopolitical influence.

Investment Thesis

Mare Liberum positions maritime security and global sea-lane stability as foundational to modern economic prosperity. The firm argues that "the future of global stability is decided at sea," identifying three critical inflection points driving their thesis:

  1. Asymmetric Naval Warfare: Unmanned and autonomous systems are fundamentally reshaping how maritime conflicts are fought, as demonstrated by the use of MAGURA V5 autonomous drones in Ukraine. Traditional naval supremacy can no longer be taken for granted against lower-cost adversarial systems.

  2. Supply Chain Realignment: Global trade is decoupling from China-dependent routes as geopolitical tensions drive reshoring and allied-nation supply chain diversification. Maritime freight carries over 80% of global trade by volume, making this realignment a massive capital deployment opportunity.

  3. Energy Transition & AI Demands: Ocean exploration and subsea infrastructure are increasingly critical for energy supply chains and the fiber cable networks underpinning global AI compute.

The fund targets companies building the software, hardware, and platforms that enable maritime dominance — autonomous systems, domain awareness, sovereign AI infrastructure, and next-generation defense technologies.

Sector Focus

Mare Liberum invests exclusively in the intersection of defense technology and maritime operations:

  • Autonomous Maritime Systems: Unmanned surface vessels, autonomous platforms, underwater drones
  • Electronic Warfare: Directed-energy systems, high-power microwave, counter-UAS
  • Maritime Domain Awareness (MDA): AI platforms fusing AIS, satellite, and sensor data for real-time maritime intelligence
  • Sovereign AI Infrastructure: AI systems for national security and classified government applications
  • Low-Emission Coastal Transport: Electric and hybrid maritime transport for commercial and defense dual-use
  • Resilient Logistics: Supply chain technologies reducing dependency on adversarial infrastructure
  • Advanced Manufacturing & Robotics: Shipbuilding, drone manufacturing, precision manufacturing for defense

The fund's investment universe is tightly scoped to national security relevance — they are not generalist defense investors but specifically focused on the maritime domain.

Stage Focus

Based on the disclosed portfolio, Mare Liberum invests across a range from late Seed through growth equity, with apparent emphasis on companies that have demonstrated product-market fit in defense or commercial maritime markets and are scaling revenue. Portfolio companies like Saronic Technologies (Series D, $9.25B valuation, $392M Navy contract) and Windward (publicly listed maritime AI company) indicate comfort investing at significantly later stages than typical venture funds. REGENT Craft (Y Combinator alumnus backed by Japan Airlines and Alaska Airlines) suggests they also participate in earlier growth rounds.

Check Size

The fund has not publicly disclosed check sizes. With a $150M government-leveraged facility and approximately 5 disclosed portfolio companies, implied average check sizes are in the $20–50M range for growth-stage investments, though earlier-stage deals may be smaller. This is consistent with the SBIC structure which pairs government-backed leverage with equity positions.

Fund Structure & AUM

Mare Liberum operates under the SBA's SBICCT program, which provides up to $150M in low-cost, government-guaranteed leverage to funds investing in critical technologies. The fund combines this leverage with equity capital from institutional investors. Total AUM target was not publicly disclosed at launch. The SBICCT program is designed for funds focused on technologies critical to national security.

Portfolio Highlights

Saronic Technologies (saronic.com): Autonomous surface vessels for maritime security, surveillance, and defense. Based in Texas. Closed a $1.75B Series D at a $9.25B valuation, awarded $392M U.S. Navy contract.

REGENT Craft (regentcraft.com): All-electric Seaglider vessels for fast, zero-emission coastal transportation. Dual commercial/defense use. Backed by Y Combinator, Japan Airlines, Alaska Airlines, Lockheed Martin.

Epirus (epirusinc.com): Directed-energy, high-power microwave (HPM) systems for electronic warfare and counter-UAS. Primary product Leonidas serves government and defense markets.

Windward (windward.ai): AI platform fusing multi-satellite, terrestrial, and AIS data for maritime domain awareness. Serves commercial intelligence, risk/compliance, border security, and defense sectors.

Stealth Incubation: Sovereign AI infrastructure for critical national security applications. Details not publicly disclosed.

Team

Marc Baliotti — General Partner: Extensive background in alternative asset management. Former Senior Managing Director at AE Industrial Partners (Structured Solutions Fund). Previously 13+ years at GSO Capital Partners (Blackstone) as MD in the Performing Credit Group. Earlier: Morgan Stanley, DLJ Merchant Banking, AIG Highstar Capital. Naval Academy alumnus. Served on 20+ company boards.

Erik Bethel — General Partner: 20+ years in global finance. Former Partner at Americas Frontier Fund specializing in deep tech and strategic investments. Formerly U.S. Representative to the World Bank (Senate-confirmed), overseeing $100B+ in capital. Career includes J.P. Morgan, Morgan Stanley, Franklin Templeton. Board member at Windward. Fellow at CSIS. Naval Academy; Wharton MBA.

Rear Admiral Lorin Selby (Ret.) — General Partner: Navy's 26th Chief of Naval Research (~3,800 personnel, $4B budget). Submarine warfare officer and nuclear engineer. First non-Engineering Duty Officer selected as Chief Engineer of the Navy. Commanded USS GREENEVILLE (nuclear fast attack sub). BS Nuclear Engineering (UVA), MS Nuclear Engineering (MIT).

Vrushank Vora — General Partner: Former Partner at America's Frontier Fund (microelectronics and AI focus). Founded two AI supply chain companies — one adopted by Fortune 500, one building tools for the DoD. Among first to productize distributed reinforcement learning. Co-PI for NSF initiative. BS Math/Stats/Econ (University of Chicago), MS CS/ML Systems (Georgia Tech).

Advisory Board

A particularly strong board including: Kenneth Braithwaite (former Secretary of the Navy), Matthew Pottinger (former Deputy National Security Advisor), Paula Dobriansky (former Undersecretary of State for Global Affairs), Timothy Gallaudet (former Head of NOAA and Chief Oceanographer of the U.S. Navy), Louis E. Sola (former Chairman of the Federal Maritime Commission), John Konrad (Founder/CEO of gCaptain).

Geographic Focus

Primarily U.S.-based with a defense contracting orientation. Portfolio companies are U.S.-headquartered with some global commercial traction. Fund aligned with U.S. and allied-nation procurement priorities.

Decision Process

Four General Partners suggest a partnership-based decision process. Deep government and Navy relationships indicate investments often sourced through national security networks and warm introductions within the defense-tech ecosystem.

Founder Preferences

Mare Liberum appears to favor:

  • Technical founders with defense or maritime domain expertise
  • Companies with existing U.S. government revenue or contracts
  • Dual-use technologies serving both defense and commercial maritime markets
  • Founders with national security credibility or prior government/military experience
04Selected Portfolio
Aerospace & Defense
Saronic·Epirus
Enterprise Software
Windward·Stealth Incubation
Logistics & Supply Chain
REGENT Craft
Open the full portfolio→
05Recent Updates

Fresh signals from public announcements, essays, and portfolio activity.

See full activity (5) →
Mare Liberum co-led REGENT Craft's $240M Series B (split $120M equity / $120M debt). Round co-led with AE Ventures, with participation from DCVC, Founders Fund, Lockheed Martin Ventures, Japan Airlines. Debt from Erebor Bank. REGENT is an all-electric seaglider manufacturer for commercial and defense maritime use. This brings REGENT's total funding to over $340M.
INVESTMENT·ventureburn.com
AUG 27, 2026
Listed Stealth Incubation, a sovereign AI infrastructure company for critical national security applications, among select investments.
INVESTMENT·mareliberum.com
Added recently
Lorin Selby delivered remarks on defense technologies at VC Latam Summit.
TALK·df.cl
APR 22, 2026
Discussed maritime venture capital and defense technology investing.
PODCAST·youtube.com
APR 14, 2026
Mare Liberum announced formation of its second fund with up to $150M in low-cost government-guaranteed leverage via the SBICCT program from the SBA and Pentagon's Office of Strategic Capital. The firm is raising additional equity from institutional investors for autonomous maritime platforms, maritime domain awareness, resilient logistics, counter-UAS, and advanced manufacturing investments.
NEW FUND·prnewswire.com
MAR 5, 2026
06Frequent co-investors
N
NightDragon
Both backed 2 of the same companies
Saronic, Epirus
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Quick Reference
Stages
Series B · Series C · Growth
Decision
Partnership
Warm Intro
Preferred
Involvement
Board Seat
Location
Miami, FL
Sector Focus
Aerospace & DefenseLogistics & Supply ChainRobotics & Automation
Models
Defense TechDual-Use TechnologyGovernment Contracting
Technology
Autonomous SystemsAI/MLDirected Energy
See all Aerospace & Defense investors →See all Logistics & Supply Chain investors →See all Robotics & Automation investors →
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Focus Areas
Aerospace & DefenseLogistics & Supply ChainRobotics & Automation

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F4 Intelligence Report · Last Researched September 18, 2026F4 Research Engine