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Warm Fund

43 Fund

43.io

“Anabel Paksoy actively looks to invest in early-stage startups at Day 0, providing hands-on support tailored to the founder's unique needs. She focuses on founders who are passionate about solving specific problems, and investments are made quickly to take advantage of timely opportunities.”

$250K – $500K
Check Size
Leads
Lead Tendency
01Investment Thesis

Anabel Paksoy actively looks to invest in early-stage startups at Day 0, providing hands-on support tailored to the founder's unique needs. She focuses on founders who are passionate about solving specific problems, and investments are made quickly to take advantage of timely opportunities.

02Founder Preferences

Preferred founders are those who are deeply invested in the problems they are addressing, and ideally seek support even before they transition from their current roles.

03Investment Team
AP
Anabel Paksoy
04F4 Research Brief

43 Capital: Anabel Paksoy Investment Profile

Fund Overview

43 is an earliest-stage venture capital fund founded by Dustin Dolginow, Anabel Paksoy, and Soso Sazesh. The firm specializes in Day 0 pre-product investments, providing $250K-$500K initial checks to founder-obsessed teams before they have launched products or achieved market traction.

Investment Philosophy & Thesis

43's core thesis centers on the founder-first approach: the team invests with conviction in approximately 5 founders per partner per year. Their philosophy emphasizes speed, conviction, and bespoke support rather than batch programs or generic scaling models.

Key thesis elements:

  • Founders obsessed with solving a problem (not optimizing for capital)
  • Day 0 stage investments, often meeting founders before they've left their jobs
  • No product or traction required
  • Speed as a competitive advantage (2-4 week process from conversation to funding)
  • Hands-on, personalized support from operators with extensive exit experience

Investment Check Sizes & Deployment

  • Initial check range: $250K-$500K
  • Check size flexibility: Tailored to founder needs and runway requirements
  • Deployment pace: ~5 investments per partner annually (15-20 total portfolio per year at 3-person firm)
  • Fund status: Actively deploying as of late 2025

Stage Focus

  • Primary: Pre-seed/Seed (Day 0, pre-product)
  • Secondary: Extended runway founders transitioning out of jobs
  • No demo days, batches, or structured cohorts—entirely bespoke relationships

Team & Backgrounds

Dustin Dolginow (Managing Partner)

  • Previously at Accomplice and Maiden Lane
  • Early-stage investor track record: Roofr, Baseten, Klaviyo, Notion, Vercel, Reside, CodeSignal
  • Operational operator with deep network across consumer and SaaS

Anabel Paksoy (Partner)

  • Formerly Head of People Operations at Opendoor and Twitter
  • Founded The People Design House (people operations advisory)
  • Advisors at: Notion, Pave, Syndicate
  • Angel investor: Newfront, TRM Labs, Portex
  • Brings HR/operations expertise and deep operator network

Soso Sazesh (Partner)

  • 2X founder with successful exit
  • Operational advisor to growth-stage companies: Instacart, Gusto, Zapier, Klaviyo, and dozens of others
  • Brings founder perspective and scaling experience

Portfolio Composition & Revealed Preferences

Analysis of 70+ portfolio companies reveals strong concentration in:

Sector patterns:

  • B2B SaaS: FlowFi (accounting), Supademo (product demos), CollabWork (collaboration), Lace (operations)
  • AI/ML: Kaiden AI, Flotive (AI aviation), Standard Works (AI), Supercreator (AI content), DataInsight (AI analytics)
  • Vertical SaaS: Headcount365 (HR), Secludy (security), Sharebird (sales enablement), PressBox (PR)
  • Hardware/Dev Tools: tscircuit (electronics), Nema Systems (systems), Kit Switch
  • Healthcare/Healthtech: Insight Health (AI health), Dart Health (healthcare), Harness (insurance)
  • Workflow automation: ProjectUs, Time-line, Word Chef, Shipflow AI
  • Fintech-adjacent: GiveCard, FlowFi

Support Model & Thesis on Value-Add

43 explicitly rejects batch-model acceleration. Value proposition:

  • 1:1 bespoke support: Each partner works closely with ~5 founders annually
  • Strategic guidance: No generic advice; tailored to founder's specific challenges
  • Network introductions: Access to 43's extended operator network
  • Operational support: Leveraging team's deep operational experience in People/Growth/HR
  • Fundraising preparation: Help structuring for next institutional round
  • Speed advantage: 2-4 week decision timeline, enabling faster market entry

Investment Process & Decision-Making

  • Application: No pitch deck required; focus on founder vision and background
  • Timeline: 2-4 weeks from initial conversation to funding
  • Due diligence: Emphasis on founder conviction and obsession over market validation
  • Decision criteria: Problem obsession, founder quality, team chemistry
  • Process philosophy: Human judgment and founder relationship over metrics/scoring

Recent Activity & Fund Status

  • Active stage: Actively deploying capital (confirmed through 2025 Tracxn data)
  • 2023 positioning: 9 investments mentioned in Anabel's Jan 2023 announcement introducing 43
  • 2025 activity: Continued investment in Day 0 founders; confirmed by Recast Accelerate participation
  • Institutional recognition: Featured in Recast Capital's startup fund accelerator cohort (Sep 2025)

Geographic & Model Preferences

  • Geography: Primarily SF Bay Area operators and founders; some national presence
  • Model: B2B SaaS dominant, strong AI/ML subset, vertical-specific solutions
  • Stage extension: Some follow-on capacity visible; not pure pass-through fund
  • International: Minimal (no clear non-US portfolio companies observed)

Partner Availability & Lead Tendency

Given firm size (3 partners) and investment tempo (~5 per partner/year), individual partners can be selective with ~1 new investment every 2-3 months. Primary partner involvement in structured process is typical.

Anti-Thesis

43 explicitly avoids or is less interested in:

  • Companies with product-market fit already achieved (more Series A+)
  • Teams seeking generic support or batch programs
  • Founders not obsessed with their problem
  • Pure financial engineering plays
  • Batch demo days or cohort-based acceleration

Fund Economics

  • Check size: $250K-$500K = ~5-7% ownership typically
  • Fund capacity: Small fund size with concentrated portfolio limits deployment
  • Follow-on rights: Visible in some portfolio companies; not purely seed-and-exit
05Selected Portfolio
AgTech & Agriculture
Leaficient
Biotech & Life Sciences
ProjectUs
Developer Tools & Infrastructure
Supercreator·Ensemble Technologies·Trades·tscircuit
E-commerce & Marketplaces
Loma·Lace·Tato
Enterprise Software
Supademo·Clued·Kaiden AI·Shipflow AI·BuildVision·Standard Works·Flotive·Riza·Grid·Harness
Fintech & Payments
GiveCard·FlowFi·Embed
Healthcare & Digital Health
Dart Health·Insight Health·Vim
HR Tech & Future of Work
CollabWork·headcount365
Marketing & Adtech
Word Chef·Sharebird·Rythm
Media & Entertainment
PressBox·Hypernatural·Noble Machines·Time-line
Real Estate & PropTech
Kit Switch·UCR
Robotics & Automation
Nema Systems
Security & Cybersecurity
Secludy
Open the full portfolio→
06Recent Updates

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

Participated in Insight Health's $11M Series A for clinical AI agents.
INVESTMENT·businesswire.com
APR 3, 2026
Led Hypernatural's seed round ($2.4M) for AI video creation.
INVESTMENT·businessinsider.com
JUL 23, 2025
Led Riza's seed round ($2.7M) for AI-first code execution infrastructure.
INVESTMENT·techfundingnews.com
APR 16, 2025
07Frequent co-investors
SC
Script Capital
Both backed 3 of the same companies
Insight Health, Secludy, Clued
BF
Basecamp Fund
Both backed 2 of the same companies
Embed, Insight Health
CC
Crosslink Capital
Both backed 2 of the same companies
BuildVision, Harness
Find the investors for your round→
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Quick Reference
Check Size
$250K – $500K
Stages
Seed · Pre-Seed
Decision
Partnership
Sector Focus
Fintech & PaymentsReal Estate & PropTechInsuranceLogistics & Supply ChainEdTechRobotics & AutomationEnterprise SoftwareDeveloper Tools & InfrastructureMedia & EntertainmentHealthcare & Digital Health
Models
B2B SaaSVertical SaaSWorkflow AutomationAI/MLHealthcare Tech
Technology
AI/MLSaaS PlatformDeveloper ToolsAutomation
See all Fintech & Payments investors →See all Real Estate & PropTech investors →See all Insurance investors →
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Focus Areas
Fintech & PaymentsReal Estate & PropTechInsuranceLogistics & Supply ChainEdTechRobotics & AutomationEnterprise SoftwareDeveloper Tools & InfrastructureMedia & EntertainmentHealthcare & Digital Health

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F4 Intelligence Report · Last Researched August 2, 2026F4 Research Engine