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Third Sphere | RoundOS

01 · Free data roomBuild, share and track important documents.

Data room analytics Document Analytics Pitch Deck Tracking Secure sharing Permissions NDA & agreements Watermarking Versions Branding

View all Data Room features →

02 · AI Fundraising CRMRun the work between investor meetings.

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View all Operator features →

See it workingOpen a live roomWalk a real RoundOS room.

Pricing Security

Deal rooms

Startups Venture capital M&A data room Investor relations

Beyond fundraising

Sales deals Board documents Due diligence Real estate

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Fundraising hub Pre-seed Seed Series A

Learn

Blog Funding Customer stories Investor room template

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All alternatives Best free data rooms Best DocSend alternatives Digify alternative iDeals alternative

Free tools & templates

Calculators and fundraising tools. No signup.

SAFE, dilution, runway, pipeline coverage, investor fit.

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TS

Third Sphere

Activity from announced rounds

Activity in this selection View all activity

All recorded activity

Rounds participated in: 2
Confirmed lead rounds: —
New companies: 2
Funding in participating rounds: $30M

By stage

Seed1

Series A1

By primary sector

Climate tech1

Industrial tech1

By country

United Kingdom1

United States1

Rounds

2 in all activity

Aug 19

Sonic Fire Tech

Develops infrasound-based fire suppression technology inspired by aerospace research

$15MSeed

Role not disclosed

Mar 4

Develops bio-based plastic alternative materials for packaging and consumer goods

$15MSeries A

Role not disclosed

1–2 of 2

Most frequent co-investors

AirAngels1 shared alter equity1 shared Founder Collective1 shared JamJar1 shared Khosla Ventures1 shared LocalGlobe1 shared NFDG1 shared The O.H.I.O. Fund1 shared

RoundOS

A free data room for modern deals, with an AI operator that runs the fundraise.

Create a free room

01 · Explore

Data Room AI Fundraising CRM Pricing Security Document Analytics Pitch Deck Tracking

02 · Data Room

Data room analytics Secure document sharing Data room permissions NDA & agreements Dynamic watermarking Document versions Custom branding

03 · Operator

Fundraising hub Pre-seed fundraising Seed fundraising Series A fundraising Fundraising follow-up Investor research Investor updates Integrations

04 · Use cases

Startup data room VC and LP data room M&A data room

Pitching Third Sphere? Send the deck from a free RoundOS data room and see which pages they read.

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Due diligence data room

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05 · Free tools

All free tools SAFE calculator Dilution calculator Runway calculator Pipeline coverage Investor fit checker Follow-up generator Round leak audit

06 · Resources

All alternatives DocSend alternative Digify alternative Google Drive alternative Dropbox alternative Best DocSend alternatives Best free data rooms Investor room template Blog Customer stories Funding News Open a live room

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