Third Sphere describes itself as a climate-focused venture fund investing at pre-seed and seed, typically writing initial cheques of $250,000 to $1 million and reserving follow-on capital. It says about 80 percent of its portfolio is hardware-enabled, usually with a software component, and that roughly two-thirds of the portfolio is focused on mitigation, mostly via electrification, with one-third on resilience and adaptation. It states it is primarily US-focused while having backed teams in Switzerland, Germany, Israel, the United Kingdom and South Africa. It runs a stated 'seedstrapping' model in which it invests $250k to $1m, earmarks up to $2m more for a following round, and works with founders over six months toward $1m ARR or $10m in pre-orders. It says it holds some board seats but generally prefers board observer and information rights.
$50-99M (total assets under management, the range as published in the ImpactAssets IA 50 2023 manager profile; the firm publishes no point AUM figure of its own) AUM66/100 Power Score™2013 FoundedLos Angeles, CA
The firm begins as Urban Us, in its own words to 'combat climate change by reimagining and upgrading our cities'.
2016
Urban Us Fund II, LP files a Form D from a Miami Beach, FL address on 26 January 2016.
2017
The firm builds and operates the URBAN-X accelerator, which it ran from 2017 to 2021.
2019
Urban Us Fund III, LP files a Form D from a Brooklyn, NY address reporting a $45,000,000 offering with a first sale on 18 March 2019.
2021
URBAN-X concluded in December 2021, per the firm's own funds page.
2022
Urban Us renames itself Third Sphere, announced by co-founder Shaun Abrahamson on 27 February 2022 and reported by TechCrunch on 1 March 2022.
2022
Third Sphere Fund IV, LP files a Form D from a Los Angeles, CA address on 20 May 2022 reporting a $100,000,000 offering, $9,875,000 sold, first sale 6 May 2022.
2025
The firm reports three portfolio M&A exits in its 9 October 2025 update: Firmus to Bluebeam, Rachio to Rain Bird, and Urbint to Itron.