See other companies on Otta


Direct air carbon capture

101-200 employees
  • B2B
  • Sustainability
  • Environmental
  • Science
Dogpatch, San Francisco, CA

Company mission

To help build a more resilient and equitable future.

Top investors

66% employee growth in 12 months

Otta's take

Xav Kearney headshot

Xav Kearney

CTO of Otta

According to the UN, in order to avoid climate disaster the world needs to both reduce carbon emissions and actively remove CO₂ from the atmosphere. Heirloom develops a technology to handle the latter, using limestone to capture carbon directly from the air and permanently store it - and in doing so delivering high-quality carbon credits for businesses to purchase.

Initially, the company stored captured carbon in underground deposits, but it now also boasts the ability to sequester CO₂ into concrete. This process, which was developed alongside its partner, CarbonCure, actually strengthens the concrete, which can then be used in all types of construction projects.

Crucially, because limestone is so widely available - and because the capture process is a chemical reaction - the process requires minimal land and energy. This allows the company to remain relatively low-impact in its operations, making its carbon removal credits more valuable. This has contributed to the achievement of Microsoft purchasing 315,000 metric tons of carbon removal from the company, in one of the biggest deals of its kind to date.


  • Generous stock options
  • Unlimited PTO for salaried employees & 80 hours for full time hourly employees
  • 401(k)
  • Monthly health and wellness reimbursement
  • Robust annual education and conference budget, including airfare and hotel costs
  • Excellent health, dental and vision insurance covered up to 100% by Heirloom (FSA option)
  • 16 weeks paid leave for all Heirloom employees, regardless of primary/secondary caregiver status

Company values

  • Radical Honesty: Bottom line - we are open, transparent, and inclusive in everything we do. We aren't scared to challenge each other, but bring clear motives and our best intentions when we do
  • Persistent Optimism: We carry an infinite amount of optimistic energy with us on our journey, constantly chipping away at what may seem insurmountable
  • Maximize Learning Rate: Compounding knowledge is our key to victory - we continuously hone our crafts, seek the fastest paths to new learning, and are quick to absorb new knowledge

Funding (2 rounds)

Mar 2022



May 2021




Total funding

This company has top investors


Previously founded Tempo Automation, a robotics and software company that raised millions in funding from venture capitalists.

Noah McQueen

(Head of Research)

Earned a PhD in Chemical Engineering from the University of Pennsylvania. Worked as a Science Advisor at Carbon Direct for a year.

Jobs (4)

All locations

Software Engineering

People, HR, Recruitment

Sales & Account Management