- Alt Carbon becomes the world’s largest (Enhanced Rock Weathering) ERW company by total verified issuance, with 9,566 tonnes removed across the Darjeeling Revival Project
- Alt Carbon’s cumulative ERW issuance now exceeds any other verified ERW issuances globally.
- Credits delivered to a growing portfolio of world-class buyers including the Frontier coalition of buyers: Stripe, Google, Shopify and Match Group through Watershed. Buyers also include, NextGen CDR, CEEZER — marking the mainstreaming of ERW as a high-integrity CDR pathway
- Alt Carbon’s portfolio of global buyers now span tech, finance, & shipping, removing CO₂ durably and permanently.
Bangalore, India — 27th May 2026: Alt Carbon, a Planetary Intelligence startup, today announced that it has generated 9,566 tonnes of verified carbon dioxide removal (CDR) credits making it the world’s largest Enhanced Rock Weathering (ERW) company by volume of issued credits.
This milestone marks deliveries to some of the world’s leading buyers of carbon removal. These include the Frontier coalition of buyers: Stripe, Google, Shopify and Match Group through Watershed. Additional buyers also include marketplaces like CEEZER and a number of undisclosed buyers. Deliveries were also facilitated to the South Pole and Mitsubishi-led coalition NextGen CDR, including other undisclosed buyers.
The breadth of buyers span technology, finance, shipping, commodity traders, aviation, and AI Hyperscalers reflecting a broader shift in how the market views ERW: a scientifically rigorous and scalable pathway for high-integrity carbon removal. Alt Carbon’s cumulative ERW issuance now exceeds all other verified ERW issuances globally.
The CDR market has grown from $300 million to over $12 billion in transacted volumes in the last three years. Yet verified, delivered tonnes remain the exception rather than the rule. The gap between offtake commitments and actual deliveries is one of the most persistent credibility challenges in the voluntary carbon market. Alt Carbon’s third consecutive delivery, and its first to a portfolio of buyers spanning multiple sectors and geographies, is a direct answer to that gap.
Alt Carbon has also reserved a portion of its verified Carbon Credit inventory for the Alt Explorers program — a bespoke executive education and immersion program designed for senior decision-makers across sustainability, marketing, and finance. This invite-only program offers first-hand exposure to Alt Carbon's field operations, laboratory infrastructure, and science methodology to better understand negative emissions technologies, and advance the market. Companies can express their interest here altcarbon.com/remove-co2.
Following independent verification by an accredited Validation and Verification Body (VVB), Alt Carbon's credits have been issued on the Isometric Registry, covering multiple crop types, soil geographies, and growing seasons. CO₂ has been removed from heritage tea estates, rice paddies and diverse agricultural networks across the Darjeeling and Terai regions in India. 9,566 tonnes of CO₂ removed is roughly equivalent to the annual emissions of a small AI data centre running 24/7.
ERW works by spreading waste basalt across agricultural land, where it reacts with CO₂ dissolved in rainwater to form stable bicarbonate ions — carried through river systems to the ocean and stored as calcium carbonate for over 10,000 years. The process simultaneously improves soil health, pH balance, and crop yields for participating farmers.
The science behind the scale: Planetary Intelligence
Alt Carbon’s ability to issue and deliver CDR credits at this volume is underpinned by a scientific infrastructure built over the last two years. The company’s two laboratories — Shonku Labs at the Indian Institute of Science (IISc) campus in Bangalore, and the Darjeeling Climate Action Lab (D-CAL), a 15,000 sq. ft. facility in the foothills of the Himalayas — together can process over 100,000 samples annually. They have analysed more than 20,000 samples to date, operating one of the highest-throughput ERW sample analysis facilities in India.
To understand the scale of what this represents: Europe’s LUCAS Soil Survey — one of the most ambitious undertakings in the history of Earth Sciences, coordinated across 25 EU member states with hundreds of surveyors and years of institutional planning, collected roughly 20,000 harmonised soil samples. It was described in peer-reviewed literature as the largest harmonised open-access soil dataset available for the European Union. Alt Carbon’s science team generated 12,000 ICP-OES analysed samples in eight weeks — 60% of Europe’s landmark survey, from a single project in Darjeeling.
Every sample was prepared by hand, burned in a plasma torch operating at temperatures between 6,000 and 10,000°C, and read at parts-per-billion precision. Alt Carbon also voluntarily sent a portion of its samples to an independent third-party laboratory for cross-validation to bring about accountability and transparency in our work. The protocol does require this, but it foolproofs our carbon removal infrastructure.
Ongoing academic collaborations with IISc, North Bengal University and Ashoka University continue to deepen the scientific foundation underlying each delivery.
Quotes
“Our labs are now equipped to do what national geological surveys take years to build. We processed 12,000 soil samples in eight weeks with the same precision used to analyse meteorites and verify semiconductor-grade metals. We sent a percentage of samples to an external lab to challenge our own numbers. More than the throughput cadence of our labs, this is a maturity story; for our science, our teams, and for ERW as a pathway. The geochemistry of weathering and understanding CO₂ removal is hard. But the compounding of three deliveries, each larger than the last, is proof that we have built something real and repeatable from India’s soil.”
— Shrey Agarwal, Co-Founder and CEO, Alt Carbon
"We're very happy to see Alt Carbon deliver credits against our contract, and the scale of this overall credit issuance makes it all the more significant. Nearly 10,000 tonnes of verified removals shows Alt Carbon's promise, and the progress of the ERW field as a whole."
—Mitch Selby, Sustainability Fund Lead, Shopify
"This issuance from the Monsoon Harvest project is the largest single Enhanced Weathering deployment Isometric has certified to date, and a marker of how the pathway is moving from pilots to delivery. Enhanced Weathering has come a long way in a short time, and issuances at this scale are part of what that growth looks like in practice."
— Tom Sellers, Head of Registry Operations, Isometric
"Enhanced Rock Weathering (ERW) exemplifies the scientifically rigorous and scalable pathway that the durable CDR market needs to mature. At CEEZER, we are seeing a clear shift in buyer appetite toward projects anchored in robust, transparent monitoring and measurement frameworks. This milestone is a powerful signal that open-system carbon removal is no longer just a future promise—it is delivering real, high-integrity assets to the market today."
— Lucas van Doorn, Sourcing and Supply Lead, CEEZER
“Alt Carbon is based out of the foothills of the Himalayas. Our aim is to channel Himalayan Ambitions to undertake moonshot science from India, for the world. With Carbon Removal reaching scale, our work is just getting started. We are excited to undertake more R&D between our frontier labs in Darjeeling and our academic collaborations across IISc and Ashoka.”
— Sparsh Agarwal, Co-Founder and President, Alt Carbon
Notes to the Editor
For further information, please contact the Alt Carbon press office:
Adithya Venkatesan — [email protected]
About Alt Carbon
Alt Carbon is a deeptech science and data company, building infrastructure for Planetary Intelligence. We aim to make South Asia a hub for Carbon Dioxide Removal (CDR) through technology pathways like Enhanced Rock Weathering and Biochar. We work with farmers and scientists in the Global South, to turn underutilized land into carbon sinks. Our flagship initiative, the Darjeeling Revival Project (DRP), is a first-of-its-kind effort to unite climate action with cultural and ecological restoration — by reviving degraded soils, restoring livelihoods, and rebuilding ecosystems. We also launched the Bengal Renaissance Project (BRP), an industrial biochar program that is building a network of biomass banks, and pyrolysis and gasification plants across Eastern India, with a mission to weave hope back into the lands of India.
Alt Carbon is based out of Bangalore/Darjeeling & was founded by tea planter siblings Sparsh & Shrey Agarwal. Our latest seed round for $12m was led by Lachy Groom.
For more information please visit https://www.altcarbon.com/ or follow via LinkedIn or X
