# Overview of Carbon Classes

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Carbon classes define eligibility and execution parameters only. They do **not** create fungible financial instruments, redemption rights, or secondary trading markets.
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### What Is a Carbon Class?

A carbon class groups carbon credits with sufficiently similar characteristics to enable structured intake and retirement under shared execution terms.

Credits within a class must share relevant attributes, such as:

* Methodology
* Technology type
* Certification standard
* Geography
* Vintage
* Registry

Classes allow comparability across credits while preserving project-level specificity.

Suppliers and buyers interact with the protocol through these classes:

* **Suppliers:** Provide eligible tokenised credits into a class at the prevailing execution rate.
* **Buyers:** Access credits from a class for irreversible retirement at the prevailing execution rate, either directly or via third-party interfaces.

<figure><img src="/files/YDyGnFj7FrmUA6rl7bVC" alt=""><figcaption></figcaption></figure>

Although classes standardise execution terms, users may select specific underlying credits within the class when supplying or retiring.

For example, a carbon supplier holding Biochar Project 1, could supply that credit to the Biochar carbon class if they are happy with the current execution terms, without needing to hold Biochar Project 2 or 3. Similarly, a user looking to retire carbon credits could choose to retire Biochar Project 3 only (i.e. they would not  to receive a randomised unit from within the class).<br>

<figure><img src="/files/aFuXQX1XHmL1CmGJOrgO" alt="" width="563"><figcaption></figcaption></figure>

### Dynamic Structure

Carbon classes are not static. They may evolve to reflect changes in methodologies, registries, or market conditions.

For example:

* A new methodology may be added to an existing class.
* A methodology may be deprecated for future intake while existing inventory remains eligible for retirement.
* A new class may be created to separate credits previously grouped together.

Changes affect eligibility for future intake. Credits already held by the protocol remain available only for retirement.

***

### Whitelisting Framework

Whitelisting determines which credits are eligible for protocol intake under a given carbon class.

Whitelisting may involve:

* Creating a new carbon class
* Adding credits to an existing class
* Restricting new intake for specific credits

Eligibility criteria may include:

* Certification standards
* Methodology relevance
* Vintage parameters
* Geography
* Public issuance and retirement data
* Registry approval for blockchain integration

Note: All integrated credits require explicit permission from the originating registry to mitigate double-counting risk and ensure compliance with registry terms.

***

### Governance & Process

The initial whitelisting process will involve consultation with ecosystem partners. Proposals and feedback will be documented publicly.

Over time, governance mechanisms may incorporate structured token-based coordination.

All proposals, feedback, and decisions will be published prior to implementation to maintain transparency.

***

### Carbon Classes at Launch

<table data-full-width="false"><thead><tr><th width="280.4000244140625">Carbon class</th><th width="294.60009765625">Whitelisted projects</th><th align="right">Liquidity at Launch</th></tr></thead><tbody><tr><td>Ocean Alkalinity Enhancement</td><td>Limenet – CMARK02</td><td align="right">~14 tonnes</td></tr><tr><td>Biochar</td><td><p>PUR-527-2023</p><p>PUR-718-2024</p></td><td align="right">~100 tonnes</td></tr><tr><td>Avoided Deforestation</td><td><p>ECO-22</p><p>ECO-114</p></td><td align="right">~20,000 tonnes</td></tr><tr><td>Regen – City Forest Credits</td><td><p>REGEN-C02003-2022</p><p>REGEN-C02004-2021</p><p>REGEN-C02006-2022</p></td><td align="right">~2,000 tonnes</td></tr><tr><td>UCR - Solar</td><td>UCR-80-2021
<br>UCR-170-2021
<br>UCR-81-2021
<br>UCR-50-2021
<br>UCR-433-2023
<br>UCR-367-2022
<br>UCR-420-2023
<br>UCR-356-2022
<br>UCR-419-2023
<br>UCR-285-2023
<br>UCR-436-2023
<br>UCR-438-2023
<br>UCR-437-2023</td><td align="right">~87,000 tonnes</td></tr><tr><td>UCR - Wind</td><td>UCR-121-2022
<br>UCR-341-2022
<br>UCR-150-2021
<br>UCR-320-2022
<br>UCR-164-2022
<br>UCR-423-2022</td><td align="right">~254,000 tonnes</td></tr></tbody></table>

### Current Carbon Class Data

Up-to-date information concerning current carbon liquidity, carbon classes, carbon credit retirement data, and more, is accessible via our Ecosystem Dashboard. *Note that this dashboard is currently being relaunched--a link will be provided here once that process is completed.*&#x20;


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