What is a transition bond? SEBI's GB-T rules

A transition bond is the awkward middle of India's green bond rulebook. A solar plant is obviously green. A cement or steel plant cutting its emissions is not green, but the money it needs to get cleaner still has to come from somewhere. SEBI's answer was to make transition bonds a sub-category of green debt security, with a distinct denotation and an extra disclosure package attached. This guide covers what a transition bond is, why it is tagged GB-T, what has to go in the transition plan, and what the issuer keeps reporting afterwards. It is not investment advice.

What is a transition bond under SEBI rules?

The definition is short and it turns on one external reference. India's Intended Nationally Determined Contributions, per the explanation printed in the regulation itself, are the climate targets India set under the Paris Agreement at the Conference of Parties 21 in 2015 and at the Conference of Parties 26 in 2021, as revised from time to time. So a transition bond is not measured against a generic idea of getting greener. It is measured against a national commitment, and the offer document has to show the alignment: Chapter IX paragraph 1.2(d) requires details of how the objective of the issue aligns with India's Intended Nationally Determined Contributions where the proceeds are raised through transition bonds.

Everything that applies to a green debt security applies here first. The thirteen eligible categories, the initial disclosures, the audited utilisation reporting and the external reviewer are all set out in what are green debt securities. Chapter IX-B of SEBI's Master Circular for issue and listing of non-convertible securities, securitised debt instruments, security receipts, municipal debt securities and commercial paper, dated 15 October 2025, then adds the transition-specific layer on top.

Why are transition bonds tagged GB-T?

Because without a tag they are indistinguishable from any other green bond in a database, and they carry a different kind of claim. A green bond says the proceeds fund something already clean. A transition bond says the proceeds fund something getting cleaner, on a stated timeline, from a stated starting point.

SEBI's fix is a denotation that travels with the instrument through three places. It goes on the cover page of the offer document. It goes in the type of instrument field of the term sheet. And it goes into the Centralised Database for corporate bonds and debentures, where the issuer fills GB-T under the "Others (please specify)" sub-point of the type of instrument field, and the depositories prefix GB-T in the instrument details field.

That third placement is the one that matters for anyone tracking this data rather than reading a single prospectus. The denotation sits in a structured field in a central database, keyed to the instrument, which is what makes transition bonds separable from the rest of the green universe at all.

What goes in the transition plan?

The transition plan is the substantive disclosure, and Chapter IX-B paragraph 2.1.2 lists four components.

1. Interim targets and milestones, with an indicative timeline for achieving them. A note attached to that item adds that interim targets should also reflect an indicative figure for how much emissions the issuer envisages reducing. A plan without a number is not a plan under this clause.
2. A brief of the project implementation strategy.
3. Details of the technology used for implementing the project.
4. A mechanism to oversee the utilisation of the funds raised and the implementation of the plan. The circular suggests, without mandating, that issuers may form a committee to oversee implementation and ensure the defined targets are met on time.

What continues after listing?

Two ongoing obligations, plus exchange monitoring.

If the transition plan is revised during the year, the issuer discloses the revised plan to the stock exchanges along with an explanation for the revision. That is the clause that makes a slipped target visible rather than silently restated at year end.

In the annual report, the issuer discloses the transition plan along with a brief on progress of implementation. Stock exchanges are directed to monitor both the mid-year revision disclosures and the annual report disclosures.

Alongside these, the general green debt security obligations continue: the externally audited utilisation of proceeds, unutilised proceeds by ISIN, project-by-project impact reporting, and the Business Responsibility and Sustainability Reporting elements described in what is BRSR.

How does this differ from a sustainability-linked bond?

Both instruments deal with an issuer that is not yet clean, and they solve it differently. A transition bond is a use-of-proceeds instrument: the money is ring-fenced for the transition, and the plan describes what gets built. A sustainability-linked bond does not ring-fence anything; instead its financial or structural terms move with the issuer's performance against predefined targets. That distinction, and the separate rulebook that governs it, is covered in what is a sustainability-linked bond and in green bonds vs sustainability-linked bonds.

A transition bond is the one green debt security where the disclosure carries a forward-looking promise rather than a completed project, which is exactly why SEBI attached a denotation, a dated plan and a revision-disclosure duty to it. Flock reports public regulatory filings with every claim sourced and dated. What any of it means for your money is your call to make.