What is the effect of a revision or withdrawal of an approved methodology on registered project activities using that methodology?

Revisions and withdrawals of approved methodologies do not affect:

  • Project activities that, at the time of the revision or withdrawal, have already been registered using the old methodology; or
  • Project activities that, at the time of the revision or withdrawal, have already been published for public comments (as part of the validation process) using the old methodology, but only if the project is then submitted for registration within 8 months of the date of the revision or withdrawal.

This rule was first set out in 3/CMP.1, Annex, paragraph 39:

A revision of a methodology shall be carried out in accordance with the modalities and procedures for establishing new methodologies as set out in paragraph 38 above. Any revision to an approved methodology shall only be applicable to project activities registered subsequent to the date of revision and shall not affect existing registered project activities during their crediting periods (3/CMP.1, Annex, paragraph 39).

Clarification on this decision was provided by the Executive Board at EB 35:

  1. In accordance with paragraph 39 of the CDM modalities and procedures, any revision to an approved methodology or tool referred to in a methodology shall only be applicable to project activities registered after the revision and shall not affect
    1. registered CDM project activities during their crediting period; and
    2. project activities that have been published for public comments for validation using the previously approved methodology or tool, so long as the project activity is submitted for registration within 8 months of the effective date of the revision.
  2. Likewise, if the revision results in the withdrawal of one or more approved methodologies, the withdrawal shall not affect
    1. registered CDM project activities during their crediting periods; and
    2. project activities that have been published for public comments for validation using the previously approved methodology or tool, so long as the project activity is submitted for registration within 8 months of the effective date of the revision (EB 35, Annex 13, paragraphs 16 and 17).

The same rule applies to small-scale projects:

The revision of an approved SSC methodology or tool referred to in a SSC methodology shall not affect (i) registered CDM project activities during their crediting period; and (ii) project activities that have been published for public comments for validation using the previously approved methodology or tool, so long as the project activity is submitted for registration within 8 months of the date when the revision became effective (EB 34, Annex 7, paragraph 14).
In case the revision results in the withdrawal of existing approved SSC methodologies the withdrawal shall not affect (a) registered CDM project activities using the withdrawn methodologies during their crediting period; and (b) project activities that have been published for public comments for validation using the previously approved methodology or tool, so long as the project activity is submitted for registration within 8 months of the date when the revision became effective (EB 34, Annex 7, paragraph 15).

and also to afforestation and reforestation (A/R) projects:

Any revision to an approved methodology shall only be applicable to project activities registered subsequent to the date of revision and shall not affect existing registered project activities during their crediting periods (5/CMP.1, Annex, paragraph 14).

and small-scale A/R (SSC A/R) projects:

Any amendments made to appendix B shall apply only to small-scale afforestation and reforestation project activities under the CDM which are registered subsequent to the date of amendment and shall not affect already registered small-scale afforestation and reforestation project activities under the CDM during the crediting periods for which they are registered (6/CMP.1, Annex, paragraph 10).

The clarification in EB 35, Annex 13 set out above, which clarifies the position in relation to withdrawal of methodologies, is expressed to apply mutatis mutandis to A/R projects.