---
agentTools:
  projectIndex: https://ror.readme.io/llms.txt
---

# 2026-05-26 Default affiliation matching strategy is now single search

**Starting May 26th, the `?affiliation` parameter of the ROR API uses the new "single search" strategy by default.**  This is not a breaking change, and the legacy "multisearch" strategy can still be used if desired, as described below and in the [Affiliation parameter](https://ror.readme.io/docs/api-affiliation) documentation.

## Background

ROR developed and rigorously tested the "single search" matching strategy in conjunction with Crossref. <Anchor label="OpenAlex adopted the strategy soon after it was published" target="_blank" href="https://doi.org/10.71938/mtx2-vb16">OpenAlex adopted the strategy soon after it was published</Anchor>, and it is being used as the basis for a forthcoming <Anchor label="Crossref initiative to match funder names to ROR IDs" target="_blank" href="https://doi.org/10.64000/d3f5t-g5017">Crossref initiative to match funder names to ROR IDs</Anchor>. The single search strategy outperforms the previous ROR multisearch matching strategy in both precision and recall while also being more computationally efficient.

In December 2025, we announced <Anchor label="the implementation of the single search matching strategy" target="_blank" href="https://doi.org/10.71938/zz90-g810">the implementation of the single search matching strategy</Anchor> as an option for matching text strings to ROR IDs with the [Affiliation parameter](https://ror.readme.io/docs/api-affiliation) of the ROR API, and we have now made single search the default.

## Query formats

If you wish, you can specify the matching strategy you want to use for programmatic matching of text strings to ROR IDs. If no strategy is specified, the affiliation parameter will now use the single search strategy by default.

**Default - single search**

`https://api.ror.org/v2/organizations?affiliation=[URL-encoded-string]`

**Specify single search**

`https://api.ror.org/v2/organizations?affiliation=[URL-encoded-string]&single_search`

**Specify multisearch**

`https://api.ror.org/v2/organizations?affiliation=[URL-encoded-string]&multisearch`

## Learn more

For more details, read the [Affiliation parameter](https://ror.readme.io/docs/api-affiliation) documentation or the <Anchor label="launch announcement for the single search matching strategy" target="_blank" href="https://doi.org/10.71938/zz90-g810">launch announcement for the single search matching strategy</Anchor>.

For help, contact <support@ror.org>.