diff --git a/implementations.md b/implementations.md
index 9390f231..e17c0f5b 100644
--- a/implementations.md
+++ b/implementations.md
@@ -64,7 +64,7 @@ Validators
- json-schema (implementation based on the org.json API) - *supports version 4* (Apache License 2.0)
- json-schema-validator - *supports version 4* (Apache License 2.0)
- JavaScript
- - ajv for Node.js and the browser - *supports version 4, validation keywords and $data reference from [version 5 proposals](https://github.com/json-schema/json-schema/wiki/v5-Proposals)* (MIT)
+ - ajv for Node.js and browsers - *supports version 4, version 6, [custom keywords](https://github.com/epoberezkin/ajv-keywords) and [$data reference](https://github.com/json-schema-org/json-schema-spec/issues/51)* (MIT)
- djv for Node.js and browsers - *supports version 4* (MIT)
- jsonschema for Node.js - *supports version 4* (MIT)
- is-my-json-valid - *supports version 4* (MIT)