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 # Wikibase DataModel Serialization release notes
 
+## 2.9.1 (2018-12-14)
+
+* Apply ID prefix mapping in `SnakDeserializer`, like `EntityIdValueParser` does.
+
 ## 2.9.0 (2018-11-06)
 
 * Added compatibility with Wikibase DataModel 9.x