The Apache OpenNLP team is pleased to announce the release of Apache OpenNLP 2.5.11.
The Apache OpenNLP library is a machine learning based toolkit for the processing of natural language text.
It supports the most common NLP tasks, such as tokenization, sentence segmentation, part-of-speech tagging, named entity extraction, chunking, parsing, and coreference resolution.
Apache OpenNLP 2.5.11 binary and source distributions are available for download from our download page.
The OpenNLP library is distributed by Maven Central as well. See the Maven dependency page for more details.
This is a maintenance release on the 2.x line. It refreshes several dependencies.
Class instantiation in StreamFactory / StringInterners is now allowlist-based (OPENNLP-1890)
Deserialization in BaseModel has been hardened (OPENNLP-1891)
DocBook DTDs are now resolved from a local catalog instead of a remote URL (OPENNLP-1854)
Move to Apache Parent 39 (OPENNLP-1855)
Update JUnit to 6.1.2 (OPENNLP-1856)
Update ONNX runtime to 1.27.0 (OPENNLP-1873)
Update Log4j2 to 2.26.1 (OPENNLP-1874)
For further details, check the full list of changes via the project’s issue tracker.
--The Apache OpenNLP Team
24 July 2026