diff --git a/bionty_base/entities/_experimentalfactor.py b/bionty_base/entities/_experimentalfactor.py
index 5b9ba613..ad7e101a 100644
--- a/bionty_base/entities/_experimentalfactor.py
+++ b/bionty_base/entities/_experimentalfactor.py
@@ -1,4 +1,3 @@
-from functools import cached_property
 from typing import Dict, Literal, Optional
 
 import pandas as pd
diff --git a/bionty_base/sources.yaml b/bionty_base/sources.yaml
index 30232ced..a46ab02d 100644
--- a/bionty_base/sources.yaml
+++ b/bionty_base/sources.yaml
@@ -194,6 +194,9 @@ Disease:
 ExperimentalFactor:
   efo:
     all:
+      3.63.0:
+        url: http://www.ebi.ac.uk/efo/releases/v3.63.0/efo.owl
+        md5: 603e6f6981d53d501c5921aa3940b095
       3.57.0:
         url: http://www.ebi.ac.uk/efo/releases/v3.57.0/efo.owl
         md5: 2ecafc69b3aba7bdb31ad99438505c05
diff --git a/docs/changelog.md b/docs/changelog.md
index 24f984c8..3b2de8d6 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -3,6 +3,7 @@
 <!-- prettier-ignore -->
 Name | PR | Developer | Date | Version
 --- | --- | --- | --- | ---
+ ✨ New ontology: ExperimentalFactor-efo-3.63 | [577](https://github.com/laminlabs/bionty-base/pull/577) | [Zethson](https://github.com/Zethson) | 2024-05-15 |
 ✨ New ontology: CellType-cl-2024-02-13 | [576](https://github.com/laminlabs/bionty-base/pull/576) | [Zethson](https://github.com/Zethson) | 2024-05-15 |
 :sparkles: New Ontology: Tissue-uberon-2024-02-20 | [575](https://github.com/laminlabs/bionty-base/pull/575) | [Zethson](https://github.com/Zethson) | 2024-05-15 |
 ✨ New ontology: Organism-ensembl-release-111 and Organism-ensembl-release-112 | [574](https://github.com/laminlabs/bionty-base/pull/574) | [sunnyosun](https://github.com/sunnyosun) | 2024-05-15 |