diff --git a/requirements.txt b/requirements.txt
index 09db445..22aba1d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 rdflib<6.0.0
-pydantic>=1.8.1
+pydantic~=1.8.1
 email-validator
 jsonschema2md
 black
diff --git a/setup.py b/setup.py
index a9c08cc..a765e69 100644
--- a/setup.py
+++ b/setup.py
@@ -9,7 +9,7 @@
                            exclude=("tests",)),
     install_requires=[
         'rdflib<6.0.0',
-        'pydantic>=1.8.1',
+        'pydantic~=1.8.1',
         'email-validator'
     ],
     url='https://github.com/hydroshare/hsmodels',