diff --git a/pyproject.toml b/pyproject.toml
index 6b86858..2f52869 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -57,7 +57,7 @@ dev = [
     "pytest-cov>=7.0.0",
     "pytest-mock>=3.15.1",
     # Documentation
-    "sphinx==8.1.3",
+    "sphinx==8.2.3",
     "sphinx-rtd-theme>=3.0.0",
     "sphinx_immaterial>=0.13.8",
     "sphinx-autodoc-typehints==3.0.1",
diff --git a/requirements-dev.txt b/requirements-dev.txt
index ba124ff..a08a256 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -99,7 +99,7 @@ ruff==0.15.2
     # via pyUSPTO (pyproject.toml)
 snowballstemmer==3.0.1
     # via sphinx
-sphinx==8.1.3
+sphinx==8.2.3
     # via
     #   myst-parser
     #   pyUSPTO (pyproject.toml)