diff --git a/requirements/docs.txt b/requirements/docs.txt
index 9795a07c7..d8f2cb82b 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -2,7 +2,7 @@
 # core dependencies
 sphinx>=4.2.0, <8.0.0
 sphinx-autodoc-typehints>=1.12.0, <1.21  # limited due to https://github.com/tox-dev/sphinx-autodoc-typehints/issues/260
-sphinx-rtd-theme>=1.0.0, <2.0.0
+sphinx-rtd-theme>=1.0.0, <4.0.0
 sphinxcontrib-apidoc>=0.3.0, <0.5.0
 sphinxcontrib-bibtex>=2.1.0, <3.0.0
 myst-parser>=1.0, <3.0