diff --git a/requirements.txt b/requirements.txt
index 66c4316..2fb5bb8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,11 +1,3 @@
-Sphinx==3.0.4
+sphinx==3.0.4
 http://github.com/SymbiFlow/sphinx_materialdesign_theme/archive/master.zip#sphinx_symbiflow_theme
 http://github.com/SymbiFlow/sphinx-verilog-domain/archive/master.zip#sphinx-verilog-domain
-sphinx-markdown-tables==0.0.12
-breathe==4.18.1
-https://github.com/hdl/pyHDLParser/archive/master.zip#hdlparse
-https://github.com/hdl/symbolator/archive/master.zip#symbolator
-sphinxcontrib-images==0.9.2
-recommonmark==0.6.0
-sphinxcontrib-bibtex==0.4.2
-sphinxcontrib-domaintools==0.3