diff --git a/textproc/py-sphinxcontrib-log-cabinet/Makefile b/textproc/py-sphinxcontrib-log-cabinet/Makefile
index 6cb520466186..d73f263fb5dc 100644
--- a/textproc/py-sphinxcontrib-log-cabinet/Makefile
+++ b/textproc/py-sphinxcontrib-log-cabinet/Makefile
@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.2 2022/01/04 20:55:07 wiz Exp $
+# $NetBSD: Makefile,v 1.3 2022/07/11 07:22:04 wiz Exp $
 
 DISTNAME=	sphinxcontrib-log-cabinet-1.0.1
 PKGNAME=	${PYPKGPREFIX}-${DISTNAME}
@@ -13,6 +13,8 @@ LICENSE=	modified-bsd
 
 DEPENDS+=	${PYPKGPREFIX}-sphinx-[0-9]*:../../textproc/py-sphinx
 
+PYTHON_VERSIONS_INCOMPATIBLE=	27
+
 USE_LANGUAGES=	# none
 
 .include "../../lang/python/egg.mk"