diff --git a/spec/classes/puppet_agent_osfamily_darwin_spec.rb b/spec/classes/puppet_agent_osfamily_darwin_spec.rb
index bd0880e0..80f77cdd 100644
--- a/spec/classes/puppet_agent_osfamily_darwin_spec.rb
+++ b/spec/classes/puppet_agent_osfamily_darwin_spec.rb
@@ -42,7 +42,7 @@
     let(:params) { { package_version: package_version } }
 
     context 'when running a supported macOS' do
-      ['osx-10.15-x86_64', 'osx-11-x86_64', 'osx-12-x86_64'].each do |tag|
+      ['osx-11-x86_64', 'osx-12-x86_64'].each do |tag|
         context "on #{tag} with no aio_version" do
           let(:osmajor) { tag.split('-')[1] }
 
diff --git a/tasks/install_shell.sh b/tasks/install_shell.sh
index bf3ca140..1a9a7f93 100644
--- a/tasks/install_shell.sh
+++ b/tasks/install_shell.sh
@@ -227,17 +227,10 @@ if [ -f "$PT__installdir/facts/tasks/bash.sh" ]; then
 
     major_version=`echo $platform_version | cut -d. -f1,2`
 
-    # Excepting macOS 10.x, the major version is the first number only
-    if ! echo "${major_version}" | grep -q '^10\.'; then
-        major_version=$(echo "${major_version}" | cut -d '.' -f 1);
-    fi
+    # The major version is the first number only
+    major_version=$(echo "${major_version}" | cut -d '.' -f 1);
 
     case $major_version in
-      "10.11") platform_version="10.11";;
-      "10.12") platform_version="10.12";;
-      "10.13") platform_version="10.13";;
-      "10.14") platform_version="10.14";;
-      "10.15") platform_version="10.15";;
       "11")    platform_version="11";;
       "12")    platform_version="12";;
       *) echo "No builds for platform: $major_version"