diff --git a/manifests/params.pp b/manifests/params.pp
index b0ad60c71a..479ac12235 100644
--- a/manifests/params.pp
+++ b/manifests/params.pp
@@ -9,6 +9,7 @@
   $provider       = '/usr/bin/apt-get'
   $sources_list   = "${root}/sources.list"
   $sources_list_d = "${root}/sources.list.d"
+  $trusted_gpg_d  = "${root}/trusted.gpg.d"
   $conf_d         = "${root}/apt.conf.d"
   $preferences    = "${root}/preferences"
   $preferences_d  = "${root}/preferences.d"
diff --git a/manifests/ppa.pp b/manifests/ppa.pp
index a67e1a1945..740d59643c 100644
--- a/manifests/ppa.pp
+++ b/manifests/ppa.pp
@@ -16,14 +16,25 @@
 
   if versioncmp($facts['lsbdistrelease'], '15.10') >= 0 {
     $distid = downcase($facts['lsbdistid'])
-    $filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1-${distid}-\\2-${release}")
+    $dash_filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1-${distid}-\\2")
+    $underscore_filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1_${distid}_\\2")
   } else {
-    $filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1-\\2-${release}")
+    $dash_filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1-\\2")
+    $underscore_filename = regsubst($name, '^ppa:([^/]+)/(.+)$', "\\1_\\2")
   }
 
-  $filename_no_slashes      = regsubst($filename, '/', '-', 'G')
-  $filename_no_specialchars = regsubst($filename_no_slashes, '[\.\+]', '_', 'G')
-  $sources_list_d_filename  = "${filename_no_specialchars}.list"
+  $dash_filename_no_slashes      = regsubst($dash_filename, '/', '-', 'G')
+  $dash_filename_no_specialchars = regsubst($dash_filename_no_slashes, '[\.\+]', '_', 'G')
+  $underscore_filename_no_slashes      = regsubst($underscore_filename, '/', '-', 'G')
+  $underscore_filename_no_specialchars = regsubst($underscore_filename_no_slashes, '[\.\+]', '_', 'G')
+
+  $sources_list_d_filename  = "${dash_filename_no_specialchars}-${release}.list"
+
+  if versioncmp($facts['lsbdistrelease'], '15.10') >= 0 {
+    $trusted_gpg_d_filename = "${underscore_filename_no_specialchars}.gpg"
+  } else {
+    $trusted_gpg_d_filename = "${dash_filename_no_specialchars}.gpg"
+  }
 
   if $ensure == 'present' {
     if $package_manage {
@@ -47,7 +58,7 @@
     exec { "add-apt-repository-${name}":
       environment => $_proxy_env,
       command     => "/usr/bin/add-apt-repository ${options} ${name}",
-      unless      => "/usr/bin/test -f ${::apt::sources_list_d}/${sources_list_d_filename}",
+      unless      => "/usr/bin/test -f ${::apt::sources_list_d}/${sources_list_d_filename} && /usr/bin/test -f ${::apt::trusted_gpg_d}/${trusted_gpg_d_filename}",
       user        => 'root',
       logoutput   => 'on_failure',
       notify      => Class['apt::update'],
diff --git a/spec/defines/ppa_spec.rb b/spec/defines/ppa_spec.rb
index 497822109d..4c4dddb171 100644
--- a/spec/defines/ppa_spec.rb
+++ b/spec/defines/ppa_spec.rb
@@ -23,7 +23,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:needs/such.substitution/wow+type').that_notifies('Class[Apt::Update]').with(environment: [],
                                                                                                                                       command: '/usr/bin/add-apt-repository -y ppa:needs/such.substitution/wow+type', # rubocop:disable Metrics/LineLength
-                                                                                                                                      unless: '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow_type-trusty.list', # rubocop:disable Metrics/LineLength
+                                                                                                                                      unless: '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow_type-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/needs-such_substitution-wow_type.gpg', # rubocop:disable Metrics/LineLength
                                                                                                                                       user: 'root',
                                                                                                                                       logoutput: 'on_failure')
     }
@@ -47,7 +47,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:user/foo').that_notifies('Class[Apt::Update]').with(environment: [],
                                                                                                               command: '/usr/bin/add-apt-repository -y ppa:user/foo',
-                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-ubuntu-foo-wily.list',
+                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-ubuntu-foo-wily.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/user_ubuntu_foo.gpg', # rubocop:disable Metrics/LineLength
                                                                                                               user: 'root',
                                                                                                               logoutput: 'on_failure')
     }
@@ -81,7 +81,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:needs/such.substitution/wow').that_notifies('Class[Apt::Update]').with('environment' => [],
                                                                                                                                  'command'     => '/usr/bin/add-apt-repository -y ppa:needs/such.substitution/wow', # rubocop:disable Metrics/LineLength
-                                                                                                                                 'unless'      => '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow-trusty.list', # rubocop:disable Metrics/LineLength
+                                                                                                                                 'unless'      => '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/needs-such_substitution-wow.gpg', # rubocop:disable Metrics/LineLength
                                                                                                                                  'user'        => 'root',
                                                                                                                                  'logoutput'   => 'on_failure')
     }
@@ -118,7 +118,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:needs/such.substitution/wow').that_notifies('Class[Apt::Update]').with('environment' => [],
                                                                                                                                  'command'     => '/usr/bin/add-apt-repository -y ppa:needs/such.substitution/wow', # rubocop:disable Metrics/LineLength
-                                                                                                                                 'unless'      => '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow-trusty.list', # rubocop:disable Metrics/LineLength
+                                                                                                                                 'unless'      => '/usr/bin/test -f /etc/apt/sources.list.d/needs-such_substitution-wow-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/needs-such_substitution-wow.gpg', # rubocop:disable Metrics/LineLength
                                                                                                                                  'user'        => 'root',
                                                                                                                                  'logoutput'   => 'on_failure')
     }
@@ -159,7 +159,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:user/foo').that_notifies('Class[Apt::Update]').with(environment: [],
                                                                                                               command: '/usr/bin/add-apt-repository  ppa:user/foo',
-                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list',
+                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/user-foo.gpg', # rubocop:disable Metrics/LineLength
                                                                                                               user: 'root',
                                                                                                               logoutput: 'on_failure')
     }
@@ -194,7 +194,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:user/foo').that_notifies('Class[Apt::Update]').with(environment: ['http_proxy=http://localhost:8080'],
                                                                                                               command: '/usr/bin/add-apt-repository  ppa:user/foo',
-                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list',
+                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/user-foo.gpg', # rubocop:disable Metrics/LineLength
                                                                                                               user: 'root',
                                                                                                               logoutput: 'on_failure')
     }
@@ -229,7 +229,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:user/foo').that_notifies('Class[Apt::Update]').with(environment: ['http_proxy=http://localhost:8180'],
                                                                                                               command: '/usr/bin/add-apt-repository  ppa:user/foo',
-                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list',
+                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/user-foo.gpg', # rubocop:disable Metrics/LineLength
                                                                                                               user: 'root',
                                                                                                               logoutput: 'on_failure')
     }
@@ -264,7 +264,7 @@
     it {
       is_expected.to contain_exec('add-apt-repository-ppa:user/foo').that_notifies('Class[Apt::Update]').with(environment: ['http_proxy=http://localhost:8180', 'https_proxy=https://localhost:8180'],
                                                                                                               command: '/usr/bin/add-apt-repository  ppa:user/foo',
-                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list',
+                                                                                                              unless: '/usr/bin/test -f /etc/apt/sources.list.d/user-foo-trusty.list && /usr/bin/test -f /etc/apt/trusted.gpg.d/user-foo.gpg', # rubocop:disable Metrics/LineLength
                                                                                                               user: 'root',
                                                                                                               logoutput: 'on_failure')
     }