diff --git a/lib/licensee/project_files/license_file.rb b/lib/licensee/project_files/license_file.rb
index 05b258f..0039bdc 100644
--- a/lib/licensee/project_files/license_file.rb
+++ b/lib/licensee/project_files/license_file.rb
@@ -7,8 +7,8 @@ module Licensee
       PREFERRED_EXT = %w[md markdown txt].freeze
       PREFERRED_EXT_REGEX = /\.#{Regexp.union(PREFERRED_EXT)}\z/
 
-      # Regex to match any extension except .spdx
-      NONSPDX_EXT_REGEX = %r{\.(?!spdx)[^./]+\z}
+      # Regex to match any extension except .spdx or .header
+      OTHER_EXT_REGEX = %r{\.(?!spdx|header)[^./]+\z}i
 
       # Regex to match, LICENSE, LICENCE, unlicense, etc.
       LICENSE_REGEX = /(un)?licen[sc]e/i
@@ -28,17 +28,17 @@ module Licensee
         /\A#{LICENSE_REGEX}#{PREFERRED_EXT_REGEX}\z/ => 0.95,  # LICENSE.md
         /\A#{COPYING_REGEX}\z/                       => 0.90,  # COPYING
         /\A#{COPYING_REGEX}#{PREFERRED_EXT_REGEX}\z/ => 0.85,  # COPYING.md
-        /\A#{LICENSE_REGEX}#{NONSPDX_EXT_REGEX}\z/   => 0.80,  # LICENSE.textile
-        /\A#{COPYING_REGEX}#{NONSPDX_EXT_REGEX}\z/   => 0.75,  # COPYING.textile
+        /\A#{LICENSE_REGEX}#{OTHER_EXT_REGEX}\z/     => 0.80,  # LICENSE.textile
+        /\A#{COPYING_REGEX}#{OTHER_EXT_REGEX}\z/     => 0.75,  # COPYING.textile
         /\A#{LICENSE_REGEX}[-_]/                     => 0.70,  # LICENSE-MIT
         /\A#{COPYING_REGEX}[-_]/                     => 0.65,  # COPYING-MIT
         /[-_]#{LICENSE_REGEX}/                       => 0.60,  # MIT-LICENSE-MIT
         /[-_]#{COPYING_REGEX}/                       => 0.55,  # MIT-COPYING
         /\A#{OFL_REGEX}#{PREFERRED_EXT_REGEX}/       => 0.50,  # OFL.md
-        /\A#{OFL_REGEX}#{NONSPDX_EXT_REGEX}/         => 0.45,  # OFL.textile
+        /\A#{OFL_REGEX}#{OTHER_EXT_REGEX}/           => 0.45,  # OFL.textile
         /\A#{OFL_REGEX}\z/                           => 0.40,  # OFL
         /\A#{PATENTS_REGEX}\z/                       => 0.35,  # PATENTS
-        /\A#{PATENTS_REGEX}#{NONSPDX_EXT_REGEX}\z/   => 0.30,  # PATENTS.txt
+        /\A#{PATENTS_REGEX}#{OTHER_EXT_REGEX}\z/     => 0.30,  # PATENTS.txt
         //                                           => 0.00   # Catch all
       }.freeze
 
diff --git a/lib/licensee/project_files/project_file.rb b/lib/licensee/project_files/project_file.rb
index 0a1e315..e1c8908 100644
--- a/lib/licensee/project_files/project_file.rb
+++ b/lib/licensee/project_files/project_file.rb
@@ -66,7 +66,7 @@ module Licensee
       def copyright?
         return false unless is_a?(LicenseFile)
         return false unless matcher.is_a?(Matchers::Copyright)
-        filename =~ /\Acopyright(?:#{LicenseFile::NONSPDX_EXT_REGEX})?\z/i
+        filename =~ /\Acopyright(?:#{LicenseFile::OTHER_EXT_REGEX})?\z/i
       end
     end
   end
diff --git a/spec/licensee/project_files/license_file_spec.rb b/spec/licensee/project_files/license_file_spec.rb
index 808a0f7..1c7239d 100644
--- a/spec/licensee/project_files/license_file_spec.rb
+++ b/spec/licensee/project_files/license_file_spec.rb
@@ -109,11 +109,11 @@ RSpec.describe Licensee::ProjectFiles::LicenseFile do
 
     context 'any extension regex' do
       it 'matches .foo' do
-        expect(described_class::NONSPDX_EXT_REGEX).to match('.foo')
+        expect(described_class::OTHER_EXT_REGEX).to match('.foo')
       end
 
       it 'does not match .md/foo' do
-        expect(described_class::NONSPDX_EXT_REGEX).to_not match('.md/foo')
+        expect(described_class::OTHER_EXT_REGEX).to_not match('.md/foo')
       end
     end