diff --git a/lib/code_teams/testing.rb b/lib/code_teams/testing.rb
index f28886d..f3ecc57 100644
--- a/lib/code_teams/testing.rb
+++ b/lib/code_teams/testing.rb
@@ -51,6 +51,11 @@ def self.create_code_team(attributes)
       )
 
       code_teams << code_team
+      # Plugin's registry is keyed by team name, and the hook above only busts it after an
+      # example that built a fake team. An example reading only real teams therefore leaves
+      # real-team plugin instances behind, and a fake team sharing a real team's name would
+      # inherit that cached data. Drop the registry so the fake registers first.
+      Plugin.bust_caches!
       code_team
     end
 
diff --git a/spec/lib/code_teams/testing_spec.rb b/spec/lib/code_teams/testing_spec.rb
index 53b6e0e..4e8611d 100644
--- a/spec/lib/code_teams/testing_spec.rb
+++ b/spec/lib/code_teams/testing_spec.rb
@@ -11,5 +11,23 @@
       expect(CodeTeams.find('Temp Team')).to eq(team)
       expect(team.raw_hash.dig('extra_data', 'foo', 'bar')).to eq(1)
     end
+
+    it 'does not let a fake team inherit a real same-named team\'s cached plugin data' do
+      test_plugin_class = Class.new(CodeTeams::Plugin) do
+        def test_plugin
+          Data.define(:source).new(@team.raw_hash['extra_data']['source'])
+        end
+      end
+      stub_const('TestPlugin', test_plugin_class)
+      CodeTeams.bust_caches!
+      write_team_yml(extra_data: { 'source' => 'real' })
+
+      # Reading the real team caches its plugin instance under the name 'My Team'.
+      expect(CodeTeams.find('My Team').test_plugin.source).to eq('real')
+
+      fake = described_class.create_code_team({ name: 'My Team', extra_data: { 'source' => 'fake' } })
+
+      expect(fake.test_plugin.source).to eq('fake')
+    end
   end
 end