diff --git a/spec/services/activitypub/fetch_remote_key_service_spec.rb b/spec/services/activitypub/fetch_remote_key_service_spec.rb
new file mode 100644
index 000000000..3186c4270
--- /dev/null
+++ b/spec/services/activitypub/fetch_remote_key_service_spec.rb
@@ -0,0 +1,83 @@
+require 'rails_helper'
+
+RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
+  subject { ActivityPub::FetchRemoteKeyService.new }
+
+  let(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
+
+  let(:public_key_pem) do
+    "-----BEGIN PUBLIC KEY-----\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAu3L4vnpNLzVH31MeWI39\n4F0wKeJFsLDAsNXGeOu0QF2x+h1zLWZw/agqD2R3JPU9/kaDJGPIV2Sn5zLyUA9S\n6swCCMOtn7BBR9g9sucgXJmUFB0tACH2QSgHywMAybGfmSb3LsEMNKsGJ9VsvYoh\n8lDET6X4Pyw+ZJU0/OLo/41q9w+OrGtlsTm/PuPIeXnxa6BLqnDaxC+4IcjG/FiP\nahNCTINl/1F/TgSSDZ4Taf4U9XFEIFw8wmgploELozzIzKq+t8nhQYkgAkt64euW\npva3qL5KD1mTIZQEP+LZvh3s2WHrLi3fhbdRuwQ2c0KkJA2oSTFPDpqqbPGZ3Qvu\nHQIDAQAB\n-----END PUBLIC KEY-----\n"
+  end
+
+  let(:public_key_id) { 'https://example.com/alice#main-key' }
+
+  let(:key_json) do
+    {
+      id: public_key_id,
+      owner: 'https://example.com/alice',
+      publicKeyPem: public_key_pem,
+    }
+  end
+
+  let(:actor_public_key) { key_json }
+
+  let(:actor) do
+    {
+      '@context': [
+        'https://www.w3.org/ns/activitystreams',
+        'https://w3id.org/security/v1',
+      ],
+      id: 'https://example.com/alice',
+      type: 'Person',
+      preferredUsername: 'alice',
+      name: 'Alice',
+      summary: 'Foo bar',
+      inbox: 'http://example.com/alice/inbox',
+      publicKey: actor_public_key,
+    }
+  end
+
+  before do
+    stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+    stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
+  end
+
+  describe '#call' do
+    let(:account) { subject.call(public_key_id, id: false) }
+
+    context 'when the key is a sub-object from the actor' do
+      before do
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(actor))
+      end
+
+      it 'returns the expected account' do
+        expect(account.uri).to eq 'https://example.com/alice'
+      end
+    end
+
+    context 'when the key is a separate document' do
+      let(:public_key_id) { 'https://example.com/alice-public-key.json' }
+
+      before do
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+      end
+
+      it 'returns the expected account' do
+        expect(account.uri).to eq 'https://example.com/alice'
+      end
+    end
+
+    context 'when the key and owner do not match' do
+      let(:public_key_id) { 'https://example.com/fake-public-key.json' }
+      let(:actor_public_key) { 'https://example.com/alice-public-key.json' }
+
+      before do
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+      end
+
+      it 'returns the nil' do
+        expect(account).to be_nil
+      end
+    end
+  end
+end