diff --git a/data/migrations/Version20180913205455.php b/data/migrations/Version20180913205455.php
index 8afa316b..c2bc2070 100644
--- a/data/migrations/Version20180913205455.php
+++ b/data/migrations/Version20180913205455.php
@@ -58,7 +58,7 @@ final class Version20180913205455 extends AbstractMigration
         }
 
         try {
-            return (string) IpAddress::fromString($addr)->getObfuscatedCopy();
+            return (string) IpAddress::fromString($addr)->getAnonymizedCopy();
         } catch (InvalidArgumentException $e) {
             return null;
         }
diff --git a/module/Rest/src/Action/ShortUrl/CreateShortUrlAction.php b/module/Rest/src/Action/ShortUrl/CreateShortUrlAction.php
index 28941579..b3db6460 100644
--- a/module/Rest/src/Action/ShortUrl/CreateShortUrlAction.php
+++ b/module/Rest/src/Action/ShortUrl/CreateShortUrlAction.php
@@ -28,7 +28,7 @@ class CreateShortUrlAction extends AbstractCreateShortUrlAction
             ]);
         }
 
-        $payload[ShortUrlMetaInputFilter::API_KEY] = AuthenticationMiddleware::apiKeyFromRequest($request);
+        $payload[ShortUrlMetaInputFilter::API_KEY] = AuthenticationMiddleware::apiKeyFromRequest($request)->toString();
         $meta = ShortUrlMeta::fromRawData($payload);
 
         return new CreateShortUrlData($payload['longUrl'], (array) ($payload['tags'] ?? []), $meta);
diff --git a/module/Rest/src/Action/ShortUrl/SingleStepCreateShortUrlAction.php b/module/Rest/src/Action/ShortUrl/SingleStepCreateShortUrlAction.php
index fe8c44aa..996e59a6 100644
--- a/module/Rest/src/Action/ShortUrl/SingleStepCreateShortUrlAction.php
+++ b/module/Rest/src/Action/ShortUrl/SingleStepCreateShortUrlAction.php
@@ -34,10 +34,10 @@ class SingleStepCreateShortUrlAction extends AbstractCreateShortUrlAction
     protected function buildShortUrlData(Request $request): CreateShortUrlData
     {
         $query = $request->getQueryParams();
-        $apiKey = $query['apiKey'] ?? '';
         $longUrl = $query['longUrl'] ?? null;
 
-        if (! $this->apiKeyService->check($apiKey)) {
+        $apiKeyResult = $this->apiKeyService->check($query['apiKey'] ?? '');
+        if (! $apiKeyResult->isValid()) {
             throw ValidationException::fromArray([
                 'apiKey' => 'No API key was provided or it is not valid',
             ]);
@@ -50,7 +50,7 @@ class SingleStepCreateShortUrlAction extends AbstractCreateShortUrlAction
         }
 
         return new CreateShortUrlData($longUrl, [], ShortUrlMeta::fromRawData([
-            ShortUrlMetaInputFilter::API_KEY => $apiKey,
+            ShortUrlMetaInputFilter::API_KEY => $apiKeyResult->apiKey()->toString(),
         ]));
     }
 }
diff --git a/module/Rest/src/Entity/ApiKey.php b/module/Rest/src/Entity/ApiKey.php
index 1d372c9c..a800d530 100644
--- a/module/Rest/src/Entity/ApiKey.php
+++ b/module/Rest/src/Entity/ApiKey.php
@@ -54,4 +54,9 @@ class ApiKey extends AbstractEntity
     {
         return $this->key;
     }
+
+    public function toString(): string
+    {
+        return $this->key;
+    }
 }
diff --git a/module/Rest/src/Middleware/AuthenticationMiddleware.php b/module/Rest/src/Middleware/AuthenticationMiddleware.php
index add9f513..1eff50d2 100644
--- a/module/Rest/src/Middleware/AuthenticationMiddleware.php
+++ b/module/Rest/src/Middleware/AuthenticationMiddleware.php
@@ -11,6 +11,7 @@ use Psr\Http\Message\ResponseInterface as Response;
 use Psr\Http\Message\ServerRequestInterface as Request;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
 use Shlinkio\Shlink\Rest\Exception\MissingAuthenticationException;
 use Shlinkio\Shlink\Rest\Exception\VerifyAuthenticationException;
 use Shlinkio\Shlink\Rest\Service\ApiKeyServiceInterface;
@@ -43,20 +44,21 @@ class AuthenticationMiddleware implements MiddlewareInterface, StatusCodeInterfa
             return $handler->handle($request);
         }
 
-        $apiKey = self::apiKeyFromRequest($request);
+        $apiKey = $request->getHeaderLine(self::API_KEY_HEADER);
         if (empty($apiKey)) {
             throw MissingAuthenticationException::fromExpectedTypes([self::API_KEY_HEADER]);
         }
 
-        if (! $this->apiKeyService->check($apiKey)) {
+        $result = $this->apiKeyService->check($apiKey);
+        if (! $result->isValid()) {
             throw VerifyAuthenticationException::forInvalidApiKey();
         }
 
-        return $handler->handle($request);
+        return $handler->handle($request->withAttribute(ApiKey::class, $result->apiKey()));
     }
 
-    public static function apiKeyFromRequest(Request $request): string
+    public static function apiKeyFromRequest(Request $request): ApiKey
     {
-        return $request->getHeaderLine(self::API_KEY_HEADER);
+        return $request->getAttribute(ApiKey::class);
     }
 }
diff --git a/module/Rest/src/Service/ApiKeyCheckResult.php b/module/Rest/src/Service/ApiKeyCheckResult.php
new file mode 100644
index 00000000..8ec3f65e
--- /dev/null
+++ b/module/Rest/src/Service/ApiKeyCheckResult.php
@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Shlinkio\Shlink\Rest\Service;
+
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
+
+final class ApiKeyCheckResult
+{
+    private ?ApiKey $apiKey;
+
+    public function __construct(?ApiKey $apiKey = null)
+    {
+        $this->apiKey = $apiKey;
+    }
+
+    public function isValid(): bool
+    {
+        return $this->apiKey !== null && $this->apiKey->isValid();
+    }
+
+    public function apiKey(): ?ApiKey
+    {
+        return $this->apiKey;
+    }
+}
diff --git a/module/Rest/src/Service/ApiKeyService.php b/module/Rest/src/Service/ApiKeyService.php
index baa545c0..6fb61be9 100644
--- a/module/Rest/src/Service/ApiKeyService.php
+++ b/module/Rest/src/Service/ApiKeyService.php
@@ -29,11 +29,11 @@ class ApiKeyService implements ApiKeyServiceInterface
         return $key;
     }
 
-    public function check(string $key): bool
+    public function check(string $key): ApiKeyCheckResult
     {
         /** @var ApiKey|null $apiKey */
         $apiKey = $this->getByKey($key);
-        return $apiKey !== null && $apiKey->isValid();
+        return new ApiKeyCheckResult($apiKey);
     }
 
     /**
@@ -63,7 +63,7 @@ class ApiKeyService implements ApiKeyServiceInterface
         return $apiKeys;
     }
 
-    public function getByKey(string $key): ?ApiKey
+    private function getByKey(string $key): ?ApiKey
     {
         /** @var ApiKey|null $apiKey */
         $apiKey = $this->em->getRepository(ApiKey::class)->findOneBy([
diff --git a/module/Rest/src/Service/ApiKeyServiceInterface.php b/module/Rest/src/Service/ApiKeyServiceInterface.php
index a08d8c60..e8c6d0ea 100644
--- a/module/Rest/src/Service/ApiKeyServiceInterface.php
+++ b/module/Rest/src/Service/ApiKeyServiceInterface.php
@@ -12,7 +12,7 @@ interface ApiKeyServiceInterface
 {
     public function create(?Chronos $expirationDate = null): ApiKey;
 
-    public function check(string $key): bool;
+    public function check(string $key): ApiKeyCheckResult;
 
     /**
      * @throws InvalidArgumentException
@@ -23,6 +23,4 @@ interface ApiKeyServiceInterface
      * @return ApiKey[]
      */
     public function listKeys(bool $enabledOnly = false): array;
-
-    public function getByKey(string $key): ?ApiKey;
 }
diff --git a/module/Rest/test/Action/ShortUrl/CreateShortUrlActionTest.php b/module/Rest/test/Action/ShortUrl/CreateShortUrlActionTest.php
index 91e6014c..082b1783 100644
--- a/module/Rest/test/Action/ShortUrl/CreateShortUrlActionTest.php
+++ b/module/Rest/test/Action/ShortUrl/CreateShortUrlActionTest.php
@@ -16,6 +16,7 @@ use Shlinkio\Shlink\Core\Exception\ValidationException;
 use Shlinkio\Shlink\Core\Model\ShortUrlMeta;
 use Shlinkio\Shlink\Core\Service\UrlShortener;
 use Shlinkio\Shlink\Rest\Action\ShortUrl\CreateShortUrlAction;
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
 
 use function strpos;
 
@@ -48,19 +49,19 @@ class CreateShortUrlActionTest extends TestCase
      * @test
      * @dataProvider provideRequestBodies
      */
-    public function properShortcodeConversionReturnsData(array $body, ShortUrlMeta $expectedMeta, ?string $apiKey): void
+    public function properShortcodeConversionReturnsData(array $body, array $expectedMeta): void
     {
+        $apiKey = new ApiKey();
         $shortUrl = new ShortUrl('');
+        $expectedMeta['apiKey'] = $apiKey->toString();
+
         $shorten = $this->urlShortener->shorten(
             Argument::type('string'),
             Argument::type('array'),
-            $expectedMeta,
+            ShortUrlMeta::fromRawData($expectedMeta),
         )->willReturn($shortUrl);
 
-        $request = ServerRequestFactory::fromGlobals()->withParsedBody($body);
-        if ($apiKey !== null) {
-            $request = $request->withHeader('X-Api-Key', $apiKey);
-        }
+        $request = ServerRequestFactory::fromGlobals()->withParsedBody($body)->withAttribute(ApiKey::class, $apiKey);
 
         $response = $this->action->handle($request);
 
@@ -81,14 +82,8 @@ class CreateShortUrlActionTest extends TestCase
             'domain' => 'my-domain.com',
         ];
 
-        yield 'no data' => [['longUrl' => 'http://www.domain.com/foo/bar'], ShortUrlMeta::createEmpty(), null];
-        yield 'all data' => [$fullMeta, ShortUrlMeta::fromRawData($fullMeta), null];
-        yield 'all data and API key' => (static function (array $meta): array {
-            $apiKey = 'abc123';
-            $meta['apiKey'] = $apiKey;
-
-            return [$meta, ShortUrlMeta::fromRawData($meta), $apiKey];
-        })($fullMeta);
+        yield 'no data' => [['longUrl' => 'http://www.domain.com/foo/bar'], []];
+        yield 'all data' => [$fullMeta, $fullMeta];
     }
 
     /**
@@ -103,7 +98,7 @@ class CreateShortUrlActionTest extends TestCase
         $request = (new ServerRequest())->withParsedBody([
             'longUrl' => 'http://www.domain.com/foo/bar',
             'domain' => $domain,
-        ]);
+        ])->withAttribute(ApiKey::class, new ApiKey());
 
         $this->expectException(ValidationException::class);
         $urlToShortCode->shouldNotBeCalled();
diff --git a/module/Rest/test/Action/ShortUrl/SingleStepCreateShortUrlActionTest.php b/module/Rest/test/Action/ShortUrl/SingleStepCreateShortUrlActionTest.php
index 62005c8d..eb1d6cd2 100644
--- a/module/Rest/test/Action/ShortUrl/SingleStepCreateShortUrlActionTest.php
+++ b/module/Rest/test/Action/ShortUrl/SingleStepCreateShortUrlActionTest.php
@@ -15,6 +15,8 @@ use Shlinkio\Shlink\Core\Exception\ValidationException;
 use Shlinkio\Shlink\Core\Model\ShortUrlMeta;
 use Shlinkio\Shlink\Core\Service\UrlShortenerInterface;
 use Shlinkio\Shlink\Rest\Action\ShortUrl\SingleStepCreateShortUrlAction;
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
+use Shlinkio\Shlink\Rest\Service\ApiKeyCheckResult;
 use Shlinkio\Shlink\Rest\Service\ApiKeyServiceInterface;
 
 class SingleStepCreateShortUrlActionTest extends TestCase
@@ -44,7 +46,7 @@ class SingleStepCreateShortUrlActionTest extends TestCase
     public function errorResponseIsReturnedIfInvalidApiKeyIsProvided(): void
     {
         $request = (new ServerRequest())->withQueryParams(['apiKey' => 'abc123']);
-        $findApiKey = $this->apiKeyService->check('abc123')->willReturn(false);
+        $findApiKey = $this->apiKeyService->check('abc123')->willReturn(new ApiKeyCheckResult());
 
         $this->expectException(ValidationException::class);
         $findApiKey->shouldBeCalledOnce();
@@ -56,7 +58,7 @@ class SingleStepCreateShortUrlActionTest extends TestCase
     public function errorResponseIsReturnedIfNoUrlIsProvided(): void
     {
         $request = (new ServerRequest())->withQueryParams(['apiKey' => 'abc123']);
-        $findApiKey = $this->apiKeyService->check('abc123')->willReturn(true);
+        $findApiKey = $this->apiKeyService->check('abc123')->willReturn(new ApiKeyCheckResult(new ApiKey()));
 
         $this->expectException(ValidationException::class);
         $findApiKey->shouldBeCalledOnce();
@@ -67,18 +69,21 @@ class SingleStepCreateShortUrlActionTest extends TestCase
     /** @test */
     public function properDataIsPassedWhenGeneratingShortCode(): void
     {
+        $apiKey = new ApiKey();
+        $key = $apiKey->toString();
+
         $request = (new ServerRequest())->withQueryParams([
-            'apiKey' => 'abc123',
+            'apiKey' => $key,
             'longUrl' => 'http://foobar.com',
         ]);
-        $findApiKey = $this->apiKeyService->check('abc123')->willReturn(true);
+        $findApiKey = $this->apiKeyService->check($key)->willReturn(new ApiKeyCheckResult($apiKey));
         $generateShortCode = $this->urlShortener->shorten(
             Argument::that(function (string $argument): string {
                 Assert::assertEquals('http://foobar.com', $argument);
                 return $argument;
             }),
             [],
-            ShortUrlMeta::fromRawData(['apiKey' => 'abc123']),
+            ShortUrlMeta::fromRawData(['apiKey' => $key]),
         )->willReturn(new ShortUrl(''));
 
         $resp = $this->action->handle($request);
diff --git a/module/Rest/test/Middleware/AuthenticationMiddlewareTest.php b/module/Rest/test/Middleware/AuthenticationMiddlewareTest.php
index db721780..39559f67 100644
--- a/module/Rest/test/Middleware/AuthenticationMiddlewareTest.php
+++ b/module/Rest/test/Middleware/AuthenticationMiddlewareTest.php
@@ -18,9 +18,11 @@ use Psr\Http\Message\ServerRequestInterface;
 use Psr\Http\Server\MiddlewareInterface;
 use Psr\Http\Server\RequestHandlerInterface;
 use Shlinkio\Shlink\Rest\Action\HealthAction;
+use Shlinkio\Shlink\Rest\Entity\ApiKey;
 use Shlinkio\Shlink\Rest\Exception\MissingAuthenticationException;
 use Shlinkio\Shlink\Rest\Exception\VerifyAuthenticationException;
 use Shlinkio\Shlink\Rest\Middleware\AuthenticationMiddleware;
+use Shlinkio\Shlink\Rest\Service\ApiKeyCheckResult;
 use Shlinkio\Shlink\Rest\Service\ApiKeyServiceInterface;
 
 use function Laminas\Stratigility\middleware;
@@ -114,7 +116,7 @@ class AuthenticationMiddlewareTest extends TestCase
             )
             ->withHeader('X-Api-Key', $apiKey);
 
-        $this->apiKeyService->check($apiKey)->willReturn(false)->shouldBeCalledOnce();
+        $this->apiKeyService->check($apiKey)->willReturn(new ApiKeyCheckResult())->shouldBeCalledOnce();
         $this->handler->handle($request)->shouldNotBeCalled();
         $this->expectException(VerifyAuthenticationException::class);
         $this->expectExceptionMessage('Provided API key does not exist or is invalid');
@@ -125,16 +127,17 @@ class AuthenticationMiddlewareTest extends TestCase
     /** @test */
     public function validApiKeyFallsBackToNextMiddleware(): void
     {
-        $apiKey = 'abc123';
+        $apiKey = new ApiKey();
+        $key = $apiKey->toString();
         $request = ServerRequestFactory::fromGlobals()
             ->withAttribute(
                 RouteResult::class,
                 RouteResult::fromRoute(new Route('bar', $this->getDummyMiddleware()), []),
             )
-            ->withHeader('X-Api-Key', $apiKey);
+            ->withHeader('X-Api-Key', $key);
 
-        $handle = $this->handler->handle($request)->willReturn(new Response());
-        $checkApiKey = $this->apiKeyService->check($apiKey)->willReturn(true);
+        $handle = $this->handler->handle($request->withAttribute(ApiKey::class, $apiKey))->willReturn(new Response());
+        $checkApiKey = $this->apiKeyService->check($key)->willReturn(new ApiKeyCheckResult($apiKey));
 
         $this->middleware->process($request, $this->handler->reveal());
 
diff --git a/module/Rest/test/Service/ApiKeyServiceTest.php b/module/Rest/test/Service/ApiKeyServiceTest.php
index 656541f0..6d228661 100644
--- a/module/Rest/test/Service/ApiKeyServiceTest.php
+++ b/module/Rest/test/Service/ApiKeyServiceTest.php
@@ -59,7 +59,10 @@ class ApiKeyServiceTest extends TestCase
                                             ->shouldBeCalledOnce();
         $this->em->getRepository(ApiKey::class)->willReturn($repo->reveal());
 
-        self::assertFalse($this->service->check('12345'));
+        $result = $this->service->check('12345');
+
+        self::assertFalse($result->isValid());
+        self::assertSame($invalidKey, $result->apiKey());
     }
 
     public function provideInvalidApiKeys(): iterable
@@ -72,12 +75,17 @@ class ApiKeyServiceTest extends TestCase
     /** @test */
     public function checkReturnsTrueWhenConditionsAreFavorable(): void
     {
+        $apiKey = new ApiKey();
+
         $repo = $this->prophesize(EntityRepository::class);
-        $repo->findOneBy(['key' => '12345'])->willReturn(new ApiKey())
+        $repo->findOneBy(['key' => '12345'])->willReturn($apiKey)
                                             ->shouldBeCalledOnce();
         $this->em->getRepository(ApiKey::class)->willReturn($repo->reveal());
 
-        self::assertTrue($this->service->check('12345'));
+        $result = $this->service->check('12345');
+
+        self::assertTrue($result->isValid());
+        self::assertSame($apiKey, $result->apiKey());
     }
 
     /** @test */