diff --git a/DependencyInjection/Security/OAuth2Factory.php b/DependencyInjection/Security/OAuth2Factory.php
index dc4404bb..30c2fa77 100644
--- a/DependencyInjection/Security/OAuth2Factory.php
+++ b/DependencyInjection/Security/OAuth2Factory.php
@@ -23,11 +23,13 @@ public function create(ContainerBuilder $container, $id, $config, $userProvider,
         $providerId = 'security.authentication.provider.oauth2.' . $id;
         $container
             ->setDefinition($providerId, new ChildDefinition(OAuth2Provider::class))
-            ->replaceArgument('$userProvider', new Reference($userProvider));
+            ->replaceArgument('$userProvider', new Reference($userProvider))
+            ->replaceArgument('$providerKey', $id);
 
         $listenerId = 'security.authentication.listener.oauth2.' . $id;
         $container
-            ->setDefinition($listenerId, new ChildDefinition(OAuth2Listener::class));
+            ->setDefinition($listenerId, new ChildDefinition(OAuth2Listener::class))
+            ->replaceArgument('$providerKey', $id);
 
         return [$providerId, $listenerId, OAuth2EntryPoint::class];
     }
diff --git a/Security/Authentication/Provider/OAuth2Provider.php b/Security/Authentication/Provider/OAuth2Provider.php
index f4a86652..3528b2e7 100644
--- a/Security/Authentication/Provider/OAuth2Provider.php
+++ b/Security/Authentication/Provider/OAuth2Provider.php
@@ -32,11 +32,21 @@ final class OAuth2Provider implements AuthenticationProviderInterface
      */
     private $oauth2TokenFactory;
 
-    public function __construct(UserProviderInterface $userProvider, ResourceServer $resourceServer, OAuth2TokenFactory $oauth2TokenFactory)
-    {
+    /**
+     * @var string
+     */
+    private $providerKey;
+
+    public function __construct(
+        UserProviderInterface $userProvider,
+        ResourceServer $resourceServer,
+        OAuth2TokenFactory $oauth2TokenFactory,
+        string $providerKey
+    ) {
         $this->userProvider = $userProvider;
         $this->resourceServer = $resourceServer;
         $this->oauth2TokenFactory = $oauth2TokenFactory;
+        $this->providerKey = $providerKey;
     }
 
     /**
@@ -60,7 +70,7 @@ public function authenticate(TokenInterface $token)
             $request->getAttribute('oauth_user_id')
         );
 
-        $token = $this->oauth2TokenFactory->createOAuth2Token($request, $user);
+        $token = $this->oauth2TokenFactory->createOAuth2Token($request, $user, $this->providerKey);
         $token->setAuthenticated(true);
 
         return $token;
@@ -71,7 +81,7 @@ public function authenticate(TokenInterface $token)
      */
     public function supports(TokenInterface $token)
     {
-        return $token instanceof OAuth2Token;
+        return $token instanceof OAuth2Token && $this->providerKey === $token->getProviderKey();
     }
 
     private function getAuthenticatedUser(string $userIdentifier): ?UserInterface
diff --git a/Security/Authentication/Token/OAuth2Token.php b/Security/Authentication/Token/OAuth2Token.php
index 028232c9..9af825c8 100644
--- a/Security/Authentication/Token/OAuth2Token.php
+++ b/Security/Authentication/Token/OAuth2Token.php
@@ -10,8 +10,17 @@
 
 final class OAuth2Token extends AbstractToken
 {
-    public function __construct(ServerRequestInterface $serverRequest, ?UserInterface $user, string $rolePrefix)
-    {
+    /**
+     * @var string
+     */
+    private $providerKey;
+
+    public function __construct(
+        ServerRequestInterface $serverRequest,
+        ?UserInterface $user,
+        string $rolePrefix,
+        string $providerKey
+    ) {
         $this->setAttribute('server_request', $serverRequest);
         $this->setAttribute('role_prefix', $rolePrefix);
 
@@ -25,6 +34,8 @@ public function __construct(ServerRequestInterface $serverRequest, ?UserInterfac
         }
 
         parent::__construct(array_unique($roles));
+
+        $this->providerKey = $providerKey;
     }
 
     /**
@@ -35,6 +46,61 @@ public function getCredentials()
         return $this->getAttribute('server_request')->getAttribute('oauth_access_token_id');
     }
 
+    public function getProviderKey(): string
+    {
+        return $this->providerKey;
+    }
+
+    public function __serialize(): array
+    {
+        if (method_exists(parent::class, '__serialize')) {
+            // this code path should be the only code path after dropping support for Symfony 3.4
+            return [$this->providerKey, parent::__serialize()];
+        }
+
+        return [$this->providerKey, $this->getUser(), $this->isAuthenticated(), $this->getRoles(), $this->getAttributes()];
+    }
+
+    public function __unserialize(array $data): void
+    {
+        if (method_exists(parent::class, '__unserialize')) {
+            // this code path should be the only code path after dropping support for Symfony 3.4
+            [$this->providerKey, $parentData] = $data;
+            parent::__unserialize($parentData);
+
+            return;
+        }
+
+        [$this->providerKey] = $data;
+
+        unset($data[0]);
+
+        parent::unserialize(array_values($data));
+    }
+
+    /**
+     *  This entire function can be removed when dropping support for Symfony 3.4
+     */
+    public function serialize()
+    {
+        $serialized = [$this->providerKey, parent::serialize(true)];
+
+        if (method_exists(parent::class, 'doSerialize')) {
+            return $this->doSerialize($serialized, \func_num_args() ? func_get_arg(0) : null);
+        }
+
+        return serialize($serialized);
+    }
+
+    /**
+     *  This entire function can be removed when dropping support for Symfony 3.4
+     */
+    public function unserialize($serialized)
+    {
+        [$this->providerKey, $parentStr] = \is_array($serialized) ? $serialized : unserialize($serialized);
+        parent::unserialize($parentStr);
+    }
+
     private function buildRolesFromScopes(): array
     {
         $prefix = $this->getAttribute('role_prefix');
diff --git a/Security/Authentication/Token/OAuth2TokenFactory.php b/Security/Authentication/Token/OAuth2TokenFactory.php
index 3144f172..61419706 100644
--- a/Security/Authentication/Token/OAuth2TokenFactory.php
+++ b/Security/Authentication/Token/OAuth2TokenFactory.php
@@ -19,8 +19,8 @@ public function __construct(string $rolePrefix)
         $this->rolePrefix = $rolePrefix;
     }
 
-    public function createOAuth2Token(ServerRequestInterface $serverRequest, ?UserInterface $user): OAuth2Token
+    public function createOAuth2Token(ServerRequestInterface $serverRequest, ?UserInterface $user, string $providerKey): OAuth2Token
     {
-        return new OAuth2Token($serverRequest, $user, $this->rolePrefix);
+        return new OAuth2Token($serverRequest, $user, $this->rolePrefix, $providerKey);
     }
 }
diff --git a/Security/Firewall/OAuth2Listener.php b/Security/Firewall/OAuth2Listener.php
index 7691a96f..c481ffbc 100644
--- a/Security/Firewall/OAuth2Listener.php
+++ b/Security/Firewall/OAuth2Listener.php
@@ -38,16 +38,23 @@ final class OAuth2Listener implements ListenerInterface
      */
     private $oauth2TokenFactory;
 
+    /**
+     * @var string
+     */
+    private $providerKey;
+
     public function __construct(
         TokenStorageInterface $tokenStorage,
         AuthenticationManagerInterface $authenticationManager,
         HttpMessageFactoryInterface $httpMessageFactory,
-        OAuth2TokenFactory $oauth2TokenFactory
+        OAuth2TokenFactory $oauth2TokenFactory,
+        string $providerKey
     ) {
         $this->tokenStorage = $tokenStorage;
         $this->authenticationManager = $authenticationManager;
         $this->httpMessageFactory = $httpMessageFactory;
         $this->oauth2TokenFactory = $oauth2TokenFactory;
+        $this->providerKey = $providerKey;
     }
 
     /**
@@ -68,7 +75,7 @@ public function __invoke(GetResponseEvent $event)
 
         try {
             /** @var OAuth2Token $authenticatedToken */
-            $authenticatedToken = $this->authenticationManager->authenticate($this->oauth2TokenFactory->createOAuth2Token($request, null));
+            $authenticatedToken = $this->authenticationManager->authenticate($this->oauth2TokenFactory->createOAuth2Token($request, null, $this->providerKey));
         } catch (AuthenticationException $e) {
             throw Oauth2AuthenticationFailedException::create($e->getMessage());
         }
diff --git a/Tests/Unit/OAuth2ProviderTest.php b/Tests/Unit/OAuth2ProviderTest.php
new file mode 100644
index 00000000..f1227f2d
--- /dev/null
+++ b/Tests/Unit/OAuth2ProviderTest.php
@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Trikoder\Bundle\OAuth2Bundle\Tests\Unit;
+
+use League\OAuth2\Server\ResourceServer;
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\ServerRequestInterface;
+use Symfony\Component\Security\Core\User\UserProviderInterface;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Provider\OAuth2Provider;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Token\OAuth2Token;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Token\OAuth2TokenFactory;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\FixtureFactory;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\User;
+
+final class OAuth2ProviderTest extends TestCase
+{
+    public function testItSupportsOnlyOAuthTokenWithSameProviderKey(): void
+    {
+        $providerKey = 'foo';
+
+        $tokenFactory = new OAuth2TokenFactory('ROLE_OAUTH2_');
+
+        $provider = new OAuth2Provider(
+            $this->createMock(UserProviderInterface::class),
+            $this->createMock(ResourceServer::class),
+            $tokenFactory,
+            $providerKey
+        );
+
+        $this->assertTrue($provider->supports($this->createToken($tokenFactory, $providerKey)));
+        $this->assertFalse($provider->supports($this->createToken($tokenFactory, $providerKey . 'bar')));
+    }
+
+    private function createToken(OAuth2TokenFactory $tokenFactory, string $providerKey): OAuth2Token
+    {
+        $scopes = [FixtureFactory::FIXTURE_SCOPE_FIRST];
+        $serverRequest = $this->createMock(ServerRequestInterface::class);
+        $serverRequest->expects($this->once())
+            ->method('getAttribute')
+            ->with('oauth_scopes', [])
+            ->willReturn($scopes);
+
+        $user = new User();
+
+        return $tokenFactory->createOAuth2Token($serverRequest, $user, $providerKey);
+    }
+}
diff --git a/Tests/Unit/OAuth2TokenFactoryTest.php b/Tests/Unit/OAuth2TokenFactoryTest.php
new file mode 100644
index 00000000..f2d11370
--- /dev/null
+++ b/Tests/Unit/OAuth2TokenFactoryTest.php
@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Trikoder\Bundle\OAuth2Bundle\Tests\Unit;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\ServerRequestInterface;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Token\OAuth2Token;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Token\OAuth2TokenFactory;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\FixtureFactory;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\User;
+
+final class OAuth2TokenFactoryTest extends TestCase
+{
+    public function testCreatingToken(): void
+    {
+        $rolePrefix = 'ROLE_OAUTH2_';
+        $factory = new OAuth2TokenFactory($rolePrefix);
+
+        $scopes = [FixtureFactory::FIXTURE_SCOPE_FIRST];
+        $serverRequest = $this->createMock(ServerRequestInterface::class);
+        $serverRequest->expects($this->once())
+            ->method('getAttribute')
+            ->with('oauth_scopes', [])
+            ->willReturn($scopes);
+
+        $user = new User();
+        $providerKey = 'main';
+
+        $token = $factory->createOAuth2Token($serverRequest, $user, $providerKey);
+
+        $this->assertInstanceOf(OAuth2Token::class, $token);
+
+        $roles = $token->getRoles();
+        $this->assertCount(1, $roles);
+        $this->assertSame($rolePrefix . strtoupper($scopes[0]), $roles[0]->getRole());
+
+        $this->assertFalse($token->isAuthenticated());
+        $this->assertSame($user, $token->getUser());
+        $this->assertSame($providerKey, $token->getProviderKey());
+    }
+}
diff --git a/Tests/Unit/OAuth2TokenTest.php b/Tests/Unit/OAuth2TokenTest.php
new file mode 100644
index 00000000..f4ad6162
--- /dev/null
+++ b/Tests/Unit/OAuth2TokenTest.php
@@ -0,0 +1,46 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Trikoder\Bundle\OAuth2Bundle\Tests\Unit;
+
+use PHPUnit\Framework\TestCase;
+use Psr\Http\Message\ServerRequestInterface;
+use Trikoder\Bundle\OAuth2Bundle\Security\Authentication\Token\OAuth2Token;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\FixtureFactory;
+use Trikoder\Bundle\OAuth2Bundle\Tests\Fixtures\User;
+
+final class OAuth2TokenTest extends TestCase
+{
+    public function testTokenSerialization(): void
+    {
+        $scopes = [FixtureFactory::FIXTURE_SCOPE_FIRST];
+        $serverRequest = $this->createMock(ServerRequestInterface::class);
+        $serverRequest->expects($this->once())
+            ->method('getAttribute')
+            ->with('oauth_scopes', [])
+            ->willReturn($scopes);
+
+        $user = new User();
+        $rolePrefix = 'ROLE_OAUTH2_';
+        $providerKey = 'main';
+        $token = new OAuth2Token($serverRequest, $user, $rolePrefix, $providerKey);
+
+        /** @var OAuth2Token $unserializedToken */
+        $unserializedToken = unserialize(serialize($token));
+
+        $this->assertSame($providerKey, $unserializedToken->getProviderKey());
+
+        $roles = $unserializedToken->getRoles();
+        $this->assertCount(1, $roles);
+        $expectedRole = $rolePrefix . strtoupper($scopes[0]);
+        $this->assertSame($expectedRole, $roles[0]->getRole());
+
+        $this->assertSame($user->getUsername(), $unserializedToken->getUser()->getUsername());
+        $this->assertFalse($unserializedToken->isAuthenticated());
+
+        if (method_exists($token, 'getRoleNames')) {
+            $this->assertSame([$expectedRole], $token->getRoleNames());
+        }
+    }
+}