diff --git a/app/Features/Invoice/UpdateInvoice/BaseUpdateInvoiceValidator.php b/app/Features/Invoice/UpdateInvoice/BaseUpdateInvoiceValidator.php
index 5a856a6..9f1814e 100644
--- a/app/Features/Invoice/UpdateInvoice/BaseUpdateInvoiceValidator.php
+++ b/app/Features/Invoice/UpdateInvoice/BaseUpdateInvoiceValidator.php
@@ -13,7 +13,7 @@
 
 final class BaseUpdateInvoiceValidator implements UpdateInvoiceValidator
 {
-    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice): void
+    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice, array $headers): void
     {
         if (!$data) {
             throw new ValidationFailed('Missing data');
diff --git a/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidator.php b/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidator.php
new file mode 100644
index 0000000..1b744ce
--- /dev/null
+++ b/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidator.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Features\Invoice\UpdateInvoice;
+
+use App\Shared\Exceptions\SignatureVerificationFailed;
+use App\Features\Shared\Configuration\BitPayConfigurationInterface;
+use Psr\Log\LoggerInterface;
+use RuntimeException;
+
+final class BitPaySignatureValidator
+{
+    public const MISSING_SIGNATURE_MESSAGE = 'Missing signature header';
+    public const INVALID_SIGNATURE_MESSAGE = 'Invalid signature';
+    public const MISSING_TOKEN_MESSAGE = 'Invalid BitPay configuration - missing token';
+
+    private BitPayConfigurationInterface $bitpayConfiguration;
+    public function __construct(
+        BitPayConfigurationInterface $bitpayConfiguration,
+    ) {
+        $this->bitpayConfiguration = $bitpayConfiguration;
+    }
+
+    public function execute(array $data, array $headers): void
+    {
+        $token = $this->bitpayConfiguration->getToken();
+
+        if (!$token) {
+            throw new RuntimeException(self::MISSING_TOKEN_MESSAGE);
+        }
+
+        $sigHeader = $headers['x-signature'][0] ?? null;
+
+        if (!$sigHeader) {
+            throw new SignatureVerificationFailed(self::MISSING_SIGNATURE_MESSAGE);
+        }
+
+        $hmac = base64_encode(hash_hmac(
+            'sha256',
+            json_encode($data),
+            $token,
+            true
+        ));
+
+        if ($sigHeader !== $hmac) {
+            throw new SignatureVerificationFailed(self::INVALID_SIGNATURE_MESSAGE);
+        }
+    }
+}
diff --git a/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidatorInterface.php b/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidatorInterface.php
new file mode 100644
index 0000000..1b0512a
--- /dev/null
+++ b/app/Features/Invoice/UpdateInvoice/BitPaySignatureValidatorInterface.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Features\Invoice\UpdateInvoice;
+
+interface BitPaySignatureValidatorInterface
+{
+    /**
+     * Validates the BitPay signature against the provided data and headers
+     *
+     * @param array $data The payload data to validate
+     * @param array $headers The headers containing the signature - x-signature
+     *
+     * @throws \App\Shared\Exceptions\SignatureVerificationFailed When signature is missing or invalid
+     * @throws \RuntimeException When BitPay token is missing
+     */
+    public function execute(array $data, array $headers): void;
+}
diff --git a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceIpnValidator.php b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceIpnValidator.php
index 86b6341..b93f602 100644
--- a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceIpnValidator.php
+++ b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceIpnValidator.php
@@ -20,17 +20,23 @@ final class UpdateInvoiceIpnValidator implements UpdateInvoiceValidator
 
     private UpdateInvoiceValidator $updateInvoiceValidator;
     private Logger $logger;
+    private BitPaySignatureValidator $bitPaySignatureValidator;
 
-    public function __construct(UpdateInvoiceValidator $updateInvoiceValidator, Logger $logger)
-    {
+    public function __construct(
+        UpdateInvoiceValidator $updateInvoiceValidator,
+        Logger $logger,
+        BitPaySignatureValidator $bitPaySignatureValidator
+    ) {
         $this->updateInvoiceValidator = $updateInvoiceValidator;
         $this->logger = $logger;
+        $this->bitPaySignatureValidator = $bitPaySignatureValidator;
     }
 
-    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice): void
+    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice, ?array $headers): void
     {
         try {
-            $this->updateInvoiceValidator->execute($data, $bitPayInvoice);
+            $this->bitPaySignatureValidator->execute($data, $headers);
+            $this->updateInvoiceValidator->execute($data, $bitPayInvoice, $headers);
 
             if (!$bitPayInvoice) {
                 throw new ValidationFailed(self::MISSING_BITPAY_MESSAGE);
diff --git a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceUsingBitPayIpn.php b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceUsingBitPayIpn.php
index 4543884..52e46c1 100644
--- a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceUsingBitPayIpn.php
+++ b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceUsingBitPayIpn.php
@@ -16,6 +16,7 @@
 use App\Models\Invoice\InvoicePayment;
 use App\Models\Invoice\InvoicePaymentCurrency;
 use App\Models\Invoice\InvoiceRepositoryInterface;
+use App\Shared\Exceptions\SignatureVerificationFailed;
 
 class UpdateInvoiceUsingBitPayIpn
 {
@@ -45,7 +46,7 @@ public function __construct(
         $this->bitPayConfiguration = $bitPayConfiguration;
     }
 
-    public function execute(string $uuid, array $data): void
+    public function execute(string $uuid, array $data, array $headers): void
     {
         $invoice = $this->invoiceRepository->findOneByUuid($uuid);
         if (!$invoice) {
@@ -54,6 +55,7 @@ public function execute(string $uuid, array $data): void
 
         try {
             $client = $this->bitPayClientFactory->create();
+
             $bitPayInvoice = $client->getInvoice(
                 $invoice->getBitpayId(),
                 $this->bitPayConfiguration->getFacade(),
@@ -61,11 +63,13 @@ public function execute(string $uuid, array $data): void
             );
 
             $updateInvoiceData = $this->bitPayUpdateMapper->execute($data)->toArray();
-            $this->updateInvoiceValidator->execute($data, $bitPayInvoice);
+            $this->updateInvoiceValidator->execute($data, $bitPayInvoice, $headers);
 
             $this->updateInvoice($invoice, $updateInvoiceData);
 
             $this->sendUpdateInvoiceNotification->execute($invoice, $data['event'] ?? null);
+        } catch (SignatureVerificationFailed $e) {
+            throw $e;
         } catch (\Exception | \TypeError $e) {
             $this->logger->error('INVOICE_UPDATE_FAIL', 'Failed to update invoice', [
                 'id' => $invoice->id
diff --git a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceValidator.php b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceValidator.php
index 87b8cf1..6221bec 100644
--- a/app/Features/Invoice/UpdateInvoice/UpdateInvoiceValidator.php
+++ b/app/Features/Invoice/UpdateInvoice/UpdateInvoiceValidator.php
@@ -16,5 +16,5 @@ interface UpdateInvoiceValidator
     /**
      * @throws ValidationFailed
      */
-    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice): void;
+    public function execute(?array $data, ?BitPayInvoice $bitPayInvoice, array $headers): void;
 }
diff --git a/app/Http/Controllers/Invoice/UpdateInvoiceController.php b/app/Http/Controllers/Invoice/UpdateInvoiceController.php
index 2c2c3f7..331b154 100644
--- a/app/Http/Controllers/Invoice/UpdateInvoiceController.php
+++ b/app/Http/Controllers/Invoice/UpdateInvoiceController.php
@@ -14,6 +14,7 @@
 use App\Http\Controllers\Controller;
 use Illuminate\Http\Request;
 use Symfony\Component\HttpFoundation\Response;
+use App\Shared\Exceptions\SignatureVerificationFailed;
 
 class UpdateInvoiceController extends Controller
 {
@@ -30,17 +31,19 @@ public function execute(Request $request, string $uuid): Response
     {
         $this->logger->info('IPN_RECEIVED', 'Received IPN', $request->request->all());
 
-        /** @var array $data */
-        $data = $request->request->get('data');
-        $event = $request->request->get('event');
+        $payload = json_decode($request->getContent(), true);
+        $data = $payload['data'];
+        $event = $payload['event'];
 
         $data['uuid'] = $uuid;
         $data['event'] = $event['name'] ?? null;
 
         try {
-            $this->updateInvoice->execute($uuid, $data);
+            $this->updateInvoice->execute($uuid, $data, $request->headers->all());
         } catch (MissingInvoice $e) {
             return response(null, Response::HTTP_NOT_FOUND);
+        } catch (SignatureVerificationFailed $e) {
+            return response($e->getMessage(), Response::HTTP_UNAUTHORIZED);
         } catch (\Exception $e) {
             return response('Unable to process update', Response::HTTP_BAD_REQUEST);
         }
diff --git a/app/Infrastructure/Laravel/AppServiceProvider.php b/app/Infrastructure/Laravel/AppServiceProvider.php
index 5c645cb..a9bd422 100644
--- a/app/Infrastructure/Laravel/AppServiceProvider.php
+++ b/app/Infrastructure/Laravel/AppServiceProvider.php
@@ -17,6 +17,8 @@
 use App\Features\Invoice\UpdateInvoice\SendUpdateInvoiceEventStream;
 use App\Features\Invoice\UpdateInvoice\UpdateInvoiceIpnValidator;
 use App\Features\Invoice\UpdateInvoice\UpdateInvoiceValidator;
+use App\Features\Invoice\UpdateInvoice\BitPaySignatureValidator;
+use App\Features\Invoice\UpdateInvoice\BitPaySignatureValidatorInterface;
 use App\Features\Shared\Logger;
 use App\Features\Shared\SseConfiguration;
 use App\Features\Shared\UrlProvider;
@@ -87,12 +89,18 @@ function () {
             SseMercureConfiguration::class
         );
 
+        $this->app->bind(
+            BitPaySignatureValidatorInterface::class,
+            BitPaySignatureValidator::class
+        );
+
         $this->app->bind(
             UpdateInvoiceIpnValidator::class,
             function () {
                 return new UpdateInvoiceIpnValidator(
                     $this->app->make(BaseUpdateInvoiceValidator::class),
-                    $this->app->make(Logger::class)
+                    $this->app->make(Logger::class),
+                    $this->app->make(BitPaySignatureValidator::class)
                 );
             }
         );
diff --git a/app/Shared/Exceptions/SignatureVerificationFailed.php b/app/Shared/Exceptions/SignatureVerificationFailed.php
new file mode 100644
index 0000000..3a9a611
--- /dev/null
+++ b/app/Shared/Exceptions/SignatureVerificationFailed.php
@@ -0,0 +1,13 @@
+<?php
+
+/**
+ * Copyright (c) 2019 BitPay
+ **/
+
+declare(strict_types=1);
+
+namespace App\Shared\Exceptions;
+
+class SignatureVerificationFailed extends \RuntimeException
+{
+}
diff --git a/routes/web.php b/routes/web.php
index d1194b0..b7fe213 100644
--- a/routes/web.php
+++ b/routes/web.php
@@ -23,4 +23,3 @@
 Route::post('/invoices', [CreateInvoiceController::class, 'execute'])->name('createInvoice');
 Route::get('/invoices/{id}', [GetInvoiceViewController::class, 'execute'])->name('invoiceView');
 Route::post('/invoices/{uuid}', [UpdateInvoiceController::class, 'execute'])->name('updateInvoice');
-
diff --git a/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTest.php b/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTest.php
new file mode 100644
index 0000000..c54c2b9
--- /dev/null
+++ b/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTest.php
@@ -0,0 +1,233 @@
+<?php
+
+/**
+ * Copyright (c) 2019 BitPay
+ **/
+
+declare(strict_types=1);
+
+namespace Tests\Integration\Features\Invoice\UpdateInvoice;
+
+use App\Features\Invoice\UpdateInvoice\SendUpdateInvoiceEventStream;
+use App\Features\Invoice\UpdateInvoice\UpdateInvoiceUsingBitPayIpn;
+use App\Features\Shared\BitPayClientFactory;
+use App\Models\Invoice\InvoiceRepositoryInterface;
+use BitPaySDK\Model\Facade;
+use BitPaySDK\Model\Invoice\Invoice;
+use BitPaySDK\PosClient;
+use Mockery\MockInterface;
+use PHPUnit\Framework\Assert;
+use Tests\ExampleInvoice;
+use Tests\Integration\IntegrationTestCase;
+use App\Features\Invoice\UpdateInvoice\BitPaySignatureValidator;
+use App\Features\Shared\Configuration\BitPayConfigurationInterface;
+use App\Features\Shared\Configuration\Design;
+use RuntimeException;
+
+class UpdateInvoiceTest extends IntegrationTestCase
+{
+    /**
+     * @test
+     */
+    public function it_should_update_invoice_and_send_update_notification()
+    {
+        $fileData = file_get_contents(__DIR__ . DIRECTORY_SEPARATOR . 'bitPayUpdate.json');
+        $data = json_decode($fileData, true, 512, JSON_THROW_ON_ERROR);
+
+        ExampleInvoice::createSaved();
+
+        $this->mock(BitPayClientFactory::class, function (MockInterface $mock) {
+            $mock->shouldReceive('create')->andReturn(new class ('', '') extends PosClient {
+                public function getInvoice(
+                    string $invoiceId,
+                    string $facade = Facade::Merchant,
+                    bool $signRequest = true
+                ): Invoice {
+                    $invoice = new Invoice();
+                    $invoice->setId(ExampleInvoice::BITPAY_ID);
+                    $invoice->setOrderId(ExampleInvoice::BITPAY_ORDER_ID);
+
+                    return $invoice;
+                }
+            });
+        });
+        $this->mock(SendUpdateInvoiceEventStream::class, function (MockInterface $mock) {
+            $mock->shouldReceive('execute')->times(1);
+        });
+        $this->mock(BitPayConfigurationInterface::class, function (MockInterface $mock) {
+            $mock->shouldReceive('getToken')->andReturn(ExampleInvoice::TOKEN);
+            $mock->shouldReceive('getDesign')->andReturn($this->createStub(Design::class));
+            $mock->shouldReceive('getFacade')->andReturn(Facade::MERCHANT);
+            $mock->shouldReceive('isSignRequest')->andReturn(true);
+        });
+
+        $testedClass = $this->getTestedClass();
+        $signature = base64_encode(hash_hmac('sha256', json_encode($data), ExampleInvoice::TOKEN, true));
+        $testedClass->execute(ExampleInvoice::UUID, $data, ['x-signature' => [$signature]]);
+
+        $invoice = $this->app->make(InvoiceRepositoryInterface::class)->findOne(1);
+
+        Assert::assertEquals(ExampleInvoice::TOKEN, $invoice->token);
+        Assert::assertEquals('someBitpayId', $invoice->bitpay_id);
+        Assert::assertEquals('https://test.bitpay.com/invoice?id=MV9fy5iNDkqrg4qrfYpw75', $invoice->bitpay_url);
+        // phpcs:disable Generic.Files.LineLength.TooLong
+        Assert::assertEquals("{\"store\":\"store-1\",\"register\":\"2\",\"reg_transaction_no\":\"87678\",\"price\":\"76.70\"}", $invoice->pos_data_json);
+        Assert::assertEquals('expired', $invoice->status);
+        Assert::assertEquals(76.7, $invoice->price);
+        Assert::assertEquals('USD', $invoice->currency_code);
+        Assert::assertEquals('false', $invoice->exception_status);
+
+        $eth = $invoice->getInvoicePayment()->paymentCurrencies()->where('currency_code', 'ETH')->first();
+        $btc = $invoice->getInvoicePayment()->paymentCurrencies()->where('currency_code', 'BTC')->first();
+        Assert::assertEquals(48312000000000000, $eth->total);
+        Assert::assertEquals(48312000000000000, $eth->subtotal);
+        Assert::assertEquals(347100, $btc->total);
+        Assert::assertEquals(342800, $btc->subtotal);
+        Assert::assertEquals(0, $invoice->getInvoicePayment()->amount_paid);
+        Assert::assertEquals('someBitpayOrderId', $invoice->bitpay_order_id);
+    }
+
+    /**
+     * @test
+     */
+    public function it_should_fail_updating_invoice_with_invalid_webhook_signature(): void
+    {
+        // given
+        $fileData = file_get_contents(__DIR__ . DIRECTORY_SEPARATOR . 'bitPayUpdate.json');
+        $data = json_decode($fileData, true, 512, JSON_THROW_ON_ERROR);
+
+        ExampleInvoice::createSaved();
+
+        $this->mock(BitPayClientFactory::class, function (MockInterface $mock) {
+            $mock->shouldReceive('create')->andReturn(new class ('', '') extends PosClient {
+                public function getInvoice(
+                    string $invoiceId,
+                    string $facade = Facade::Merchant,
+                    bool $signRequest = true
+                ): Invoice {
+                    $invoice = new Invoice();
+                    $invoice->setId(ExampleInvoice::BITPAY_ID);
+                    $invoice->setOrderId(ExampleInvoice::BITPAY_ORDER_ID);
+
+                    return $invoice;
+                }
+            });
+        });
+
+        $this->mock(SendUpdateInvoiceEventStream::class, function (MockInterface $mock) {
+            $mock->shouldReceive('execute')->never();
+        });
+
+        $this->mock(BitPayConfigurationInterface::class, function (MockInterface $mock) {
+            $mock->shouldReceive('getToken')->andReturn(ExampleInvoice::TOKEN);
+            $mock->shouldReceive('getDesign')->andReturn($this->createStub(Design::class));
+            $mock->shouldReceive('getFacade')->andReturn(Facade::MERCHANT);
+            $mock->shouldReceive('isSignRequest')->andReturn(true);
+        });
+
+        $headers = ['x-signature' => ['invalid-signature']];
+
+        $testedClass = $this->getTestedClass();
+
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage(BitPaySignatureValidator::INVALID_SIGNATURE_MESSAGE);
+        $testedClass->execute(ExampleInvoice::UUID, $data, $headers);
+    }
+
+        /**
+     * @test
+     */
+    public function it_should_fail_updating_invoice_with_missing_configuration_token(): void
+    {
+        // given
+        $fileData = file_get_contents(__DIR__ . DIRECTORY_SEPARATOR . 'bitPayUpdate.json');
+        $data = json_decode($fileData, true, 512, JSON_THROW_ON_ERROR);
+
+        ExampleInvoice::createSaved();
+
+        $this->mock(BitPayClientFactory::class, function (MockInterface $mock) {
+            $mock->shouldReceive('create')->andReturn(new class ('', '') extends PosClient {
+                public function getInvoice(
+                    string $invoiceId,
+                    string $facade = Facade::Merchant,
+                    bool $signRequest = true
+                ): Invoice {
+                    $invoice = new Invoice();
+                    $invoice->setId(ExampleInvoice::BITPAY_ID);
+                    $invoice->setOrderId(ExampleInvoice::BITPAY_ORDER_ID);
+
+                    return $invoice;
+                }
+            });
+        });
+
+        $this->mock(SendUpdateInvoiceEventStream::class, function (MockInterface $mock) {
+            $mock->shouldReceive('execute')->never();
+        });
+
+        $this->mock(BitPayConfigurationInterface::class, function (MockInterface $mock) {
+            $mock->shouldReceive('getToken')->andReturn(null);
+            $mock->shouldReceive('getFacade')->andReturn(Facade::MERCHANT);
+            $mock->shouldReceive('isSignRequest')->andReturn(true);
+        });
+
+        // when
+        $testedClass = $this->getTestedClass();
+
+        // then
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage(BitPaySignatureValidator::MISSING_TOKEN_MESSAGE);
+        $testedClass->execute(ExampleInvoice::UUID, $data, [
+            'x-signature' => 'signature'
+        ]);
+    }
+
+    /**
+     * @test
+     */
+    public function it_should_fail_updating_invoice_with_missing_sig_header(): void
+    {
+        // given
+        $fileData = file_get_contents(__DIR__ . DIRECTORY_SEPARATOR . 'bitPayUpdate.json');
+        $data = json_decode($fileData, true, 512, JSON_THROW_ON_ERROR);
+
+        ExampleInvoice::createSaved();
+
+        $this->mock(BitPayClientFactory::class, function (MockInterface $mock) {
+            $mock->shouldReceive('create')->andReturn(new class ('', '') extends PosClient {
+                public function getInvoice(
+                    string $invoiceId,
+                    string $facade = Facade::Merchant,
+                    bool $signRequest = true
+                ): Invoice {
+                    $invoice = new Invoice();
+                    $invoice->setId(ExampleInvoice::BITPAY_ID);
+                    $invoice->setOrderId(ExampleInvoice::BITPAY_ORDER_ID);
+
+                    return $invoice;
+                }
+            });
+        });
+
+        $this->mock(SendUpdateInvoiceEventStream::class, function (MockInterface $mock) {
+            $mock->shouldReceive('execute')->never();
+        });
+
+        $this->mock(BitPayConfigurationInterface::class, function (MockInterface $mock) {
+            $mock->shouldReceive('getToken')->andReturn(ExampleInvoice::TOKEN);
+            $mock->shouldReceive('getFacade')->andReturn(Facade::MERCHANT);
+            $mock->shouldReceive('isSignRequest')->andReturn(true);
+        });
+
+        $testedClass = $this->getTestedClass();
+
+        $this->expectException(RuntimeException::class);
+        $this->expectExceptionMessage(BitPaySignatureValidator::MISSING_SIGNATURE_MESSAGE);
+        $testedClass->execute(ExampleInvoice::UUID, $data, []); // Empty headers array
+    }
+
+    private function getTestedClass(): UpdateInvoiceUsingBitPayIpn
+    {
+        return $this->app->make(UpdateInvoiceUsingBitPayIpn::class);
+    }
+}
diff --git a/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTestCase.php b/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTestCase.php
deleted file mode 100644
index 6600449..0000000
--- a/tests/Integration/Features/Invoice/UpdateInvoice/UpdateInvoiceTestCase.php
+++ /dev/null
@@ -1,83 +0,0 @@
-<?php
-
-/**
- * Copyright (c) 2019 BitPay
- **/
-
-declare(strict_types=1);
-
-namespace Tests\Integration\Features\Invoice\UpdateInvoice;
-
-use App\Features\Invoice\UpdateInvoice\SendUpdateInvoiceEventStream;
-use App\Features\Invoice\UpdateInvoice\UpdateInvoiceUsingBitPayIpn;
-use App\Features\Shared\BitPayClientFactory;
-use App\Models\Invoice\InvoiceRepositoryInterface;
-use BitPaySDK\Model\Facade;
-use BitPaySDK\Model\Invoice\Invoice;
-use BitPaySDK\PosClient;
-use Mockery\MockInterface;
-use PHPUnit\Framework\Assert;
-use Tests\ExampleInvoice;
-use Tests\Integration\IntegrationTestCase;
-
-class UpdateInvoiceTestCase extends IntegrationTestCase
-{
-    /**
-     * @test
-     */
-    public function it_should_update_invoice_and_send_update_notification()
-    {
-        $fileData = file_get_contents(__DIR__ . DIRECTORY_SEPARATOR . 'bitPayUpdate.json');
-        $data = json_decode($fileData, true, 512, JSON_THROW_ON_ERROR);
-
-        ExampleInvoice::createSaved();
-
-        $this->mock(BitPayClientFactory::class, function (MockInterface $mock) {
-            $mock->shouldReceive('create')->andReturn(new class ('', '') extends PosClient {
-                public function getInvoice(
-                    string $invoiceId,
-                    string $facade = Facade::Merchant,
-                    bool $signRequest = true
-                ): Invoice {
-                    $invoice = new Invoice();
-                    $invoice->setId(ExampleInvoice::BITPAY_ID);
-                    $invoice->setOrderId(ExampleInvoice::BITPAY_ORDER_ID);
-
-                    return $invoice;
-                }
-            });
-        });
-        $this->mock(SendUpdateInvoiceEventStream::class, function (MockInterface $mock) {
-            $mock->shouldReceive('execute')->times(1);
-        });
-
-        $testedClass = $this->getTestedClass();
-        $testedClass->execute(ExampleInvoice::UUID, $data);
-
-        $invoice = $this->app->make(InvoiceRepositoryInterface::class)->findOne(1);
-
-        Assert::assertEquals(ExampleInvoice::TOKEN, $invoice->token);
-        Assert::assertEquals('someBitpayId', $invoice->bitpay_id);
-        Assert::assertEquals('https://test.bitpay.com/invoice?id=MV9fy5iNDkqrg4qrfYpw75', $invoice->bitpay_url);
-        // phpcs:disable Generic.Files.LineLength.TooLong
-        Assert::assertEquals("{\"store\":\"store-1\",\"register\":\"2\",\"reg_transaction_no\":\"87678\",\"price\":\"76.70\"}", $invoice->pos_data_json);
-        Assert::assertEquals('expired', $invoice->status);
-        Assert::assertEquals(76.7, $invoice->price);
-        Assert::assertEquals('USD', $invoice->currency_code);
-        Assert::assertEquals('false', $invoice->exception_status);
-
-        $eth = $invoice->getInvoicePayment()->paymentCurrencies()->where('currency_code', 'ETH')->first();
-        $btc = $invoice->getInvoicePayment()->paymentCurrencies()->where('currency_code', 'BTC')->first();
-        Assert::assertEquals(48312000000000000, $eth->total);
-        Assert::assertEquals(48312000000000000, $eth->subtotal);
-        Assert::assertEquals(347100, $btc->total);
-        Assert::assertEquals(342800, $btc->subtotal);
-        Assert::assertEquals(0, $invoice->getInvoicePayment()->amount_paid);
-        Assert::assertEquals('someBitpayOrderId', $invoice->bitpay_order_id);
-    }
-
-    private function getTestedClass(): UpdateInvoiceUsingBitPayIpn
-    {
-        return $this->app->make(UpdateInvoiceUsingBitPayIpn::class);
-    }
-}
diff --git a/tests/Unit/Features/Invoice/UpdateInvoice/ValidateBitPayWebhookTest.php b/tests/Unit/Features/Invoice/UpdateInvoice/ValidateBitPayWebhookTest.php
new file mode 100644
index 0000000..36ef579
--- /dev/null
+++ b/tests/Unit/Features/Invoice/UpdateInvoice/ValidateBitPayWebhookTest.php
@@ -0,0 +1,78 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Unit\Features\Invoice\UpdateInvoice;
+
+use App\Features\Shared\Configuration\BitPayConfigurationInterface;
+use App\Features\Invoice\UpdateInvoice\BitPaySignatureValidator;
+use Tests\Unit\AbstractUnitTestCase;
+
+class ValidateBitPayWebhookTest extends AbstractUnitTestCase
+{
+    /**
+     * @test
+     */
+    public function it_should_return_error_when_signing_key_is_missing(): void
+    {
+        $bitpayConfig = $this->createMock(BitPayConfigurationInterface::class);
+        $bitpayConfig->expects($this->once())
+            ->method('getToken')
+            ->willReturn(null);
+
+        $validator = new BitPaySignatureValidator($bitpayConfig);
+        $this->expectException(\RuntimeException::class);
+        $validator->execute([], [
+            'x-signature' => 'test-signature',
+        ]);
+    }
+
+    /**
+     * @test
+     */
+    public function it_should_return_error_when_signature_header_is_missing(): void
+    {
+        $bitpayConfig = $this->createMock(BitPayConfigurationInterface::class);
+        $validator = new BitPaySignatureValidator($bitpayConfig);
+        $this->expectException(\RuntimeException::class);
+
+        $validator->execute([], []);
+    }
+
+    /**
+     * @test
+     */
+    public function it_should_return_error_when_signature_does_not_match(): void
+    {
+        $bitpayConfig = $this->createMock(BitPayConfigurationInterface::class);
+        $bitpayConfig->expects($this->once())
+            ->method('getToken')
+            ->willReturn('test-token');
+
+        $headers = ['x-signature' => 'invalid-signature'];
+
+        $validator = new BitPaySignatureValidator($bitpayConfig);
+        $this->expectException(\RuntimeException::class);
+        $validator->execute([], $headers);
+    }
+
+    /**
+     * @test
+     */
+    public function it_should_allow_request_when_signature_is_valid(): void
+    {
+        $token = 'test-token';
+        $testContent = ['test-content'];
+
+        $bitpayConfig = $this->createMock(BitPayConfigurationInterface::class);
+        $bitpayConfig->expects($this->once())
+            ->method('getToken')
+            ->willReturn($token);
+
+        $expectedSignature = base64_encode(hash_hmac('sha256', json_encode($testContent), $token, true));
+
+        $validator = new BitPaySignatureValidator($bitpayConfig);
+
+        $validator->execute($testContent, ['x-signature' => [$expectedSignature]]);
+    }
+}