diff --git a/documentation/Bruno/Arcadia Api/Api/V1/Employees/List Employees.yml b/documentation/Bruno/Arcadia Api/Api/V1/Employees/List Employees.yml
index 35a7b46..af0844e 100644
--- a/documentation/Bruno/Arcadia Api/Api/V1/Employees/List Employees.yml	
+++ b/documentation/Bruno/Arcadia Api/Api/V1/Employees/List Employees.yml	
@@ -40,6 +40,16 @@ http:
       type: query
       description: Filter by site ID (e.g. LDCSER, SLELA)
       disabled: true
+    - name: siteIds[]
+      value: LDCSER
+      type: query
+      description: Filter by multiple site IDs
+      disabled: true
+    - name: siteIds[]
+      value: SLELA
+      type: query
+      description: Filter by multiple site IDs
+      disabled: true
     - name: serviceId
       value: "097"
       type: query
diff --git a/documentation/OpenApi/openapi.yaml b/documentation/OpenApi/openapi.yaml
index c07f2b2..f5e46aa 100644
--- a/documentation/OpenApi/openapi.yaml
+++ b/documentation/OpenApi/openapi.yaml
@@ -3,7 +3,6 @@ info:
   title: Arcadia API
   description: |
     Arcadia API in order to abstract corporate metamodel to a proper and stable implemented API.
-    Architecture Clean Architecture, Domain-Driven Design (DDD) & Ports & Adapters (Hexagonale).
   contact:
     name: Uwil Engineering Team
     email: digital@ldc.fr
@@ -45,6 +44,7 @@ paths:
         - $ref: '#/components/parameters/Since'
         - $ref: '#/components/parameters/Establishment'
         - $ref: '#/components/parameters/SiteId'
+        - $ref: '#/components/parameters/SiteIds'
         - $ref: '#/components/parameters/ServiceId'
         - $ref: '#/components/parameters/SortBy'
         - $ref: '#/components/parameters/SortDirection'
@@ -207,6 +207,21 @@ components:
         pattern: '^[A-Z]{2,}$'
         example: 'LDCSER'
 
+    SiteIds:
+      name: siteIds
+      in: query
+      required: false
+      description: "Filtrer par un ou plusieurs codes site (ex: siteIds[]=LDCSER&siteIds[]=SLELA)."
+      style: form
+      explode: true
+      schema:
+        type: array
+        minItems: 1
+        items:
+          type: string
+          pattern: '^[A-Z]{2,}$'
+        example: ['LDCSER', 'SLELA']
+
     ServiceId:
       name: serviceId
       in: query
diff --git a/src/Domain/Models/ValueObjects/Employees/EmployeeFilter.php b/src/Domain/Models/ValueObjects/Employees/EmployeeFilter.php
index bc96a6b..d49737f 100644
--- a/src/Domain/Models/ValueObjects/Employees/EmployeeFilter.php
+++ b/src/Domain/Models/ValueObjects/Employees/EmployeeFilter.php
@@ -10,13 +10,20 @@ use Domain\Models\ValueObjects\SiteId;
 
 final readonly class EmployeeFilter
 {
+    /** @param array<SiteId> $sites */
     public function __construct(
         public ?EstablishmentCode $establishment = null,
-        public ?SiteId $site = null,
+        public array $sites = [],
         public ?ServiceId $service = null,
         public ?\DateTimeInterface $since = null,
     ) {
-        if ($establishment === null && $site === null && $service === null && $since === null) {
+        foreach ($this->sites as $site) {
+            if (! $site instanceof SiteId) {
+                throw new \InvalidArgumentException('Every item in sites array must be an instance of SiteId.');
+            }
+        }
+
+        if ($establishment === null && empty($this->sites) && $service === null && $since === null) {
             throw new \DomainException('EmployeeFilter requires at least one filtering criterion.');
         }
     }
diff --git a/src/Infra/Adapters/Directories/EloquentEmployeeDirectory.php b/src/Infra/Adapters/Directories/EloquentEmployeeDirectory.php
index 9b009a7..456dc70 100644
--- a/src/Infra/Adapters/Directories/EloquentEmployeeDirectory.php
+++ b/src/Infra/Adapters/Directories/EloquentEmployeeDirectory.php
@@ -32,8 +32,9 @@ final class EloquentEmployeeDirectory implements EmployeeDirectory
                 $query->where('establishment', $filter->establishment->value);
             }
 
-            if ($filter->site !== null) {
-                $query->where('site', $filter->site->value);
+            if (! empty($filter->sites)) {
+                $siteValues = array_map(static fn (SiteId $s): string => $s->value, $filter->sites);
+                $query->whereIn('site', $siteValues);
             }
 
             if ($filter->service !== null) {
diff --git a/src/Presentation/Api/V1/Http/Requests/Employees/EmployeesIndexRequest.php b/src/Presentation/Api/V1/Http/Requests/Employees/EmployeesIndexRequest.php
index 6685e1c..cada6bd 100644
--- a/src/Presentation/Api/V1/Http/Requests/Employees/EmployeesIndexRequest.php
+++ b/src/Presentation/Api/V1/Http/Requests/Employees/EmployeesIndexRequest.php
@@ -33,6 +33,8 @@ final class EmployeesIndexRequest extends FormRequest
             'since'         => ['sometimes', 'date'],
             'establishment' => ['sometimes', 'string'],
             'siteId'        => ['sometimes', 'string'],
+            'siteIds'       => ['sometimes', 'array'],
+            'siteIds.*'     => ['sometimes', 'string'],
             'serviceId'     => ['sometimes', 'string'],
         ];
     }
@@ -66,16 +68,29 @@ final class EmployeesIndexRequest extends FormRequest
     {
         $since         = $this->filled('since') ? DatesHelper::parseDateTime($this->string('since')->value()) : null;
         $establishment = $this->filled('establishment') ? new EstablishmentCode($this->string('establishment')->value()) : null;
-        $site          = $this->filled('siteId') ? new SiteId($this->string('siteId')->value()) : null;
         $service       = $this->filled('serviceId') ? new ServiceId($this->string('serviceId')->value()) : null;
 
-        if ($establishment === null && $site === null && $service === null && $since === null) {
+        $sites      = [];
+        $rawSiteIds = $this->input('siteIds');
+        if (is_array($rawSiteIds)) {
+            foreach ($rawSiteIds as $s) {
+                if (is_string($s) && $s !== '') {
+                    $sites[] = new SiteId($s);
+                }
+            }
+        }
+
+        if ($this->filled('siteId')) {
+            $sites[] = new SiteId($this->string('siteId')->value());
+        }
+
+        if ($establishment === null && empty($sites) && $service === null && $since === null) {
             return null;
         }
 
         return new EmployeeFilter(
             establishment: $establishment,
-            site: $site,
+            sites: $sites,
             service: $service,
             since: $since,
         );
diff --git a/tests/Feature/Api/V1/Employee/EmployeesIndexTest.php b/tests/Feature/Api/V1/Employee/EmployeesIndexTest.php
index 2af30a8..c474b67 100644
--- a/tests/Feature/Api/V1/Employee/EmployeesIndexTest.php
+++ b/tests/Feature/Api/V1/Employee/EmployeesIndexTest.php
@@ -116,4 +116,34 @@ describe('Employees Index Feature API', function (): void {
         $response->assertJsonCount(1, 'employees');
         $response->assertJsonPath('employees.0.id', '01155902');
     });
+
+    it('returns 200 OK and filters results for siteIds array query filter', function (): void {
+        // GIVEN
+        Employee::query()->delete();
+
+        Employee::factory()->create([
+            'public_employee_number' => '01155902',
+            'site'                   => 'LDCSER',
+        ]);
+
+        Employee::factory()->create([
+            'public_employee_number' => '01155903',
+            'site'                   => 'SLELA',
+        ]);
+
+        Employee::factory()->create([
+            'public_employee_number' => '01155904',
+            'site'                   => 'OTHER',
+        ]);
+
+        /** @var \Tests\TestCase $test */
+        $test = $this;
+
+        // WHEN
+        $response = $test->getJson('/api/v1/employees?siteIds[]=LDCSER&siteIds[]=SLELA');
+
+        // THEN
+        $response->assertStatus(200);
+        $response->assertJsonCount(2, 'employees');
+    });
 });
diff --git a/tests/Feature/OpenApi/V1/Employee/EmployeeOpenApiTest.php b/tests/Feature/OpenApi/V1/Employee/EmployeeOpenApiTest.php
index 07410be..e00fb22 100644
--- a/tests/Feature/OpenApi/V1/Employee/EmployeeOpenApiTest.php
+++ b/tests/Feature/OpenApi/V1/Employee/EmployeeOpenApiTest.php
@@ -39,6 +39,21 @@ describe('Employee OpenAPI Conformance', function (): void {
         $response->assertValidResponse(200);
     });
 
+    it('validates GET /api/v1/employees list response with siteIds filter against openapi spec', function (): void {
+        // GIVEN
+        /** @var \Tests\TestCase $test */
+        $test = $this;
+
+        // WHEN
+        /** @var \Illuminate\Testing\TestResponse<\Symfony\Component\HttpFoundation\Response> $response */
+        $response = $test->getJson('/api/v1/employees?siteIds[]=LDCSER&siteIds[]=SLELA');
+
+        // THEN
+        $response->assertStatus(200);
+        $response->assertValidRequest();
+        $response->assertValidResponse(200);
+    });
+
     it('validates GET /api/v1/employees/{id} detail response against openapi spec', function (): void {
         // GIVEN
         /** @var \Tests\TestCase $test */
diff --git a/tests/Integration/Infra/Adapters/Directories/EloquentEmployeeDirectoryTest.php b/tests/Integration/Infra/Adapters/Directories/EloquentEmployeeDirectoryTest.php
index d881010..3dd8373 100644
--- a/tests/Integration/Infra/Adapters/Directories/EloquentEmployeeDirectoryTest.php
+++ b/tests/Integration/Infra/Adapters/Directories/EloquentEmployeeDirectoryTest.php
@@ -138,7 +138,7 @@ describe('EloquentEmployeeDirectory Integration Tests', function (): void {
 
         $filter = new EmployeeFilter(
             establishment: new EstablishmentCode('01'),
-            site: new SiteId('LDCSER'),
+            sites: [new SiteId('LDCSER')],
             service: new ServiceId('097'),
             since: new \DateTimeImmutable('2024-01-01 00:00:00')
         );
diff --git a/tests/Unit/Domain/Models/ValueObjects/Employees/EmployeeFilterTest.php b/tests/Unit/Domain/Models/ValueObjects/Employees/EmployeeFilterTest.php
index 6724b9e..24c66db 100644
--- a/tests/Unit/Domain/Models/ValueObjects/Employees/EmployeeFilterTest.php
+++ b/tests/Unit/Domain/Models/ValueObjects/Employees/EmployeeFilterTest.php
@@ -18,6 +18,16 @@ describe('EmployeeFilter Value Object Unit Tests', function (): void {
             ->toThrow(\DomainException::class, 'EmployeeFilter requires at least one filtering criterion.');
     });
 
+    it('throws InvalidArgumentException when sites array contains an item that is not a SiteId', function (): void {
+        // GIVEN
+        $invalidSites = [new SiteId('LDCSER'), 'invalid-string'];
+
+        // WHEN & THEN
+        /** @phpstan-ignore-next-line */
+        expect(fn () => new EmployeeFilter(sites: $invalidSites))
+            ->toThrow(\InvalidArgumentException::class, 'Every item in sites array must be an instance of SiteId.');
+    });
+
     it('instantiates filter with a single parameter', function (): void {
         // GIVEN
         $establishment = new EstablishmentCode('01');
@@ -27,7 +37,7 @@ describe('EmployeeFilter Value Object Unit Tests', function (): void {
 
         // THEN
         expect($filter->establishment)->toBe($establishment)
-            ->and($filter->site)->toBeNull()
+            ->and($filter->sites)->toBeEmpty()
             ->and($filter->service)->toBeNull()
             ->and($filter->since)->toBeNull();
     });
@@ -42,14 +52,14 @@ describe('EmployeeFilter Value Object Unit Tests', function (): void {
         // WHEN
         $filter = new EmployeeFilter(
             establishment: $establishment,
-            site: $site,
+            sites: [$site],
             service: $service,
             since: $since,
         );
 
         // THEN
         expect($filter->establishment)->toBe($establishment)
-            ->and($filter->site)->toBe($site)
+            ->and($filter->sites)->toBe([$site])
             ->and($filter->service)->toBe($service)
             ->and($filter->since)->toBe($since);
     });