diff --git a/CHANGELOG.md b/CHANGELOG.md
index e5f285ab..a7c3209c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,14 +6,18 @@
 
 * [PostIt] Une page d'historique des commandes billing permet maintenant d'ouvrir une commande existante.
 * [PostIt] Une vue "Demandes en cours" en lecture seule est disponible pour le performer, filtrée sur les statuts actifs (Inserted, Accepted, InProgress).
+* [Yavsc.Org] Nouvelles entités `Country` et `PerformerCodeInputValidation` pour piloter la validation du code entreprise performer par pays.
 
 ### Changed
 
 * [PostIt] La page détail billing se préremplit depuis une commande existante (Rdv, Brush, MBrush) et passe en mode mise à jour.
+* [Yavsc.Org] Le formulaire `Manage/SetActivity` inclut désormais le pays d'exercice (`fr`, `en`, `pt`) et applique la regex associée au champ `SIREN`.
+* [Yavsc.Org] La vérification externe du numéro d'entreprise est conservée uniquement pour le pays `fr`.
 
 ### Fixed
 
 * [PostIt] Le flux historique n'est plus limité à une simple liste: l'action d'ouverture charge la commande cible puis navigue vers la page détail.
+* [Yavsc.Org] Le champ `SIREN` n'est plus validé avec une règle unique indépendante du pays d'exercice.
 
 ## [1.0.8-rc9] - unstable
 
diff --git a/src/Yavsc.Abstract/Workflow/Country.cs b/src/Yavsc.Abstract/Workflow/Country.cs
new file mode 100644
index 00000000..d782d0aa
--- /dev/null
+++ b/src/Yavsc.Abstract/Workflow/Country.cs
@@ -0,0 +1,19 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace Yavsc.Models.Workflow
+{
+    /// <summary>
+    /// Supported country of exercise for performer profile validations.
+    /// </summary>
+    public class Country
+    {
+        [Key]
+        [MaxLength(2)]
+        [MinLength(2)]
+        public string Code { get; set; } = string.Empty;
+
+        [Required]
+        [MaxLength(64)]
+        public string DisplayName { get; set; } = string.Empty;
+    }
+}
\ No newline at end of file
diff --git a/src/Yavsc.Abstract/Workflow/IPerformerProfile.cs b/src/Yavsc.Abstract/Workflow/IPerformerProfile.cs
index e53583a5..4314dd37 100644
--- a/src/Yavsc.Abstract/Workflow/IPerformerProfile.cs
+++ b/src/Yavsc.Abstract/Workflow/IPerformerProfile.cs
@@ -3,6 +3,7 @@ namespace Yavsc.Workflow
     public interface IPerformerProfile
     {
         string PerformerId { get; set; }
+        string ExerciseCountryCode { get; set; }
         string SIREN { get; set; }
         bool AcceptNotifications { get; set; }
         long OrganizationAddressId { get; set; }
diff --git a/src/Yavsc.Abstract/Workflow/PerformerCodeInputValidation.cs b/src/Yavsc.Abstract/Workflow/PerformerCodeInputValidation.cs
new file mode 100644
index 00000000..84e9c1cc
--- /dev/null
+++ b/src/Yavsc.Abstract/Workflow/PerformerCodeInputValidation.cs
@@ -0,0 +1,86 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+
+namespace Yavsc.Models.Workflow
+{
+    /// <summary>
+    /// Validation rule for performer business code input by country.
+    /// </summary>
+    public class PerformerCodeInputValidation
+    {
+        [Key]
+        public long Id { get; set; }
+
+        [Required]
+        [MaxLength(2)]
+        [MinLength(2)]
+        public string CountryCode { get; set; } = string.Empty;
+
+        [Required]
+        [MaxLength(256)]
+        public string RegularExpression { get; set; } = string.Empty;
+
+        [Required]
+        [MaxLength(128)]
+        public string ErrorMessage { get; set; } = string.Empty;
+
+        [ForeignKey(nameof(CountryCode))]
+        public Country Country { get; set; }
+    }
+
+    public static class PerformerCodeInputValidationCatalog
+    {
+        public static readonly IReadOnlyList<Country> Countries = new List<Country>
+        {
+            new() { Code = "fr", DisplayName = "France" },
+            new() { Code = "en", DisplayName = "England" },
+            new() { Code = "pt", DisplayName = "Portugal" },
+        };
+
+        public static readonly IReadOnlyList<PerformerCodeInputValidation> Rules = new List<PerformerCodeInputValidation>
+        {
+            new()
+            {
+                Id = 1,
+                CountryCode = "fr",
+                RegularExpression = "^[0-9]{9,14}$",
+                ErrorMessage = "Le code FR doit contenir entre 9 et 14 chiffres."
+            },
+            new()
+            {
+                Id = 2,
+                CountryCode = "en",
+                RegularExpression = "^[A-Za-z0-9]{8,14}$",
+                ErrorMessage = "Le code EN doit contenir entre 8 et 14 caracteres alphanumeriques."
+            },
+            new()
+            {
+                Id = 3,
+                CountryCode = "pt",
+                RegularExpression = "^[0-9]{9}$",
+                ErrorMessage = "Le code PT doit contenir exactement 9 chiffres."
+            },
+        };
+
+        public static string NormalizeCountryCode(string? countryCode)
+        {
+            return (countryCode ?? string.Empty).Trim().ToLowerInvariant();
+        }
+
+        public static PerformerCodeInputValidation? GetRule(string? countryCode)
+        {
+            var normalized = NormalizeCountryCode(countryCode);
+            foreach (var rule in Rules)
+            {
+                if (string.Equals(rule.CountryCode, normalized, StringComparison.Ordinal))
+                {
+                    return rule;
+                }
+            }
+
+            return null;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Yavsc.Org.Tests/NonRegression/PerformerCodeInputValidationTests.cs b/src/Yavsc.Org.Tests/NonRegression/PerformerCodeInputValidationTests.cs
new file mode 100644
index 00000000..c47bdff5
--- /dev/null
+++ b/src/Yavsc.Org.Tests/NonRegression/PerformerCodeInputValidationTests.cs
@@ -0,0 +1,76 @@
+using System.ComponentModel.DataAnnotations;
+using Yavsc.Models.Relationship;
+using Yavsc.Models.Workflow;
+
+namespace Yavsc.Tests.NonRegression;
+
+public class PerformerCodeInputValidationTests
+{
+    [Fact]
+    public void Validate_rejects_unknown_country_code()
+    {
+        var profile = CreateBaseProfile();
+        profile.ExerciseCountryCode = "de";
+        profile.SIREN = "123456789";
+
+        var results = Validate(profile);
+
+        Assert.Contains(results, r => r.MemberNames.Contains(nameof(PerformerProfile.ExerciseCountryCode)));
+    }
+
+    [Fact]
+    public void Validate_rejects_code_not_matching_country_rule()
+    {
+        var profile = CreateBaseProfile();
+        profile.ExerciseCountryCode = "pt";
+        profile.SIREN = "ABC123";
+
+        var results = Validate(profile);
+
+        Assert.Contains(results, r => r.MemberNames.Contains(nameof(PerformerProfile.SIREN)));
+    }
+
+    [Fact]
+    public void Validate_accepts_country_specific_valid_codes()
+    {
+        var fr = CreateBaseProfile();
+        fr.ExerciseCountryCode = "fr";
+        fr.SIREN = "123456789";
+
+        var en = CreateBaseProfile();
+        en.ExerciseCountryCode = "en";
+        en.SIREN = "AB12CD34";
+
+        var pt = CreateBaseProfile();
+        pt.ExerciseCountryCode = "pt";
+        pt.SIREN = "501964843";
+
+        Assert.Empty(Validate(fr));
+        Assert.Empty(Validate(en));
+        Assert.Empty(Validate(pt));
+    }
+
+    private static PerformerProfile CreateBaseProfile()
+    {
+        return new PerformerProfile
+        {
+            PerformerId = "perf-1",
+            SIREN = "123456789",
+            ExerciseCountryCode = "fr",
+            OrganizationAddress = new Location
+            {
+                Address = "1 rue du Test",
+                Latitude = 48.8566,
+                Longitude = 2.3522,
+            },
+        };
+    }
+
+    private static List<ValidationResult> Validate(PerformerProfile profile)
+    {
+        var ctx = new ValidationContext(profile);
+        var results = new List<ValidationResult>();
+        Validator.TryValidateObject(profile, ctx, results, validateAllProperties: true);
+        return results;
+    }
+}
\ No newline at end of file
diff --git a/src/Yavsc.Org/Controllers/Accounting/ManageController.cs b/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
index 43e11cd2..2c8cbec9 100644
--- a/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
+++ b/src/Yavsc.Org/Controllers/Accounting/ManageController.cs
@@ -5,6 +5,7 @@ using Microsoft.AspNetCore.Mvc;
 using Microsoft.Extensions.Localization;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Options;
+using Microsoft.AspNetCore.Mvc.Rendering;
 using Yavsc.Models.Workflow;
 using Yavsc.Helpers;
 using Yavsc.Models.Relationship;
@@ -544,15 +545,19 @@ namespace Yavsc.Controllers
             {
                 var currentProfile = _dbContext.Performers.Include(x => x.OrganizationAddress)
                 .First(x => x.PerformerId == uid);
+                currentProfile.ExerciseCountryCode = NormalizeCountryCodeOrDefault(currentProfile.ExerciseCountryCode);
                 ViewBag.Activities = _dbContext.ActivityItems(existing.Activity);
+                SetExerciseCountries(currentProfile.ExerciseCountryCode);
                 return View(currentProfile);
             }
 
             ViewBag.Activities = _dbContext.ActivityItems(new List<UserActivity>());
+            SetExerciseCountries("fr");
             return View(new PerformerProfile
             {
                 PerformerId = user.Id,
                 Performer = user,
+                ExerciseCountryCode = "fr",
                 OrganizationAddress = new Location()
             });
         }
@@ -563,28 +568,32 @@ namespace Yavsc.Controllers
         {
             var user = GetCurrentUserAsync().Result;
             var uid = user.Id;
+            model.ExerciseCountryCode = NormalizeCountryCodeOrDefault(model.ExerciseCountryCode);
             try
             {
                 if (ModelState.IsValid)
                 {
-
-                    var exSiren = await _dbContext.ExceptionsSIREN.FirstOrDefaultAsync(
-                        ex => ex.SIREN == model.SIREN
-                    );
-                    if (exSiren != null)
+                    var isFrenchPerformerCode = string.Equals(model.ExerciseCountryCode, "fr", StringComparison.Ordinal);
+                    if (isFrenchPerformerCode)
                     {
-                        _logger.LogInformation("Exception SIREN:" + exSiren);
-                    }
-                    else
-                    {
-                        var taskCheck = await _cchecker.CheckAsync(model.SIREN);
-                        if (!taskCheck.success)
+                        var exSiren = await _dbContext.ExceptionsSIREN.FirstOrDefaultAsync(
+                            ex => ex.SIREN == model.SIREN
+                        );
+                        if (exSiren != null)
                         {
-                            ModelState.AddModelError(
-                                "SIREN",
-                                _SR["Invalid company number"] + " (" + taskCheck.errorCode + ")"
-                            );
-                            _logger.LogInformation($"Invalid company number: {model.SIREN}/{taskCheck.errorType}/{taskCheck.errorCode}/{taskCheck.errorMessage}" );
+                            _logger.LogInformation("Exception SIREN:" + exSiren);
+                        }
+                        else
+                        {
+                            var taskCheck = await _cchecker.CheckAsync(model.SIREN);
+                            if (!taskCheck.success)
+                            {
+                                ModelState.AddModelError(
+                                    "SIREN",
+                                    _SR["Invalid company number"] + " (" + taskCheck.errorCode + ")"
+                                );
+                                _logger.LogInformation($"Invalid company number: {model.SIREN}/{taskCheck.errorType}/{taskCheck.errorCode}/{taskCheck.errorMessage}" );
+                            }
                         }
                     }
                 }
@@ -622,10 +631,32 @@ namespace Yavsc.Controllers
             }
             ViewBag.Activities = _dbContext.ActivityItems(new List<UserActivity>());
             ViewBag.GoogleSettings = _googleSettings;
+            SetExerciseCountries(model.ExerciseCountryCode);
             model.Performer = _dbContext.Users.Single(u=>u.Id == model.PerformerId);
             return View(model);
         }
 
+        private static string NormalizeCountryCodeOrDefault(string? code)
+        {
+            var normalized = PerformerCodeInputValidationCatalog.NormalizeCountryCode(code);
+            if (string.IsNullOrWhiteSpace(normalized))
+            {
+                return "fr";
+            }
+
+            return normalized;
+        }
+
+        private void SetExerciseCountries(string? selectedCountryCode)
+        {
+            var selected = NormalizeCountryCodeOrDefault(selectedCountryCode);
+            ViewBag.ExerciseCountries = new SelectList(
+                PerformerCodeInputValidationCatalog.Countries,
+                nameof(Country.Code),
+                nameof(Country.DisplayName),
+                selected);
+        }
+
         [HttpPost]
         public async Task<IActionResult> UnsetActivity()
         {
diff --git a/src/Yavsc.Org/Views/Manage/SetActivity.cshtml b/src/Yavsc.Org/Views/Manage/SetActivity.cshtml
index b319faf4..d9d2e0ae 100644
--- a/src/Yavsc.Org/Views/Manage/SetActivity.cshtml
+++ b/src/Yavsc.Org/Views/Manage/SetActivity.cshtml
@@ -67,6 +67,15 @@
             <span asp-validation-for="Active" class="text-danger"></span>
         </div>
     </div>
+    <div class="form-group">
+
+        <label asp-for="ExerciseCountryCode" class="col-md-2 control-label">Pays d'exercice</label>
+        <div class="col-md-10">
+            <select asp-for="ExerciseCountryCode" asp-items="ViewBag.ExerciseCountries" class="form-control"></select>
+
+            <span asp-validation-for="ExerciseCountryCode" class="text-danger"></span>
+        </div>
+    </div>
     <div class="form-group">
 
         <label asp-for="SIREN" class="col-md-2 control-label">SIREN</label>
diff --git a/src/Yavsc.Server/Models/ApplicationDbContext.cs b/src/Yavsc.Server/Models/ApplicationDbContext.cs
index 7bb5ed18..cb08023a 100644
--- a/src/Yavsc.Server/Models/ApplicationDbContext.cs
+++ b/src/Yavsc.Server/Models/ApplicationDbContext.cs
@@ -109,6 +109,21 @@ namespace Yavsc.Models
 
             builder.Entity<Activity>().Property(a => a.ParentCode).IsRequired(false);
 
+            builder.Entity<Country>().HasKey(c => c.Code);
+            builder.Entity<PerformerCodeInputValidation>()
+                .HasOne(v => v.Country)
+                .WithMany()
+                .HasForeignKey(v => v.CountryCode)
+                .OnDelete(DeleteBehavior.Restrict);
+
+            builder.Entity<Country>().HasData(
+                PerformerCodeInputValidationCatalog.Countries
+            );
+
+            builder.Entity<PerformerCodeInputValidation>().HasData(
+                PerformerCodeInputValidationCatalog.Rules
+            );
+
             builder.Entity<Client>().Property("Id").UseIdentityAlwaysColumn();
             builder.Entity<ClientSecret>().Property("Id").UseIdentityAlwaysColumn();
             builder.Entity<ClientScope>().Property("Id").UseIdentityAlwaysColumn();
@@ -262,6 +277,8 @@ namespace Yavsc.Models
 
         public DbSet<HairMultiCutQuery> HairMultiCutQueries { get; set; }
         public DbSet<PerformerProfile> Performers { get; set; }
+        public DbSet<Country> Countries { get; set; }
+        public DbSet<PerformerCodeInputValidation> PerformerCodeInputValidations { get; set; }
 
         public DbSet<Estimate> Estimates { get; set; }
         public DbSet<Signature> Signatures { get; set; }
diff --git a/src/Yavsc.Server/Models/Workflow/PerformerProfile.cs b/src/Yavsc.Server/Models/Workflow/PerformerProfile.cs
index 7067bc13..80622ac8 100644
--- a/src/Yavsc.Server/Models/Workflow/PerformerProfile.cs
+++ b/src/Yavsc.Server/Models/Workflow/PerformerProfile.cs
@@ -4,12 +4,14 @@ using System.ComponentModel.DataAnnotations.Schema;
 namespace Yavsc.Models.Workflow
 {
     using System;
+    using System.Collections.Generic;
+    using System.Text.RegularExpressions;
     using Models.Relationship;
     using Newtonsoft.Json;
     using Yavsc.Attributes.Validation;
     using Yavsc.Workflow;
 
-    public class PerformerProfile : IPerformerProfile {
+    public class PerformerProfile : IPerformerProfile, IValidatableObject {
 
         [Key]
         public string PerformerId { get; set; }
@@ -20,8 +22,11 @@ namespace Yavsc.Models.Workflow
         [Display(Name="Activity"), JsonIgnore]
         public virtual List<UserActivity> Activity { get; set; }
 
-        [Required,YaStringLength(14),Display(Name="SIREN"),
-        RegularExpression(@"^[0-9]{9,14}$", ErrorMessage = "Only numbers are allowed here")]
+        [Required, Display(Name = "Country of exercise")]
+        [MinLength(2), MaxLength(2)]
+        public string ExerciseCountryCode { get; set; } = "fr";
+
+        [Required,YaStringLength(14),Display(Name="SIREN")]
         public string SIREN { get; set; }
 
         public long OrganizationAddressId { get; set; }
@@ -60,5 +65,40 @@ namespace Yavsc.Models.Workflow
             return Performer?.Posts?.Count > 0 ;
         } }
 
+        public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
+        {
+            var countryCode = PerformerCodeInputValidationCatalog.NormalizeCountryCode(ExerciseCountryCode);
+
+            if (string.IsNullOrWhiteSpace(countryCode))
+            {
+                yield return new ValidationResult(
+                    "Le pays d'exercice est requis.",
+                    new[] { nameof(ExerciseCountryCode) });
+                yield break;
+            }
+
+            var rule = PerformerCodeInputValidationCatalog.GetRule(countryCode);
+            if (rule is null)
+            {
+                yield return new ValidationResult(
+                    "Le pays d'exercice doit etre l'un des suivants: fr, en, pt.",
+                    new[] { nameof(ExerciseCountryCode) });
+                yield break;
+            }
+
+            if (string.IsNullOrWhiteSpace(SIREN))
+            {
+                yield break;
+            }
+
+            var normalizedCode = SIREN.Trim();
+            if (!Regex.IsMatch(normalizedCode, rule.RegularExpression, RegexOptions.CultureInvariant))
+            {
+                yield return new ValidationResult(
+                    rule.ErrorMessage,
+                    new[] { nameof(SIREN) });
+            }
+        }
+
     }
 }