diff --git a/src/Geopilot.Api/ContextExtensions.cs b/src/Geopilot.Api/ContextExtensions.cs
index c427502e..51b15d88 100644
--- a/src/Geopilot.Api/ContextExtensions.cs
+++ b/src/Geopilot.Api/ContextExtensions.cs
@@ -119,7 +119,7 @@ public static void SeedMandates(this Context context)
             .RuleFor(o => o.Name, f => f.Commerce.ProductName())
             .RuleFor(o => o.FileTypes, f => f.PickRandom(knownFileFormats, 4).Distinct().ToArray())
             .RuleFor(o => o.EvaluatePrecursorDelivery, f => f.PickRandom<FieldEvaluationType>())
-            .RuleFor(o => o.EvaluatePartial, f => f.PickRandom<FieldEvaluationType>())
+            .RuleFor(o => o.EvaluatePartial, f => f.PickRandom(FieldEvaluationType.NotEvaluated, FieldEvaluationType.Required))
             .RuleFor(o => o.EvaluateComment, f => f.PickRandom<FieldEvaluationType>())
             .RuleFor(o => o.SpatialExtent, f => GetExtent())
             .Ignore(o => o.Coordinates)
diff --git a/src/Geopilot.Api/Models/Mandate.cs b/src/Geopilot.Api/Models/Mandate.cs
index b4d3cc03..5a1cbfcb 100644
--- a/src/Geopilot.Api/Models/Mandate.cs
+++ b/src/Geopilot.Api/Models/Mandate.cs
@@ -1,4 +1,5 @@
 using NetTopologySuite.Geometries;
+using System.ComponentModel.DataAnnotations;
 using System.ComponentModel.DataAnnotations.Schema;
 using System.Text.Json.Serialization;
 
@@ -50,6 +51,7 @@ public class Mandate
     /// Defines how <see cref="Delivery.Partial"/> is evaluated.
     /// </summary>
     [Column(TypeName = "varchar(12)")]
+    [AllowedValues(FieldEvaluationType.NotEvaluated, FieldEvaluationType.Required)]
     public FieldEvaluationType EvaluatePartial { get; set; }
 
     /// <summary>