diff --git a/CertReports.Syncfusion/Program.cs b/CertReports.Syncfusion/Program.cs
index 556622b..2fab149 100644
--- a/CertReports.Syncfusion/Program.cs
+++ b/CertReports.Syncfusion/Program.cs
@@ -35,6 +35,7 @@ builder.Services.AddHealthChecks()
 builder.Services.AddScoped<ICertificateDataService, CertificateDataService>();
 builder.Services.AddScoped<IChartDataService, ChartDataService>();
 builder.Services.AddScoped<IChartDataServiceV2, ChartDataServiceV2>();
+builder.Services.AddScoped<IUnderlyingChartDataService, UnderlyingChartDataService>();
 builder.Services.AddScoped<IPdfSectionRenderer, AnagraficaSectionRenderer>();
 builder.Services.AddScoped<IPdfSectionRenderer, EventiSectionRenderer>();
 builder.Services.AddScoped<IPdfSectionRenderer, ScenarioSectionRenderer>();
diff --git a/CertReports.Syncfusion/Services/Implementations/UnderlyingChartDataService.cs b/CertReports.Syncfusion/Services/Implementations/UnderlyingChartDataService.cs
new file mode 100644
index 0000000..7a3c8b1
--- /dev/null
+++ b/CertReports.Syncfusion/Services/Implementations/UnderlyingChartDataService.cs
@@ -0,0 +1,72 @@
+using CertReports.Syncfusion.Models;
+using Microsoft.Data.SqlClient;
+using System.Data;
+
+namespace CertReports.Syncfusion.Services.Implementations;
+
+/// <summary>
+/// Recupera i dati per il grafico standalone di un singolo sottostante
+/// (nessun contesto certificato). SP utilizzata: cedlab_Chart_UnderlyingOnly.
+/// </summary>
+public interface IUnderlyingChartDataService
+{
+    Task<UnderlyingChartData?> GetChartDataAsync(int idUnderlyings);
+}
+
+public class UnderlyingChartDataService : IUnderlyingChartDataService
+{
+    private readonly string _connectionString;
+    private readonly ILogger<UnderlyingChartDataService> _logger;
+
+    public UnderlyingChartDataService(IConfiguration config, ILogger<UnderlyingChartDataService> logger)
+    {
+        _connectionString = config.GetConnectionString("CertDb")
+            ?? throw new InvalidOperationException("ConnectionString 'CertDb' non configurata.");
+        _logger = logger;
+    }
+
+    public async Task<UnderlyingChartData?> GetChartDataAsync(int idUnderlyings)
+    {
+        await using var conn = new SqlConnection(_connectionString);
+        await conn.OpenAsync();
+
+        await using var cmd = new SqlCommand("cedlab_Chart_UnderlyingOnly", conn)
+            { CommandType = CommandType.StoredProcedure };
+        cmd.Parameters.AddWithValue("@IDUnderlyings", idUnderlyings);
+
+        var result = new UnderlyingChartData { IDUnderlyings = idUnderlyings };
+
+        await using var r = await cmd.ExecuteReaderAsync();
+        while (await r.ReadAsync())
+        {
+            if (result.Points.Count == 0)
+                result.Nome = ToStr(r, "Nome");
+
+            result.Points.Add(new UnderlyingChartPoint
+            {
+                Date = r.GetDateTime(r.GetOrdinal("Px_date")),
+                Px   = Convert.ToDecimal(r.GetValue(r.GetOrdinal("Px"))),
+            });
+        }
+
+        if (result.Points.Count == 0)
+        {
+            _logger.LogWarning(
+                "Nessun prezzo trovato per il sottostante {IDUnderlyings} (non trovato, cancellato, sospeso, o senza storico prezzi)",
+                idUnderlyings);
+            return null;
+        }
+
+        _logger.LogInformation(
+            "Dati grafico sottostante caricati per {IDUnderlyings}: {Points} punti",
+            idUnderlyings, result.Points.Count);
+
+        return result;
+    }
+
+    private static string ToStr(SqlDataReader r, string column)
+    {
+        int ord = r.GetOrdinal(column);
+        return r.IsDBNull(ord) ? string.Empty : r.GetString(ord);
+    }
+}