diff --git a/EnvelopeGenerator.Application/Common/Dto/PdfSignOptionsDto.cs b/EnvelopeGenerator.Application/Common/Dto/PdfSignOptionsDto.cs
index 70bf3ac5..104e2537 100644
--- a/EnvelopeGenerator.Application/Common/Dto/PdfSignOptionsDto.cs
+++ b/EnvelopeGenerator.Application/Common/Dto/PdfSignOptionsDto.cs
@@ -10,7 +10,7 @@ public sealed record PdfSignOptionsDto
     /// <summary>
     /// 
     /// </summary>
-    public string UUID { get; set; } = null!;
+    public long DocumentElementId { get; set; }
 
     /// <summary>
     /// 
diff --git a/EnvelopeGenerator.Application/Common/Dto/PdfSignatureCheckResultDto.cs b/EnvelopeGenerator.Application/Common/Dto/PdfSignatureCheckResultDto.cs
index 0c5ba02e..7652ca9e 100644
--- a/EnvelopeGenerator.Application/Common/Dto/PdfSignatureCheckResultDto.cs
+++ b/EnvelopeGenerator.Application/Common/Dto/PdfSignatureCheckResultDto.cs
@@ -47,7 +47,7 @@ public sealed record PdfSignatureCheckItemDto(
     string? Filter,
     string? SubFilter,
     string? ApplicationName,
-    string? UUID,
+    long? DocumentElementId,
     string? OriginalDocumentSha256,
     string? MessageDigestHex,
     string? Error);
diff --git a/EnvelopeGenerator.Infrastructure.Crypt/Services/PdfDigitalSignatureService.cs b/EnvelopeGenerator.Infrastructure.Crypt/Services/PdfDigitalSignatureService.cs
index 844fa1e8..e84280f0 100644
--- a/EnvelopeGenerator.Infrastructure.Crypt/Services/PdfDigitalSignatureService.cs
+++ b/EnvelopeGenerator.Infrastructure.Crypt/Services/PdfDigitalSignatureService.cs
@@ -18,7 +18,7 @@ namespace EnvelopeGenerator.Infrastructure.Crypt.Services;
 
 public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options) : IPdfDigitalSignatureService
 {
-    private static readonly Regex SignatureReasonMetaRegex = new(@"\|\s*SFMETA:v1;doc=(?<doc>[0-9a-fA-F-]{36});sha256=(?<sha>[A-Fa-f0-9]{64})$", RegexOptions.CultureInvariant | RegexOptions.Compiled);
+    private static readonly Regex SignatureReasonMetaRegex = new(@"\|\s*SFMETA:v1;deid=(?<deid>\d+);sha256=(?<sha>[A-Fa-f0-9]{64})$", RegexOptions.CultureInvariant | RegexOptions.Compiled);
 
     public async Task SignPdfAsync(Stream inputPdf, Stream outputPdf, PdfSignOptionsDto request, Stream? image = null, CancellationToken cancellationToken = default)
     {
@@ -34,7 +34,7 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
 
             var pkcs11Options = options.Value;
 
-            var reasonWithMeta = BuildReasonWithMeta(request.Reason ?? pkcs11Options.DefaultReason, request.UUID, sourceHashHex);
+            var reasonWithMeta = BuildReasonWithMeta(request.Reason ?? pkcs11Options.DefaultReason, request.DocumentElementId, sourceHashHex);
 
             using var signer = new PdfDocumentSigner(workingInput);
 
@@ -166,7 +166,7 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
                     Filter: signature.Filter,
                     SubFilter: signature.SubFilter,
                     ApplicationName: null,
-                    UUID: reasonMeta.UUID,
+                    DocumentElementId: reasonMeta.DocumentElementId,
                     OriginalDocumentSha256: reasonMeta.OriginalDocumentSha256,
                     MessageDigestHex: TryExtractMessageDigestHex(signature.Contents),
                     Error: null));
@@ -201,7 +201,7 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
                     Filter: signature.Filter,
                     SubFilter: signature.SubFilter,
                     ApplicationName: null,
-                    UUID: reasonMeta.UUID,
+                    DocumentElementId: reasonMeta.DocumentElementId,
                     OriginalDocumentSha256: reasonMeta.OriginalDocumentSha256,
                     MessageDigestHex: null,
                     Error: ex.Message));
@@ -492,11 +492,11 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
         return start + length;
     }
 
-    private static string BuildReasonWithMeta(string? businessReason, string uuid, string sourceHashHex)
+    private static string BuildReasonWithMeta(string? businessReason, long documentElementId, string sourceHashHex)
     {
         var trimmedReason = string.IsNullOrWhiteSpace(businessReason) ? null : businessReason.Trim();
         var prefix = string.IsNullOrWhiteSpace(trimmedReason) ? string.Empty : trimmedReason + " ";
-        return $"{prefix}| SFMETA:v1;doc={uuid};sha256={sourceHashHex}";
+        return $"{prefix}| SFMETA:v1;deid={documentElementId};sha256={sourceHashHex}";
     }
 
     private static string? BuildContactInfo(string? email, string? phone)
@@ -553,7 +553,7 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
             string.IsNullOrWhiteSpace(phone) ? null : phone);
     }
 
-    private static (string? BusinessReason, string? UUID, string? OriginalDocumentSha256) ParseReasonMeta(string? reason)
+    private static (string? BusinessReason, long? DocumentElementId, string? OriginalDocumentSha256) ParseReasonMeta(string? reason)
     {
         if (string.IsNullOrWhiteSpace(reason))
             return (reason, null, null);
@@ -566,9 +566,11 @@ public sealed class PdfDigitalSignatureService(IOptions<Pkcs11Options> options)
         if (string.IsNullOrWhiteSpace(businessReason))
             businessReason = null;
 
+        long? parsedDocumentElementId = long.TryParse(match.Groups["deid"].Value, out var deid) ? deid : null;
+
         return (
             businessReason,
-            match.Groups["doc"].Value,
+            parsedDocumentElementId,
             match.Groups["sha"].Value.ToUpperInvariant());
     }
 }