diff --git a/DocumentOperator.API/Controllers/PdfAttachmentController.cs b/DocumentOperator.API/Controllers/PdfAttachmentController.cs
index ad20e36..10c3efb 100644
--- a/DocumentOperator.API/Controllers/PdfAttachmentController.cs
+++ b/DocumentOperator.API/Controllers/PdfAttachmentController.cs
@@ -2,6 +2,7 @@ using DocumentService.Application.AddAttachments;
 using DocumentService.Application.CheckPdfAttachments.Queries;
 using DocumentService.Application.Common.DTOs;
 using DocumentService.Application.ExtractPdfAttachments;
+using DocumentService.Client.Models.Requests;
 using DocumentService.Domain.Common.Exceptions;
 using MediatR;
 using Microsoft.AspNetCore.Http;
diff --git a/DocumentOperator.API/Controllers/PdfConversionController.cs b/DocumentOperator.API/Controllers/PdfConversionController.cs
index e394c37..9bf7228 100644
--- a/DocumentOperator.API/Controllers/PdfConversionController.cs
+++ b/DocumentOperator.API/Controllers/PdfConversionController.cs
@@ -1,5 +1,6 @@
 using DocumentService.Application.ConvertFromPdfA;
 using DocumentService.Application.ConvertToPdfA;
+using DocumentService.Client.Models.Requests;
 using DocumentService.Domain.Common.Exceptions;
 using MediatR;
 using Microsoft.AspNetCore.Http;
@@ -179,33 +180,3 @@ public class PdfConversionController(IMediator mediator) : ControllerBase
         return File(resultPdf, "application/pdf", "converted-pdf.pdf");
     }
 }
-
-/// <summary>
-/// Request DTO for converting PDF to PDF/A
-/// </summary>
-public record ConvertToPdfARequest
-{
-    /// <summary>
-    /// PDF document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public required string Base64Pdf { get; init; }
-
-    /// <summary>
-    /// Target PDF/A level (default: "PDF/A-3b")
-    /// </summary>
-    /// <example>PDF/A-3b</example>
-    public string? PdfALevel { get; init; }
-}
-
-/// <summary>
-/// Request DTO for converting PDF/A to PDF
-/// </summary>
-public record ConvertFromPdfARequest
-{
-    /// <summary>
-    /// PDF/A document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public required string Base64Pdf { get; init; }
-}
diff --git a/DocumentOperator.API/Controllers/PdfValidationController.cs b/DocumentOperator.API/Controllers/PdfValidationController.cs
index e54feea..7d587d4 100644
--- a/DocumentOperator.API/Controllers/PdfValidationController.cs
+++ b/DocumentOperator.API/Controllers/PdfValidationController.cs
@@ -1,6 +1,7 @@
 using DocumentService.Application.Common.DTOs;
 using DocumentService.Application.ValidatePdf.Queries;
 using DocumentService.Application.ValidatePdfA.Queries;
+using DocumentService.Client.Models.Requests;
 using DocumentService.Domain.Common.Exceptions;
 using MediatR;
 using Microsoft.AspNetCore.Mvc;
@@ -167,27 +168,3 @@ public class PdfValidationController(IMediator Mediator) : ControllerBase
         return Ok(result);
     }
 }
-
-/// <summary>
-/// Request DTO for Base64-encoded PDF validation
-/// </summary>
-public record ValidatePdfBase64Request
-{
-    /// <summary>
-    /// PDF document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public string Base64Pdf { get; init; } = string.Empty;
-}
-
-/// <summary>
-/// Request DTO for Base64-encoded PDF/A validation
-/// </summary>
-public record ValidatePdfABase64Request
-{
-    /// <summary>
-    /// PDF document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public string Base64Pdf { get; init; } = string.Empty;
-}
diff --git a/DocumentOperator.API/Controllers/ZugferdController.cs b/DocumentOperator.API/Controllers/ZugferdController.cs
index f44e908..3967f51 100644
--- a/DocumentOperator.API/Controllers/ZugferdController.cs
+++ b/DocumentOperator.API/Controllers/ZugferdController.cs
@@ -1,6 +1,7 @@
 using DocumentService.Application.Common.DTOs;
 using DocumentService.Application.ExtractZugferd;
 using DocumentService.Application.HasZugferd.Queries;
+using DocumentService.Client.Models.Requests;
 using DocumentService.Domain.Common.Exceptions;
 using MediatR;
 using Microsoft.AspNetCore.Http;
@@ -176,27 +177,3 @@ public class ZugferdController(IMediator mediator) : ControllerBase
         return Ok(result);
     }
 }
-
-/// <summary>
-/// Request DTO for Base64-encoded PDF ZUGFeRD check
-/// </summary>
-public record HasZugferdRequest
-{
-    /// <summary>
-    /// PDF document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public string Base64Pdf { get; init; } = string.Empty;
-}
-
-/// <summary>
-/// Request DTO for Base64-encoded PDF ZUGFeRD extraction
-/// </summary>
-public record ExtractZugferdRequest
-{
-    /// <summary>
-    /// PDF document encoded as Base64 string
-    /// </summary>
-    /// <example>JVBERi0xLjQKJeLjz9MKMSAwIG9iago8PC9UeXBlL0NhdGFsb2c...</example>
-    public required string Base64Pdf { get; init; }
-}