diff --git a/src/ert/config/analysis_config.py b/src/ert/config/analysis_config.py
index b14cc3968e6..a2afdf9ad6f 100644
--- a/src/ert/config/analysis_config.py
+++ b/src/ert/config/analysis_config.py
@@ -10,20 +10,19 @@
 from pydantic import ValidationError
 
 from .analysis_module import ESSettings, IESSettings
+from .design_matrix import DesignMatrix
 from .parsing import (
     AnalysisMode,
     ConfigDict,
     ConfigKeys,
     ConfigValidationError,
     ConfigWarning,
-    ErrorInfo,
 )
 
 logger = logging.getLogger(__name__)
 
 DEFAULT_ANALYSIS_MODE = AnalysisMode.ENSEMBLE_SMOOTHER
 ObservationGroups = List[str]
-from ._option_dict import option_dict
 
 
 @dataclass
@@ -33,47 +32,6 @@ class UpdateSettings:
     auto_scale_observations: List[ObservationGroups] = field(default_factory=list)
 
 
-@dataclass
-class DesignMatrixArgs:
-    xls_filename: Path
-    designsheet: str
-    defaultsheet: str
-
-    @classmethod
-    def from_config_list(cls, config_list: List[str]) -> "DesignMatrixArgs":
-        filename = Path(config_list[0])
-        options = option_dict(config_list, 1)
-        design_sheet = options.get("DESIGN_SHEET")
-        default_sheet = options.get("DEFAULT_SHEET")
-        errors = []
-        if filename.suffix not in {
-            ".xlsx",
-            ".xls",
-        }:
-            errors.append(
-                ErrorInfo(
-                    f"DESIGN_MATRIX must be of format .xls or .xslx; is {filename}"
-                ).set_context(config_list)
-            )
-        if design_sheet is None:
-            errors.append(
-                ErrorInfo("Missing required DESIGN_SHEET").set_context(config_list)
-            )
-        if default_sheet is None:
-            errors.append(
-                ErrorInfo("Missing required DEFAULT_SHEET").set_context(config_list)
-            )
-        if errors:
-            raise ConfigValidationError.from_collected(errors)
-        assert design_sheet is not None
-        assert default_sheet is not None
-        return cls(
-            xls_filename=filename,
-            designsheet=design_sheet,
-            defaultsheet=default_sheet,
-        )
-
-
 @dataclass
 class AnalysisConfig:
     max_runtime: Optional[int] = None
@@ -83,7 +41,7 @@ class AnalysisConfig:
     ies_module: IESSettings = field(default_factory=IESSettings)
     observation_settings: UpdateSettings = field(default_factory=UpdateSettings)
     num_iterations: int = 1
-    design_matrix_args: Optional[DesignMatrixArgs] = None
+    design_matrix_args: Optional[DesignMatrix] = None
 
     @no_type_check
     @classmethod
@@ -236,9 +194,7 @@ def from_dict(cls, config_dict: ConfigDict) -> "AnalysisConfig":
             observation_settings=obs_settings,
             es_module=es_settings,
             ies_module=ies_settings,
-            design_matrix_args=DesignMatrixArgs.from_config_list(
-                design_matrix_config_list
-            )
+            design_matrix_args=DesignMatrix.from_config_list(design_matrix_config_list)
             if design_matrix_config_list is not None
             else None,
         )
diff --git a/src/ert/config/design_matrix.py b/src/ert/config/design_matrix.py
new file mode 100644
index 00000000000..2760f42c415
--- /dev/null
+++ b/src/ert/config/design_matrix.py
@@ -0,0 +1,52 @@
+from __future__ import annotations
+
+from dataclasses import dataclass
+from pathlib import Path
+from typing import List
+
+from ._option_dict import option_dict
+from .parsing import (
+    ConfigValidationError,
+    ErrorInfo,
+)
+
+
+@dataclass
+class DesignMatrix:
+    xls_filename: Path
+    designsheet: str
+    defaultsheet: str
+
+    @classmethod
+    def from_config_list(cls, config_list: List[str]) -> "DesignMatrix":
+        filename = Path(config_list[0])
+        options = option_dict(config_list, 1)
+        design_sheet = options.get("DESIGN_SHEET")
+        default_sheet = options.get("DEFAULT_SHEET")
+        errors = []
+        if filename.suffix not in {
+            ".xlsx",
+            ".xls",
+        }:
+            errors.append(
+                ErrorInfo(
+                    f"DESIGN_MATRIX must be of format .xls or .xslx; is {filename}"
+                ).set_context(config_list)
+            )
+        if design_sheet is None:
+            errors.append(
+                ErrorInfo("Missing required DESIGN_SHEET").set_context(config_list)
+            )
+        if default_sheet is None:
+            errors.append(
+                ErrorInfo("Missing required DEFAULT_SHEET").set_context(config_list)
+            )
+        if errors:
+            raise ConfigValidationError.from_collected(errors)
+        assert design_sheet is not None
+        assert default_sheet is not None
+        return cls(
+            xls_filename=filename,
+            designsheet=design_sheet,
+            defaultsheet=default_sheet,
+        )