diff --git a/src/SimpleDTO.php b/src/SimpleDTO.php
index fc65cb4..fb8431b 100644
--- a/src/SimpleDTO.php
+++ b/src/SimpleDTO.php
@@ -33,7 +33,8 @@ abstract class SimpleDTO implements BaseDTO, CastsAttributes
 {
     use DataResolver, DataTransformer;
 
-    protected array $data = [];
+    /** @internal */
+    protected array $dtoData = [];
 
     protected array $validatedData = [];
 
@@ -63,7 +64,7 @@ public function __construct(?array $data = null)
         }
 
         $this->buildAttributesData();
-        $this->data = $this->buildDataForValidation($data);
+        $this->dtoData = $this->buildDataForValidation($data);
 
         $this->initConfig();
 
@@ -193,7 +194,7 @@ protected function passedValidation(): void
             }
         }
 
-        $this->data = [];
+        $this->dtoData = [];
     }
 
     protected function failedValidation(): void
@@ -219,7 +220,7 @@ protected function validatedData(): array
         /** @var array<Castable> $casts */
         $casts = $this->buildCasts();
 
-        foreach ($this->data as $key => $value) {
+        foreach ($this->dtoData as $key => $value) {
             if (in_array($key, $acceptedKeys)) {
                 if (! array_key_exists($key, $casts)) {
                     if ($this->requireCasting) {
@@ -514,7 +515,7 @@ private function getAcceptedProperties(): array
     private function isforbiddenProperty(string $property): bool
     {
         return in_array($property, [
-            'data',
+            'dtoData',
             'validatedData',
             'requireCasting',
             'validator',
diff --git a/src/ValidatedDTO.php b/src/ValidatedDTO.php
index 0efab0c..983e84f 100644
--- a/src/ValidatedDTO.php
+++ b/src/ValidatedDTO.php
@@ -51,7 +51,7 @@ protected function validatedData(): array
         /** @var array<Castable> $casts */
         $casts = $this->buildCasts();
 
-        foreach ($this->data as $key => $value) {
+        foreach ($this->dtoData as $key => $value) {
             if (in_array($key, $acceptedKeys)) {
                 if (! array_key_exists($key, $casts)) {
                     if ($this->requireCasting) {
@@ -83,7 +83,7 @@ protected function validatedData(): array
     protected function isValidData(): bool
     {
         $this->validator = Validator::make(
-            $this->data,
+            $this->dtoData,
             $this->rulesList(),
             $this->messagesList(),
             $this->attributes()