diff --git a/src/components/admin/DesignerForm.tsx b/src/components/admin/DesignerForm.tsx
index 05ff35a8..7342563f 100644
--- a/src/components/admin/DesignerForm.tsx
+++ b/src/components/admin/DesignerForm.tsx
@@ -20,7 +20,12 @@ const designerSchema = z.object({
   description: z.string().optional(),
   person_type: z.enum(['company', 'individual', 'firm', 'organization']),
   website_url: z.string().url().optional().or(z.literal('')),
-  founded_year: z.number().min(1800).max(new Date().getFullYear()).optional(),
+  founded_year: z.string()
+    .optional()
+    .transform(val => val === '' || val === undefined ? undefined : Number(val))
+    .refine(val => val === undefined || (!isNaN(val) && val >= 1800 && val <= new Date().getFullYear()), {
+      message: "Founded year must be between 1800 and current year"
+    }),
   headquarters_location: z.string().optional(),
   images: z.object({
     uploaded: z.array(z.object({
@@ -147,7 +152,7 @@ export function DesignerForm({ onSubmit, onCancel, initialData }: DesignerFormPr
                 type="number"
                 min="1800"
                 max={new Date().getFullYear()}
-                {...register('founded_year', { valueAsNumber: true })}
+                {...register('founded_year')}
                 placeholder="e.g. 1972"
               />
               {errors.founded_year && (
diff --git a/src/components/admin/ManufacturerForm.tsx b/src/components/admin/ManufacturerForm.tsx
index c3a4ad36..c685f7e5 100644
--- a/src/components/admin/ManufacturerForm.tsx
+++ b/src/components/admin/ManufacturerForm.tsx
@@ -20,7 +20,12 @@ const manufacturerSchema = z.object({
   description: z.string().optional(),
   person_type: z.enum(['company', 'individual', 'firm', 'organization']),
   website_url: z.string().url().optional().or(z.literal('')),
-  founded_year: z.number().min(1800).max(new Date().getFullYear()).optional(),
+  founded_year: z.string()
+    .optional()
+    .transform(val => val === '' || val === undefined ? undefined : Number(val))
+    .refine(val => val === undefined || (!isNaN(val) && val >= 1800 && val <= new Date().getFullYear()), {
+      message: "Founded year must be between 1800 and current year"
+    }),
   headquarters_location: z.string().optional(),
   images: z.object({
     uploaded: z.array(z.object({
@@ -147,7 +152,7 @@ export function ManufacturerForm({ onSubmit, onCancel, initialData }: Manufactur
                 type="number"
                 min="1800"
                 max={new Date().getFullYear()}
-                {...register('founded_year', { valueAsNumber: true })}
+                {...register('founded_year')}
                 placeholder="e.g. 1972"
               />
               {errors.founded_year && (
diff --git a/src/components/admin/OperatorForm.tsx b/src/components/admin/OperatorForm.tsx
index 246427cf..e3c4fcc5 100644
--- a/src/components/admin/OperatorForm.tsx
+++ b/src/components/admin/OperatorForm.tsx
@@ -20,7 +20,12 @@ const operatorSchema = z.object({
   description: z.string().optional(),
   person_type: z.enum(['company', 'individual', 'firm', 'organization']),
   website_url: z.string().url().optional().or(z.literal('')),
-  founded_year: z.number().min(1800).max(new Date().getFullYear()).optional(),
+  founded_year: z.string()
+    .optional()
+    .transform(val => val === '' || val === undefined ? undefined : Number(val))
+    .refine(val => val === undefined || (!isNaN(val) && val >= 1800 && val <= new Date().getFullYear()), {
+      message: "Founded year must be between 1800 and current year"
+    }),
   headquarters_location: z.string().optional(),
   images: z.object({
     uploaded: z.array(z.object({
@@ -147,7 +152,7 @@ export function OperatorForm({ onSubmit, onCancel, initialData }: OperatorFormPr
                 type="number"
                 min="1800"
                 max={new Date().getFullYear()}
-                {...register('founded_year', { valueAsNumber: true })}
+                {...register('founded_year')}
                 placeholder="e.g. 1972"
               />
               {errors.founded_year && (
diff --git a/src/components/admin/PropertyOwnerForm.tsx b/src/components/admin/PropertyOwnerForm.tsx
index 9a2717c6..38105240 100644
--- a/src/components/admin/PropertyOwnerForm.tsx
+++ b/src/components/admin/PropertyOwnerForm.tsx
@@ -20,7 +20,12 @@ const propertyOwnerSchema = z.object({
   description: z.string().optional(),
   person_type: z.enum(['company', 'individual', 'firm', 'organization']),
   website_url: z.string().url().optional().or(z.literal('')),
-  founded_year: z.number().min(1800).max(new Date().getFullYear()).optional(),
+  founded_year: z.string()
+    .optional()
+    .transform(val => val === '' || val === undefined ? undefined : Number(val))
+    .refine(val => val === undefined || (!isNaN(val) && val >= 1800 && val <= new Date().getFullYear()), {
+      message: "Founded year must be between 1800 and current year"
+    }),
   headquarters_location: z.string().optional(),
   images: z.object({
     uploaded: z.array(z.object({
@@ -147,7 +152,7 @@ export function PropertyOwnerForm({ onSubmit, onCancel, initialData }: PropertyO
                 type="number"
                 min="1800"
                 max={new Date().getFullYear()}
-                {...register('founded_year', { valueAsNumber: true })}
+                {...register('founded_year')}
                 placeholder="e.g. 1972"
               />
               {errors.founded_year && (