diff --git a/website/openapi_v2.en.yaml b/website/openapi_v2.en.yaml
index 0823d4ab4..42ba8412b 100644
--- a/website/openapi_v2.en.yaml
+++ b/website/openapi_v2.en.yaml
@@ -13701,7 +13701,22 @@ components:
             complement_string:
               type: string
               description: Original string of the fiscal stamp.
-      required: [date, sat_signature, sat_cert_number, signature, complement_string]
+      required: [version, date, sat_signature, sat_cert_number, signature, complement_string]
+      oneOf:
+        - type: object
+          required: [version]
+          properties:
+            version:
+              type: string
+              enum: ['1.0']
+        - type: object
+          required: [version, rfc_provider_cert]
+          properties:
+            version:
+              type: string
+              enum: ['1.1']
+            rfc_provider_cert:
+              type: string
     StampProperties:
       type: object
       description: Information about the digital stamp added by the PAC.
diff --git a/website/openapi_v2.yaml b/website/openapi_v2.yaml
index d00cadc0a..2554e2e5e 100644
--- a/website/openapi_v2.yaml
+++ b/website/openapi_v2.yaml
@@ -13653,7 +13653,22 @@ components:
             complement_string:
               type: string
               description: Cadena original del timbre fiscal digital.
-      required: [date, sat_signature, sat_cert_number, signature, complement_string]
+      required: [version, date, sat_signature, sat_cert_number, signature, complement_string]
+      oneOf:
+        - type: object
+          required: [version]
+          properties:
+            version:
+              type: string
+              enum: ['1.0']
+        - type: object
+          required: [version, rfc_provider_cert]
+          properties:
+            version:
+              type: string
+              enum: ['1.1']
+            rfc_provider_cert:
+              type: string
     StampProperties:
       type: object
       description: Información sobre el timbre fiscal digital agregado por el PAC.
diff --git a/website/test/openapi-types.fixture.txt b/website/test/openapi-types.fixture.txt
index bc7fb1408..7659e76b2 100644
--- a/website/test/openapi-types.fixture.txt
+++ b/website/test/openapi-types.fixture.txt
@@ -167,7 +167,7 @@ const createdInvoiceStamp: components["schemas"]["Stamp"] | null | undefined = c
 void createdInvoiceDate;
 void createdInvoiceStamp;
 if (createdInvoiceResponse.status === 'valid' || createdInvoiceResponse.status === 'canceled') {
-  const stampedFields: [string, string, string, string, string, string, string | undefined, string | undefined] = [
+  const stampedFields: [string, string, string, string, string, string, string, string | undefined] = [
     createdInvoiceResponse.uuid,
     createdInvoiceResponse.stamp.date,
     createdInvoiceResponse.stamp.signature,
@@ -178,6 +178,10 @@ if (createdInvoiceResponse.status === 'valid' || createdInvoiceResponse.status =
     createdInvoiceResponse.stamp.legend,
   ];
   void stampedFields;
+  if (createdInvoiceResponse.stamp.version === '1.1') {
+    const certifierRfc: string = createdInvoiceResponse.stamp.rfc_provider_cert;
+    void certifierRfc;
+  }
 }
 
 // A payment summary can be reused directly in a payment complement.