diff --git a/README.md b/README.md
index d8a5d72..907cd2c 100644
--- a/README.md
+++ b/README.md
@@ -1,10 +1,10 @@
-# A JavaScript module of validation functions 
-
-A validation function returns true or false.
+# A JavaScript module of validation functions
 
 Validation functions are used to verify data integrity, but are not relied upon to verify data authenticity.
-In other words: a validation function is primarily a safeguard against simple user errors or random input. 
-It is designed to protect against accidental errors, not malicious attacks.
+In other words: a validation function is primarily a safeguard against simple human transcription errors 
+or random input. It is designed to protect against accidental errors, not malicious attacks. 
+
+A validation function returns true or false.
 
 ## Validation functions
 
@@ -21,9 +21,8 @@ This module contains several validation functions:
 - National Insurance number (NI)
 - Numéro d'inscription au Répertoire (NIR)
 - Canadian Social Insurance Number (SIN)
-- Social Security Number (SSN)
 - Österreichische Sozialversicherungsnummer (ÖVSNR)
-- Deutscher Personalausweis
+- Personalausweis-ID oder Pass-ID (PID)
 - Deutsche Rentenversicherungsnummer (VSNR)
 - Payment card numbers like VISA or Mastercard (PAN)
 
diff --git a/package.json b/package.json
index 27d4177..a4b70de 100644
--- a/package.json
+++ b/package.json
@@ -1,14 +1,18 @@
 {
   "name": "@e2n/validators",
-  "version": "1.0.0",
   "description": "A module of common validation functions.",
+  "version": "1.0.0",
   "keywords": [
     "validation",
     "validators",
     "predicates"
   ],
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/E2N/validators.git"
+  },
   "homepage": "https://github.com/E2N/validators",
-  "license": "Unlicense",
+  "license": "MIT",
   "type": "commonjs",
   "devDependencies": {
     "jest": "^29.7.0",
diff --git a/validators.js b/validators.js
index fcff208..58b7c4e 100644
--- a/validators.js
+++ b/validators.js
@@ -19,7 +19,9 @@
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
-/*
+ */
+
+"use strict";
 
 /* IBAN REGISTRY Release 95 – Jul 2023                                                                 */
 const iban_registry = new Map(Object.entries({
@@ -595,6 +597,30 @@ function sin(input) {
     return sum % 10 === 0;
 }
 
+function pid(input) {
+    /* Null, undefined and blank check                                                                      */
+    if (!input) {
+        return false;
+    }
+
+    /* Type check                                                                                           */
+    if (typeof input !== "string") {
+        return false;
+    }
+
+    /* Length check                                                                                          */
+    if (input.length !== 10) {
+        return false;
+    }
+
+    let check_digit= parseInt(input.charAt(9));
+    const weights = [7, 3, 1];
+
+    /* https://de.wikipedia.org/wiki/Ausweisnummer#Berechnung_der_Prüfziffern */
+
+    return false;
+}
+
 module.exports = {
     bbnr,
     cf,
@@ -606,6 +632,7 @@ module.exports = {
     nhs,
     nir,
     pan,
+    pid,
     sin,
     vsnr
 }
\ No newline at end of file
diff --git a/validators.test.js b/validators.test.js
index 12fb1fb..85e6b4b 100644
--- a/validators.test.js
+++ b/validators.test.js
@@ -302,4 +302,11 @@ describe("Canadian Social Insurance Number (SIN)", function() {
     test.each([
         ["046454286", true]
     ])("%s", (input, expected) => expect(validators.sin(input)).toBe(expected));
+});
+
+describe("Personalausweis-ID oder Pass-ID (PID)", function() {
+    test.each([
+        ["T220001293", true],
+        ["1220001297", true]
+    ])("%s", (input, expected) => expect(validators.pid(input)).toBe(expected));
 });
\ No newline at end of file