diff --git a/src/helpers/tests/validator.test.ts b/src/helpers/tests/validator.test.ts
index 8465095..d1b2a92 100644
--- a/src/helpers/tests/validator.test.ts
+++ b/src/helpers/tests/validator.test.ts
@@ -1,3 +1,4 @@
+import {MessageType} from '../constants';
 import * as validator from '../validator';
 
 describe('isNumeric', () => {
@@ -324,56 +325,63 @@ describe('validateMessage', () => {
   });
 
   test('should return false for an empty string rich message', () => {
-    expect(validator.validateMessage('', 2).success).toBe(false);
+    expect(validator.validateMessage('', MessageType.Rich).success).toBe(false);
   });
 
-  test('should return false for an empty string signal message', () => {
-    expect(validator.validateMessage('', 3).success).toBe(false);
+  test('should return true for an empty string signal message', () => {
+    expect(validator.validateMessage('', MessageType.Signal).success).toBe(
+      true
+    );
   });
 
-  test('should return false for an empty json rich message', () => {
-    expect(validator.validateMessage('{}', 2).success).toBe(false);
+  test('should return true for an empty json rich message', () => {
+    expect(validator.validateMessage('{}', MessageType.Rich).success).toBe(
+      true
+    );
   });
 
   test('should return false for an empty json signal message', () => {
-    expect(validator.validateMessage('{}', 3).success).toBe(false);
+    expect(validator.validateMessage('{}', MessageType.Signal).success).toBe(
+      true
+    );
   });
 
   test('should return true for a json rich message with the given amount', () => {
-    expect(validator.validateMessage('{"amount": "0.13"}', 2).success).toBe(
-      true
-    );
+    expect(
+      validator.validateMessage('{"amount": "0.13"}', MessageType.Rich).success
+    ).toBe(true);
   });
 
   test('should return true for a json signal message with the given amount', () => {
-    expect(validator.validateMessage('{"amount": "0.13"}', 3).success).toBe(
-      true
-    );
+    expect(
+      validator.validateMessage('{"amount": "0.13"}', MessageType.Signal)
+        .success
+    ).toBe(true);
   });
 
-  test('should return false for a json rich message with upercase coin name', () => {
+  test('should return false for a json rich message with uppercase coin name', () => {
     expect(
       validator.validateMessage(
         '{"amount": "0.13", "type": "ETH_transaction"}',
-        2
+        MessageType.Rich
       ).success
     ).toBe(false);
   });
 
-  test('should return false for a json signal message with upercase coin name', () => {
+  test('should return true for a json signal message with uppercase coin name', () => {
     expect(
       validator.validateMessage(
         '{"amount": "0.13", "type": "ETH_transaction"}',
-        3
+        MessageType.Signal
       ).success
-    ).toBe(false);
+    ).toBe(true);
   });
 
   test('should return true for a json rich message with lowercase coin name', () => {
     expect(
       validator.validateMessage(
         '{"amount": "0.13", "type": "eth_transaction"}',
-        2
+        MessageType.Rich
       ).success
     ).toBe(true);
   });
@@ -382,10 +390,31 @@ describe('validateMessage', () => {
     expect(
       validator.validateMessage(
         '{"amount": "0.13", "type": "eth_transaction"}',
-        3
+        MessageType.Signal
+      ).success
+    ).toBe(true);
+  });
+
+  test('should return true for a push notification signal message', () => {
+    expect(
+      validator.validateMessage(
+        '{"token": "DeviceToken","provider":"apns","action":"add"}',
+        MessageType.Signal
       ).success
     ).toBe(true);
   });
+
+  test('should allow a string signal message', () => {
+    expect(
+      validator.validateMessage('not a json string', MessageType.Signal).success
+    ).toBe(true);
+  });
+
+  test('should NOT allow a string rich message', () => {
+    expect(
+      validator.validateMessage('not a json string', MessageType.Rich).success
+    ).toBe(false);
+  });
 });
 
 describe('isDelegateName', () => {
diff --git a/src/helpers/validator.ts b/src/helpers/validator.ts
index 852ade0..3068126 100644
--- a/src/helpers/validator.ts
+++ b/src/helpers/validator.ts
@@ -15,7 +15,7 @@ export const isNumeric = (str: unknown): str is string =>
 
 export const parseJsonSafe = (json: string) => {
   try {
-    const result = JSON.parse(json);
+    const result = JSON.parse(json) as unknown;
 
     return {
       result,
@@ -86,33 +86,37 @@ export const validateMessage = (
     };
   }
 
-  if ([MessageType.Rich, MessageType.Signal].includes(messageType)) {
+  if ([MessageType.Rich].includes(messageType)) {
     const data = parseJsonSafe(message);
 
     const {success, result} = data;
-    if (!success || typeof result !== 'object') {
+    if (!success || typeof result !== 'object' || result === null) {
       return {
         success: false,
         error: "For rich and signal message, 'message' should be a JSON string",
       };
     }
 
-    const typeInLowerCase = result.type?.toLowerCase();
-    if (
-      typeInLowerCase?.includes('_transaction') &&
-      typeInLowerCase !== result.type
-    ) {
-      return {
-        success: false,
-        error: "Value '<coin>_transaction' must be in lower case",
-      };
-    }
-
-    if (typeof result.amount !== 'string' || !isStringAmount(result.amount)) {
-      return {
-        success: false,
-        error: "Field 'amount' must be a string, representing a number",
-      };
+    if ('type' in result && typeof result.type === 'string') {
+      const typeInLowerCase = result.type.toLowerCase();
+      if (typeInLowerCase.endsWith('_transaction')) {
+        if (typeInLowerCase !== result.type) {
+          return {
+            success: false,
+            error: "Value '<coin>_transaction' must be in lower case",
+          };
+        }
+
+        if (
+          'amount' in result &&
+          (typeof result.amount !== 'string' || !isStringAmount(result.amount))
+        ) {
+          return {
+            success: false,
+            error: "Field 'amount' must be a string, representing a number",
+          };
+        }
+      }
     }
   }