diff --git a/lib/rules/no-typos.js b/lib/rules/no-typos.js
index f9c798a9fb..8fb6ba27ee 100644
--- a/lib/rules/no-typos.js
+++ b/lib/rules/no-typos.js
@@ -126,8 +126,7 @@ module.exports = {
 
     function reportErrorIfClassPropertyCasingTypo(node, propertyName) {
       if (propertyName === 'propTypes' || propertyName === 'contextTypes' || propertyName === 'childContextTypes') {
-        const propsNode = node && node.parent && node.parent.type === 'AssignmentExpression' && node.parent.right;
-        checkValidPropObject(propsNode);
+        checkValidPropObject(node);
       }
       STATIC_CLASS_PROPERTIES.forEach(CLASS_PROP => {
         if (propertyName && CLASS_PROP.toLowerCase() === propertyName.toLowerCase() && CLASS_PROP !== propertyName) {
@@ -176,7 +175,7 @@ module.exports = {
 
         const tokens = context.getFirstTokens(node, 2);
         const propertyName = tokens[1].value;
-        reportErrorIfClassPropertyCasingTypo(node, propertyName);
+        reportErrorIfClassPropertyCasingTypo(node.value, propertyName);
       },
 
       MemberExpression: function(node) {
@@ -193,9 +192,10 @@ module.exports = {
 
         if (
           relatedComponent &&
-          (utils.isES6Component(relatedComponent.node) || utils.isReturningJSX(relatedComponent.node))
+          (utils.isES6Component(relatedComponent.node) || utils.isReturningJSX(relatedComponent.node)) &&
+          (node.parent && node.parent.type === 'AssignmentExpression' && node.parent.right)
         ) {
-          reportErrorIfClassPropertyCasingTypo(node, propertyName);
+          reportErrorIfClassPropertyCasingTypo(node.parent.right, propertyName);
         }
       },
 
diff --git a/tests/lib/rules/no-typos.js b/tests/lib/rules/no-typos.js
index 8ae187ff5b..3327b9d13d 100644
--- a/tests/lib/rules/no-typos.js
+++ b/tests/lib/rules/no-typos.js
@@ -935,6 +935,34 @@ ruleTester.run('no-typos', rule, {
     errors: [{
       message: 'Typo in prop type chain qualifier: isrequired'
     }]
+  }, {
+    code: `
+      import PropTypes from "prop-types";
+      class Component extends React.Component {
+        static propTypes = {
+          a: PropTypes.number.isrequired
+        }
+      };
+    `,
+    parser: 'babel-eslint',
+    parserOptions: parserOptions,
+    errors: [{
+      message: 'Typo in prop type chain qualifier: isrequired'
+    }]
+  }, {
+    code: `
+      import PropTypes from "prop-types";
+      class Component extends React.Component {
+        static propTypes = {
+          a: PropTypes.Number
+        }
+      };
+    `,
+    parser: 'babel-eslint',
+    parserOptions: parserOptions,
+    errors: [{
+      message: 'Typo in declared prop type: Number'
+    }]
   }, {
     code: `
       import PropTypes from "prop-types";