diff --git a/packages/babel-plugin-minify-simplify/__tests__/simplify-test.js b/packages/babel-plugin-minify-simplify/__tests__/simplify-test.js
index 4f1ee3689..ade42b62b 100644
--- a/packages/babel-plugin-minify-simplify/__tests__/simplify-test.js
+++ b/packages/babel-plugin-minify-simplify/__tests__/simplify-test.js
@@ -1969,6 +1969,36 @@ describe("simplify-plugin", () => {
   `
   );
 
+  thePlugin(
+    "should simplify common conditional operations 2",
+    `
+      function h1() { return a && b ? (foo(), true) : false }
+    `,
+    `
+      function h1() {
+        return !!(a && b) && (foo(), true);
+      }
+    `
+  );
+
+  thePlugin(
+    "should fix issue#689",
+    `
+      function foo(object, property, value) {
+        if (object && property) {
+          object[property] = value;
+          return true;
+        }
+        return false;
+      }
+    `,
+    `
+      function foo(object, property, value) {
+        return !!(object && property) && (object[property] = value, true);
+      }
+    `
+  );
+
   // From UglifyJS
   thePlugin.inEachLine(
     "should simplify logical expression of the following forms of && by compressing to the right",
diff --git a/packages/babel-plugin-minify-simplify/src/conditional-expression.js b/packages/babel-plugin-minify-simplify/src/conditional-expression.js
index deb980e17..17dfc8a84 100644
--- a/packages/babel-plugin-minify-simplify/src/conditional-expression.js
+++ b/packages/babel-plugin-minify-simplify/src/conditional-expression.js
@@ -31,7 +31,7 @@ module.exports = t => {
 
       [EX, EX, true, (e, c) => or(not(e), c)],
 
-      [LE, EX, false, (e, c) => and(e, c)],
+      [LE, EX, false, (e, c) => and(notnot(e), c)],
       [EX, EX, false, (e, c) => and(notnot(e), c)]
     ]);