diff --git a/src/fast-path.js b/src/fast-path.js
index 74e994d07..990d7ed0c 100644
--- a/src/fast-path.js
+++ b/src/fast-path.js
@@ -405,6 +405,7 @@ FPp.needsParens = function(assumeExpressionContext) {
 
     case "ClassExpression":
       switch (parent.type) {
+        case "BinaryExpression":
         case "ExportDefaultDeclaration":
         case "ExpressionStatement":
           return true;
diff --git a/tests/classes/__snapshots__/jsfmt.spec.js.snap b/tests/classes/__snapshots__/jsfmt.spec.js.snap
index 4644dbbd2..d2de13bf1 100644
--- a/tests/classes/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/classes/__snapshots__/jsfmt.spec.js.snap
@@ -74,6 +74,19 @@ new E().x;
 "
 `;
 
+exports[`test binary.js 1`] = `
+"(class {}) + 1;
+(class a {}) + 1;
+(class extends b {}) + 1;
+(class a extends b {}) + 1;
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+(class {}) + 1;
+(class a {}) + 1;
+(class extends b {}) + 1;
+(class a extends b {}) + 1;
+"
+`;
+
 exports[`test class_shapes.js 1`] = `
 "/* @flow */
 
diff --git a/tests/classes/binary.js b/tests/classes/binary.js
new file mode 100644
index 000000000..f60f9c8f7
--- /dev/null
+++ b/tests/classes/binary.js
@@ -0,0 +1,4 @@
+(class {}) + 1;
+(class a {}) + 1;
+(class extends b {}) + 1;
+(class a extends b {}) + 1;