diff --git a/packages/babylon/src/tokenizer/index.js b/packages/babylon/src/tokenizer/index.js
index 7203e30aac..7da2c16f3e 100644
--- a/packages/babylon/src/tokenizer/index.js
+++ b/packages/babylon/src/tokenizer/index.js
@@ -373,7 +373,8 @@ export default class Tokenizer {
     }
 
     if (next === 61) {
-      size = this.input.charCodeAt(this.state.pos + 2) === 61 ? 3 : 2;
+      // <= | >=
+      size = 2;
     }
 
     return this.finishOp(tt.relational, size);
diff --git a/packages/babylon/test/fixtures/core/regression/T2921/actual.js b/packages/babylon/test/fixtures/core/regression/T2921/actual.js
new file mode 100644
index 0000000000..55e31634f5
--- /dev/null
+++ b/packages/babylon/test/fixtures/core/regression/T2921/actual.js
@@ -0,0 +1 @@
+a <== b;
diff --git a/packages/babylon/test/fixtures/core/regression/T2921/options.json b/packages/babylon/test/fixtures/core/regression/T2921/options.json
new file mode 100644
index 0000000000..27a7b64d71
--- /dev/null
+++ b/packages/babylon/test/fixtures/core/regression/T2921/options.json
@@ -0,0 +1,3 @@
+{
+  "throws": "Unexpected token (1:4)"
+}