diff --git a/typed-racket-lib/typed-racket/types/type-table.rkt b/typed-racket-lib/typed-racket/types/type-table.rkt
index 53c07bab..76a21c41 100644
--- a/typed-racket-lib/typed-racket/types/type-table.rkt
+++ b/typed-racket-lib/typed-racket/types/type-table.rkt
@@ -69,8 +69,7 @@
                old)
            (tooltip (cons e seen) t)))
      (tooltip (list e) t)))
-  (when (optimize?)
-    (hash-update! type-table e (combine t) t)))
+  (hash-update! type-table e (combine t) t))
 
 ;; when typechecking a case-> type, types get added for
 ;; the same subexpression multiple times, combine them
diff --git a/typed-racket-test/succeed/gh-issue-343.rkt b/typed-racket-test/succeed/gh-issue-343.rkt
new file mode 100644
index 00000000..2a5d04b9
--- /dev/null
+++ b/typed-racket-test/succeed/gh-issue-343.rkt
@@ -0,0 +1,9 @@
+#lang typed/racket/base #:no-optimize
+(require typed/racket/class)
+
+(define c%
+  (class object%
+    (init-field val)
+    (super-new)))
+
+(instantiate c% (3))