diff --git a/j2k/src/org/jetbrains/jet/j2k/CodeBuilder.kt b/j2k/src/org/jetbrains/jet/j2k/CodeBuilder.kt
index 902ea2148fa..40e4662866c 100644
--- a/j2k/src/org/jetbrains/jet/j2k/CodeBuilder.kt
+++ b/j2k/src/org/jetbrains/jet/j2k/CodeBuilder.kt
@@ -96,10 +96,9 @@ class CodeBuilder(private val topElement: PsiElement?) {
         val prefixElements = ArrayList<PsiElement>(1)
         val postfixElements = ArrayList<PsiElement>(1)
         for ((prototype, inheritance) in element.prototypes!!) {
-            if (prototype is LightElement) continue
             assert(prototype !is PsiComment)
             assert(prototype !is PsiWhiteSpace)
-            assert(topElement.isAncestor(prototype))
+            if (!topElement.isAncestor(prototype)) continue
             prefixElements.collectPrefixElements(prototype, inheritance, notInsideElements)
             postfixElements.collectPostfixElements(prototype, inheritance, notInsideElements)
         }
diff --git a/j2k/tests/test/org/jetbrains/jet/j2k/test/JavaToKotlinConverterTestGenerated.java b/j2k/tests/test/org/jetbrains/jet/j2k/test/JavaToKotlinConverterTestGenerated.java
index 3b10a1a121e..d1c94ed60a3 100644
--- a/j2k/tests/test/org/jetbrains/jet/j2k/test/JavaToKotlinConverterTestGenerated.java
+++ b/j2k/tests/test/org/jetbrains/jet/j2k/test/JavaToKotlinConverterTestGenerated.java
@@ -3148,6 +3148,11 @@ public class JavaToKotlinConverterTestGenerated extends AbstractJavaToKotlinConv
             doTest("j2k/tests/testData/ast/typeParameters/traitDoubleParametrizationWithTwoBoundsWithExtending.java");
         }
         
+        @TestMetadata("typeFromOtherFile.java")
+        public void testTypeFromOtherFile() throws Exception {
+            doTest("j2k/tests/testData/ast/typeParameters/typeFromOtherFile.java");
+        }
+        
         @TestMetadata("where.java")
         public void testWhere() throws Exception {
             doTest("j2k/tests/testData/ast/typeParameters/where.java");
diff --git a/j2k/tests/testData/JavaApi.java b/j2k/tests/testData/JavaApi.java
index dfea9cb497f..5f62153ef3f 100644
--- a/j2k/tests/testData/JavaApi.java
+++ b/j2k/tests/testData/JavaApi.java
@@ -1,9 +1,7 @@
 package javaApi;
 
 import org.jetbrains.annotations.Nullable;
-
-import java.lang.Override;
-import java.lang.String;
+import java.util.Set;
 
 public @interface Anon1 {
     String[] value();
@@ -60,3 +58,7 @@ public class Derived extends Base {
 public class WithVarargConstructor {
     public WithVarargConstructor(int p, Object... objects) { }
 }
+
+class T {
+    public Set<String> set;
+}
\ No newline at end of file
diff --git a/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.java b/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.java
new file mode 100644
index 00000000000..1b5474b3ce8
--- /dev/null
+++ b/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.java
@@ -0,0 +1,8 @@
+import java.util.*;
+import javaApi.T;
+
+class A {
+    public Object foo(T t) {
+        return Collections.nCopies(1, t.set);
+    }
+}
\ No newline at end of file
diff --git a/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.kt b/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.kt
new file mode 100644
index 00000000000..3d2734b1e1e
--- /dev/null
+++ b/j2k/tests/testData/ast/typeParameters/typeFromOtherFile.kt
@@ -0,0 +1,9 @@
+import java.util.*
+import javaApi.T
+import kotlin.Set
+
+class A {
+    public fun foo(t: T): Any {
+        return Collections.nCopies<Set<String>>(1, t.set)
+    }
+}
\ No newline at end of file