diff --git a/core/descriptors/src/org/jetbrains/kotlin/name/FqName.java b/core/descriptors/src/org/jetbrains/kotlin/name/FqName.java
index cece2cd1c1f..65317a2218a 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/name/FqName.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/name/FqName.java
@@ -39,28 +39,15 @@ public final class FqName extends FqNameBase {
 
     public FqName(@NotNull String fqName) {
         this.fqName = new FqNameUnsafe(fqName, this);
-
-        validateFqName();
     }
 
     public FqName(@NotNull FqNameUnsafe fqName) {
         this.fqName = fqName;
-
-        validateFqName();
     }
 
     private FqName(@NotNull FqNameUnsafe fqName, FqName parent) {
         this.fqName = fqName;
         this.parent = parent;
-
-        validateFqName();
-    }
-
-
-    private void validateFqName() {
-        if (!isValidAfterUnsafeCheck(fqName.asString())) {
-            throw new IllegalArgumentException("incorrect fq name: " + fqName);
-        }
     }
 
     /*package*/ static boolean isValidAfterUnsafeCheck(@NotNull String qualifiedName) {
diff --git a/core/descriptors/src/org/jetbrains/kotlin/name/FqNameUnsafe.java b/core/descriptors/src/org/jetbrains/kotlin/name/FqNameUnsafe.java
index db7d456e51d..a4a0b61fe10 100644
--- a/core/descriptors/src/org/jetbrains/kotlin/name/FqNameUnsafe.java
+++ b/core/descriptors/src/org/jetbrains/kotlin/name/FqNameUnsafe.java
@@ -41,29 +41,16 @@ public final class FqNameUnsafe extends FqNameBase {
     FqNameUnsafe(@NotNull String fqName, @NotNull FqName safe) {
         this.fqName = fqName;
         this.safe = safe;
-
-        validateFqName();
     }
 
     public FqNameUnsafe(@NotNull String fqName) {
         this.fqName = fqName;
-
-        validateFqName();
     }
 
     private FqNameUnsafe(@NotNull String fqName, FqNameUnsafe parent, Name shortName) {
         this.fqName = fqName;
         this.parent = parent;
         this.shortName = shortName;
-
-        validateFqName();
-    }
-
-
-    private void validateFqName() {
-        if (!isValid(fqName)) {
-            throw new IllegalArgumentException("incorrect fq name: " + fqName);
-        }
     }
 
     public static boolean isValid(@Nullable String qualifiedName) {