diff --git a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/Common.kt b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/Common.kt
index 4d979d51d08..7e74c8a50f9 100644
--- a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/Common.kt
+++ b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/Common.kt
@@ -73,6 +73,7 @@ data class SpecTestCase(
     var code: String,
     var ranges: MutableList<IntRange>,
     var unexpectedBehavior: Boolean,
+    var unspecifiedBehavior: Boolean,
     val issues: MutableList<String>?
 )
 
diff --git a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/AbstractSpecTest.kt b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/AbstractSpecTest.kt
index ecbb7dbb59a..7a6167faf40 100644
--- a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/AbstractSpecTest.kt
+++ b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/AbstractSpecTest.kt
@@ -40,6 +40,7 @@ enum class SpecTestCaseInfoElementType(
 ) : SpecTestInfoElementType {
     TESTCASE_NUMBER(valuePattern = testCaseNumberPattern, required = true),
     RELEVANT_PLACES(valuePattern = relevantPlacesPattern),
+    UNSPECIFIED_BEHAVIOR
 }
 
 abstract class AbstractSpecTest(
diff --git a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/LinkedSpecTest.kt b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/LinkedSpecTest.kt
index fd94d86e07e..b9c7d421c4c 100644
--- a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/LinkedSpecTest.kt
+++ b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/models/LinkedSpecTest.kt
@@ -24,7 +24,8 @@ enum class LinkedSpecTestFileInfoElementType(
 ) : SpecTestInfoElementType {
     SPEC_VERSION(required = true),
     PLACE(valuePattern = placePattern, required = true),
-    RELEVANT_PLACES(valuePattern = relevantPlacesPattern)
+    RELEVANT_PLACES(valuePattern = relevantPlacesPattern),
+    UNSPECIFIED_BEHAVIOR
 }
 
 data class SpecPlace(
@@ -43,6 +44,7 @@ class LinkedSpecTest(
     description: String,
     cases: SpecTestCasesSet,
     unexpectedBehavior: Boolean,
+    private val unspecifiedBehavior: Boolean,
     issues: Set<String>,
     helpers: Set<String>?
 ) : AbstractSpecTest(testArea, testType, place.sections, testNumber, description, cases, unexpectedBehavior, issues, helpers) {
@@ -54,8 +56,22 @@ class LinkedSpecTest(
                 && place.sentenceNumber == pathMatcher.group("sentenceNumber").toInt()
                 && testNumber == pathMatcher.group("testNumber").toInt()
 
+    private fun getUnspecifiedBehaviourText(): String? {
+        val separatedTestCasesUnspecifiedBehaviorNumber = cases.byNumbers.count { it.value.unspecifiedBehavior }
+        val testCasesUnspecifiedBehaviorNumber = when {
+            unspecifiedBehavior -> cases.byNumbers.size
+            separatedTestCasesUnspecifiedBehaviorNumber != 0 -> separatedTestCasesUnspecifiedBehaviorNumber
+            else -> 0
+        }
+
+        return if (testCasesUnspecifiedBehaviorNumber != 0) {
+            "!!! HAS UNSPECIFIED BEHAVIOUR (in $testCasesUnspecifiedBehaviorNumber cases) !!!"
+        } else null
+    }
+
     override fun toString() = buildString {
         append("--------------------------------------------------$ls")
+        getUnspecifiedBehaviourText()?.let { append(it + ls) }
         super.getUnexpectedBehaviourText()?.let { append(it + ls) }
         append("${testArea.name.withSpaces()} $testType SPEC TEST (${testType.toString().withSpaces()})$ls")
         append("SPEC VERSION: $specVersion$ls")
diff --git a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/CommonParser.kt b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/CommonParser.kt
index 015117d10cb..324f83280eb 100644
--- a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/CommonParser.kt
+++ b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/CommonParser.kt
@@ -70,6 +70,7 @@ object CommonParser {
             parsedTestFile.testDescription,
             parsedTestFile.testCasesSet,
             parsedTestFile.unexpectedBehavior,
+            LinkedSpecTestFileInfoElementType.UNSPECIFIED_BEHAVIOR in testInfoElements,
             parsedTestFile.issues,
             parsedTestFile.helpers
         )
diff --git a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/TestCasesParser.kt b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/TestCasesParser.kt
index 59b1e213346..ba707574769 100644
--- a/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/TestCasesParser.kt
+++ b/compiler/tests-spec/tests/org/jetbrains/kotlin/spec/parsers/TestCasesParser.kt
@@ -7,6 +7,7 @@ package org.jetbrains.kotlin.spec.parsers
 
 import org.jetbrains.kotlin.spec.*
 import org.jetbrains.kotlin.spec.models.CommonInfoElementType
+import org.jetbrains.kotlin.spec.models.LinkedSpecTestFileInfoElementType
 import org.jetbrains.kotlin.spec.models.SpecTestCaseInfoElementType
 import org.jetbrains.kotlin.spec.models.SpecTestInfoElements
 import org.jetbrains.kotlin.spec.parsers.CommonParser.splitByComma
@@ -16,6 +17,7 @@ import java.util.*
 private operator fun SpecTestCase.plusAssign(addTestCase: SpecTestCase) {
     this.code += addTestCase.code
     this.unexpectedBehavior = this.unexpectedBehavior or addTestCase.unexpectedBehavior
+    this.unspecifiedBehavior = this.unspecifiedBehavior or addTestCase.unspecifiedBehavior
     this.issues?.addAll(addTestCase.issues!!)
     this.ranges.addAll(addTestCase.ranges)
 }
@@ -71,6 +73,7 @@ fun parseTestCases(testFiles: TestFiles): SpecTestCasesSet {
                 code = matcher.group("codeSL") ?: matcher.group("codeML"),
                 ranges = mutableListOf(range),
                 unexpectedBehavior = caseInfoElements.contains(CommonInfoElementType.UNEXPECTED_BEHAVIOUR),
+                unspecifiedBehavior = caseInfoElements.contains(LinkedSpecTestFileInfoElementType.UNSPECIFIED_BEHAVIOR),
                 issues = CommonParser.parseIssues(caseInfoElements[CommonInfoElementType.ISSUES]).toMutableList()
             ).save(testCasesSet.byNumbers, testCasesOfFile, testCasesByRangesOfFile, caseInfoElements)