diff --git a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDataClassConverters.kt b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDataClassConverters.kt
index da0ab94691a..f197708d2ef 100644
--- a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDataClassConverters.kt
+++ b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDataClassConverters.kt
@@ -2562,20 +2562,6 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
-    add(FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES) { firDiagnostic ->
-        MultipleDefaultsInheritedFromSupertypesImpl(
-            firSymbolBuilder.buildSymbol(firDiagnostic.a),
-            firDiagnostic as KtPsiDiagnostic,
-            token,
-        )
-    }
-    add(FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE) { firDiagnostic ->
-        MultipleDefaultsInheritedFromSupertypesWhenNoExplicitOverrideImpl(
-            firSymbolBuilder.buildSymbol(firDiagnostic.a),
-            firDiagnostic as KtPsiDiagnostic,
-            token,
-        )
-    }
     add(FirErrors.TYPEALIAS_EXPANDS_TO_ARRAY_OF_NOTHINGS) { firDiagnostic ->
         TypealiasExpandsToArrayOfNothingsImpl(
             firSymbolBuilder.typeBuilder.buildKtType(firDiagnostic.a),
diff --git a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnostics.kt b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnostics.kt
index 77956f1791a..4f571da7800 100644
--- a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnostics.kt
+++ b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnostics.kt
@@ -1821,16 +1821,6 @@ sealed interface KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
         val containingClassName: Name
     }
 
-    interface MultipleDefaultsInheritedFromSupertypes : KtFirDiagnostic<KtElement> {
-        override val diagnosticClass get() = MultipleDefaultsInheritedFromSupertypes::class
-        val valueParameter: KtSymbol
-    }
-
-    interface MultipleDefaultsInheritedFromSupertypesWhenNoExplicitOverride : KtFirDiagnostic<KtElement> {
-        override val diagnosticClass get() = MultipleDefaultsInheritedFromSupertypesWhenNoExplicitOverride::class
-        val valueParameter: KtSymbol
-    }
-
     interface TypealiasExpandsToArrayOfNothings : KtFirDiagnostic<KtElement> {
         override val diagnosticClass get() = TypealiasExpandsToArrayOfNothings::class
         val type: KtType
diff --git a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnosticsImpl.kt b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnosticsImpl.kt
index c89d293afee..2ed9f34903b 100644
--- a/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnosticsImpl.kt
+++ b/analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnosticsImpl.kt
@@ -2187,18 +2187,6 @@ internal class CannotChangeAccessPrivilegeImpl(
     token: KtLifetimeToken,
 ) : KtAbstractFirDiagnostic<KtModifierListOwner>(firDiagnostic, token), KtFirDiagnostic.CannotChangeAccessPrivilege
 
-internal class MultipleDefaultsInheritedFromSupertypesImpl(
-    override val valueParameter: KtSymbol,
-    firDiagnostic: KtPsiDiagnostic,
-    token: KtLifetimeToken,
-) : KtAbstractFirDiagnostic<KtElement>(firDiagnostic, token), KtFirDiagnostic.MultipleDefaultsInheritedFromSupertypes
-
-internal class MultipleDefaultsInheritedFromSupertypesWhenNoExplicitOverrideImpl(
-    override val valueParameter: KtSymbol,
-    firDiagnostic: KtPsiDiagnostic,
-    token: KtLifetimeToken,
-) : KtAbstractFirDiagnostic<KtElement>(firDiagnostic, token), KtFirDiagnostic.MultipleDefaultsInheritedFromSupertypesWhenNoExplicitOverride
-
 internal class TypealiasExpandsToArrayOfNothingsImpl(
     override val type: KtType,
     firDiagnostic: KtPsiDiagnostic,
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
index d36e5e04170..1443631a4de 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
@@ -303,6 +303,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("duplicateDirrectOverriddenCallables.kt")
+        public void testDuplicateDirrectOverriddenCallables() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt");
+        }
+
         @Test
         @TestMetadata("emptyLhsClassLiterals.kt")
         public void testEmptyLhsClassLiterals() throws Exception {
@@ -345,6 +351,24 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
             runTest("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");
         }
 
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues1.kt")
+        public void testFalseNegativeDuplicateDefaultValues1() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues2.kt")
+        public void testFalseNegativeDuplicateDefaultValues2() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues3.kt")
+        public void testFalseNegativeDuplicateDefaultValues3() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt");
+        }
+
         @Test
         @TestMetadata("fileDependencyRecursion.kt")
         public void testFileDependencyRecursion() throws Exception {
@@ -729,6 +753,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
             runTest("compiler/testData/diagnostics/tests/MultipleBounds.kt");
         }
 
+        @Test
+        @TestMetadata("multipleDefaultsNoSource.kt")
+        public void testMultipleDefaultsNoSource() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt");
+        }
+
         @Test
         @TestMetadata("NamedFunctionTypeParameterInSupertype.kt")
         public void testNamedFunctionTypeParameterInSupertype() throws Exception {
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
index 621942bbff5..4fa7d948cb4 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
@@ -303,6 +303,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("duplicateDirrectOverriddenCallables.kt")
+        public void testDuplicateDirrectOverriddenCallables() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt");
+        }
+
         @Test
         @TestMetadata("emptyLhsClassLiterals.kt")
         public void testEmptyLhsClassLiterals() throws Exception {
@@ -345,6 +351,24 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
             runTest("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");
         }
 
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues1.kt")
+        public void testFalseNegativeDuplicateDefaultValues1() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues2.kt")
+        public void testFalseNegativeDuplicateDefaultValues2() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues3.kt")
+        public void testFalseNegativeDuplicateDefaultValues3() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt");
+        }
+
         @Test
         @TestMetadata("fileDependencyRecursion.kt")
         public void testFileDependencyRecursion() throws Exception {
@@ -729,6 +753,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
             runTest("compiler/testData/diagnostics/tests/MultipleBounds.kt");
         }
 
+        @Test
+        @TestMetadata("multipleDefaultsNoSource.kt")
+        public void testMultipleDefaultsNoSource() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt");
+        }
+
         @Test
         @TestMetadata("NamedFunctionTypeParameterInSupertype.kt")
         public void testNamedFunctionTypeParameterInSupertype() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
index 76e8e6a499c..7e32baf7082 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
@@ -303,6 +303,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("duplicateDirrectOverriddenCallables.kt")
+        public void testDuplicateDirrectOverriddenCallables() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt");
+        }
+
         @Test
         @TestMetadata("emptyLhsClassLiterals.kt")
         public void testEmptyLhsClassLiterals() throws Exception {
@@ -345,6 +351,24 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
             runTest("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");
         }
 
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues1.kt")
+        public void testFalseNegativeDuplicateDefaultValues1() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues2.kt")
+        public void testFalseNegativeDuplicateDefaultValues2() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues3.kt")
+        public void testFalseNegativeDuplicateDefaultValues3() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt");
+        }
+
         @Test
         @TestMetadata("fileDependencyRecursion.kt")
         public void testFileDependencyRecursion() throws Exception {
@@ -729,6 +753,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
             runTest("compiler/testData/diagnostics/tests/MultipleBounds.kt");
         }
 
+        @Test
+        @TestMetadata("multipleDefaultsNoSource.kt")
+        public void testMultipleDefaultsNoSource() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt");
+        }
+
         @Test
         @TestMetadata("NamedFunctionTypeParameterInSupertype.kt")
         public void testNamedFunctionTypeParameterInSupertype() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
index afef44f5525..d343e266411 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
@@ -303,6 +303,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("duplicateDirrectOverriddenCallables.kt")
+        public void testDuplicateDirrectOverriddenCallables() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt");
+        }
+
         @Test
         @TestMetadata("emptyLhsClassLiterals.kt")
         public void testEmptyLhsClassLiterals() throws Exception {
@@ -345,6 +351,24 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
             runTest("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");
         }
 
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues1.kt")
+        public void testFalseNegativeDuplicateDefaultValues1() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues2.kt")
+        public void testFalseNegativeDuplicateDefaultValues2() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues3.kt")
+        public void testFalseNegativeDuplicateDefaultValues3() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt");
+        }
+
         @Test
         @TestMetadata("fileDependencyRecursion.kt")
         public void testFileDependencyRecursion() throws Exception {
@@ -729,6 +753,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
             runTest("compiler/testData/diagnostics/tests/MultipleBounds.kt");
         }
 
+        @Test
+        @TestMetadata("multipleDefaultsNoSource.kt")
+        public void testMultipleDefaultsNoSource() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt");
+        }
+
         @Test
         @TestMetadata("NamedFunctionTypeParameterInSupertype.kt")
         public void testNamedFunctionTypeParameterInSupertype() throws Exception {
diff --git a/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt b/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt
index 0a172362c85..aff8ae5da7d 100644
--- a/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt
+++ b/compiler/fir/checkers/checkers-component-generator/src/org/jetbrains/kotlin/fir/checkers/generator/diagnostics/FirDiagnosticsList.kt
@@ -872,13 +872,6 @@ object DIAGNOSTICS_LIST : DiagnosticList("FirErrors") {
             parameter<Name>("containingClassName")
         }
 
-        val MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES by error<KtElement>(PositioningStrategy.DECLARATION_SIGNATURE_OR_DEFAULT) {
-            parameter<FirValueParameterSymbol>("valueParameter")
-        }
-        val MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE by error<KtElement>(PositioningStrategy.DECLARATION_NAME) {
-            parameter<FirValueParameterSymbol>("valueParameter")
-        }
-
         val TYPEALIAS_EXPANDS_TO_ARRAY_OF_NOTHINGS by error<KtElement> {
             parameter<ConeKotlinType>("type")
         }
diff --git a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
index 5b69f9db6ad..2f40d56b3f9 100644
--- a/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
+++ b/compiler/fir/checkers/gen/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
@@ -484,8 +484,6 @@ object FirErrors {
     val DATA_CLASS_OVERRIDE_DEFAULT_VALUES by error2<KtElement, FirCallableSymbol<*>, FirClassSymbol<*>>(SourceElementPositioningStrategies.DATA_MODIFIER)
     val CANNOT_WEAKEN_ACCESS_PRIVILEGE by error3<KtModifierListOwner, Visibility, FirCallableSymbol<*>, Name>(SourceElementPositioningStrategies.VISIBILITY_MODIFIER)
     val CANNOT_CHANGE_ACCESS_PRIVILEGE by error3<KtModifierListOwner, Visibility, FirCallableSymbol<*>, Name>(SourceElementPositioningStrategies.VISIBILITY_MODIFIER)
-    val MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES by error1<KtElement, FirValueParameterSymbol>(SourceElementPositioningStrategies.DECLARATION_SIGNATURE_OR_DEFAULT)
-    val MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE by error1<KtElement, FirValueParameterSymbol>(SourceElementPositioningStrategies.DECLARATION_NAME)
     val TYPEALIAS_EXPANDS_TO_ARRAY_OF_NOTHINGS by error1<KtElement, ConeKotlinType>()
     val OVERRIDING_FINAL_MEMBER by error2<KtNamedDeclaration, FirCallableSymbol<*>, Name>(SourceElementPositioningStrategies.OVERRIDE_MODIFIER)
     val RETURN_TYPE_MISMATCH_ON_INHERITANCE by error2<KtClassOrObject, FirCallableSymbol<*>, FirCallableSymbol<*>>(SourceElementPositioningStrategies.DECLARATION_NAME)
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/CommonDeclarationCheckers.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/CommonDeclarationCheckers.kt
index ca7f8ffc8af..965867236c9 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/CommonDeclarationCheckers.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/CommonDeclarationCheckers.kt
@@ -129,7 +129,6 @@ object CommonDeclarationCheckers : DeclarationCheckers() {
             FirOuterClassArgumentsRequiredChecker,
             FirPropertyInitializationChecker,
             FirDelegateFieldTypeMismatchChecker,
-            FirMultipleDefaultsInheritedFromSupertypesChecker,
             FirFiniteBoundRestrictionChecker,
         )
 
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirMultipleDefaultsInheritedFromSupertypesChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirMultipleDefaultsInheritedFromSupertypesChecker.kt
deleted file mode 100644
index 8e430cd513f..00000000000
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirMultipleDefaultsInheritedFromSupertypesChecker.kt
+++ /dev/null
@@ -1,60 +0,0 @@
-/*
- * Copyright 2010-2023 JetBrains s.r.o. and Kotlin Programming Language contributors.
- * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
- */
-
-package org.jetbrains.kotlin.fir.analysis.checkers.declaration
-
-import org.jetbrains.kotlin.diagnostics.DiagnosticReporter
-import org.jetbrains.kotlin.diagnostics.reportOn
-import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
-import org.jetbrains.kotlin.fir.analysis.checkers.directOverriddenFunctions
-import org.jetbrains.kotlin.fir.analysis.checkers.unsubstitutedScope
-import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors
-import org.jetbrains.kotlin.fir.declarations.FirRegularClass
-import org.jetbrains.kotlin.fir.isSubstitutionOrIntersectionOverride
-import org.jetbrains.kotlin.fir.scopes.processAllFunctions
-import org.jetbrains.kotlin.fir.symbols.impl.FirFunctionSymbol
-import org.jetbrains.kotlin.fir.symbols.impl.FirIntersectionOverrideFunctionSymbol
-import org.jetbrains.kotlin.fir.symbols.impl.FirNamedFunctionSymbol
-import org.jetbrains.kotlin.utils.addToStdlib.UnsafeCastFunction
-import org.jetbrains.kotlin.utils.addToStdlib.castAll
-
-object FirMultipleDefaultsInheritedFromSupertypesChecker : FirRegularClassChecker() {
-    override fun check(declaration: FirRegularClass, context: CheckerContext, reporter: DiagnosticReporter) {
-        declaration.unsubstitutedScope(context).processAllFunctions {
-            checkFunction(declaration, it, context, reporter)
-        }
-    }
-
-    private fun checkFunction(
-        declaration: FirRegularClass,
-        function: FirNamedFunctionSymbol,
-        context: CheckerContext,
-        reporter: DiagnosticReporter,
-    ) {
-        @OptIn(UnsafeCastFunction::class)
-        val overriddenFunctions = when (function) {
-            is FirIntersectionOverrideFunctionSymbol -> function.intersections.castAll<FirFunctionSymbol<*>>()
-            else -> function.directOverriddenFunctions(context)
-        }
-
-        for ((index, parameter) in function.valueParameterSymbols.withIndex()) {
-            val basesWithDefaultValues = overriddenFunctions.count { it.valueParameterSymbols[index].hasDefaultValue }
-
-            when {
-                basesWithDefaultValues <= 1 -> {
-                    continue
-                }
-                function.isSubstitutionOrIntersectionOverride -> reporter.reportOn(
-                    declaration.source, FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE,
-                    parameter, context,
-                )
-                else -> reporter.reportOn(
-                    parameter.source, FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES,
-                    parameter, context,
-                )
-            }
-        }
-    }
-}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrorsDefaultMessages.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrorsDefaultMessages.kt
index 11ae089e1b0..893b711354f 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrorsDefaultMessages.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrorsDefaultMessages.kt
@@ -359,8 +359,6 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MISSING_VAL_ON_AN
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MODIFIER_FORM_FOR_NON_BUILT_IN_SUSPEND
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MODIFIER_FORM_FOR_NON_BUILT_IN_SUSPEND_FUN
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MULTIPLE_ARGUMENTS_APPLICABLE_FOR_CONTEXT_RECEIVER
-import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES
-import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MULTIPLE_VARARG_PARAMETERS
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MULTI_FIELD_VALUE_CLASS_PRIMARY_CONSTRUCTOR_DEFAULT_PARAMETER
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.MUST_BE_INITIALIZED
@@ -1458,10 +1456,6 @@ object FirErrorsDefaultMessages : BaseDiagnosticRendererFactory() {
             FQ_NAMES_IN_TYPES
         )
 
-        val multipleDefaultsMessage = "More than one overridden descriptor declares a default value for ''{0}''. As the compiler can not make sure these values agree, this is not allowed."
-        map.put(MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES, multipleDefaultsMessage, SYMBOL)
-        map.put(MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE, multipleDefaultsMessage, SYMBOL)
-
         map.put(TYPEALIAS_EXPANDS_TO_ARRAY_OF_NOTHINGS, "Type alias expanded to malformed type ''{0}''", RENDER_TYPE)
 
         map.put(OVERRIDING_FINAL_MEMBER, "''{0}'' in ''{1}'' is final and cannot be overridden", DECLARATION_NAME, TO_STRING)
diff --git a/compiler/testData/codegen/box/bridges/kt46389.kt b/compiler/testData/codegen/box/bridges/kt46389.kt
index 101911b0629..c93a0bf7c85 100644
--- a/compiler/testData/codegen/box/bridges/kt46389.kt
+++ b/compiler/testData/codegen/box/bridges/kt46389.kt
@@ -1,5 +1,4 @@
-// IGNORE_BACKEND_K1: JS, JS_IR, JS_IR_ES6
-// IGNORE_BACKEND_K2: ANY
+// IGNORE_BACKEND: JS, JS_IR, JS_IR_ES6
 
 // The code in this test should be prohibited in the frontend, see KT-36188.
 
diff --git a/compiler/testData/codegen/box/bridges/kt46389_jvmDefault.kt b/compiler/testData/codegen/box/bridges/kt46389_jvmDefault.kt
index 5ba429ef9e1..6cfebf67867 100644
--- a/compiler/testData/codegen/box/bridges/kt46389_jvmDefault.kt
+++ b/compiler/testData/codegen/box/bridges/kt46389_jvmDefault.kt
@@ -1,5 +1,4 @@
-// IGNORE_BACKEND_K1: JS, JS_IR, JS_IR_ES6
-// IGNORE_BACKEND_K2: ANY
+// IGNORE_BACKEND: JS, JS_IR, JS_IR_ES6
 // !JVM_DEFAULT_MODE: all
 // JVM_TARGET: 1.8
 
diff --git a/compiler/testData/codegen/box/defaultArguments/function/kt36188.kt b/compiler/testData/codegen/box/defaultArguments/function/kt36188.kt
index 568f7180f77..5ed4b2a43cf 100644
--- a/compiler/testData/codegen/box/defaultArguments/function/kt36188.kt
+++ b/compiler/testData/codegen/box/defaultArguments/function/kt36188.kt
@@ -1,5 +1,4 @@
 // IGNORE_BACKEND: JS
-// IGNORE_BACKEND_K2: ANY
 
 // Test for KT-36188 bug compatibility between non-IR and IR backends
 
diff --git a/compiler/testData/codegen/box/defaultArguments/function/kt36188_2.kt b/compiler/testData/codegen/box/defaultArguments/function/kt36188_2.kt
index 950be78a89b..e0bb2edad07 100644
--- a/compiler/testData/codegen/box/defaultArguments/function/kt36188_2.kt
+++ b/compiler/testData/codegen/box/defaultArguments/function/kt36188_2.kt
@@ -1,5 +1,4 @@
 // IGNORE_BACKEND: JS
-// IGNORE_BACKEND_K2: ANY
 
 // Test for KT-36188 bug compatibility between non-IR and IR backends
 
diff --git a/compiler/testData/diagnostics/tests/annotations/rendering/multipleInheritedDefaults.fir.kt b/compiler/testData/diagnostics/tests/annotations/rendering/multipleInheritedDefaults.fir.kt
index 3d32fe44823..646f648ff0b 100644
--- a/compiler/testData/diagnostics/tests/annotations/rendering/multipleInheritedDefaults.fir.kt
+++ b/compiler/testData/diagnostics/tests/annotations/rendering/multipleInheritedDefaults.fir.kt
@@ -17,10 +17,10 @@ interface B {
     fun foo(@An a: @An Int = @An 2)
 }
 
-<!MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE("@An() a: @R|An|()  Int = ...")!>class AB1<!> : A, B
+class AB1 : A, B
 
 @An
 class AB2 : A, B {
     @An
-    override fun foo(<!MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES("@An() a: @R|An|()  Int")!>@An a: @An Int<!>) {}
+    override fun foo(@An a: @An Int) {}
 }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt b/compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt
new file mode 100644
index 00000000000..03ef21b5775
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt
@@ -0,0 +1,14 @@
+// FIR_IDENTICAL
+// ISSUE: KT-61095
+
+package org.example
+
+interface Base<P> {
+    fun child(props: Int = 10)
+}
+
+interface Intermediate<P> : Base<P>
+
+class Implementation<P>() : Intermediate<P>, Base<P> {
+    override fun child(props: Int) {}
+}
diff --git a/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt
new file mode 100644
index 00000000000..fe48226f0c2
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt
@@ -0,0 +1,16 @@
+// FIR_IDENTICAL
+// ISSUE: KT-36188
+
+interface SomeRandomBase<K> {
+    fun child(props: Int = 20)
+}
+
+interface SomeRandomOverride<J> : SomeRandomBase<J>
+
+open class Keker<P> {
+    open fun child(props: Int = 10) {}
+}
+
+class Implementation<P>() : Keker<P>(), SomeRandomOverride<P> {
+    override fun child(props: Int) {}
+}
diff --git a/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt
new file mode 100644
index 00000000000..a3df2c872b2
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt
@@ -0,0 +1,18 @@
+// FIR_IDENTICAL
+// ISSUE: KT-36188
+
+interface SomeRandomBase<K> {
+    fun child(props: Int = 20)
+}
+
+interface SomeRandomOverride<J> : SomeRandomBase<J> {
+    override fun child(props: Int) {}
+}
+
+open class Keker<P> {
+    open fun child(props: Int = 10) {}
+}
+
+class Implementation<P>() : Keker<P>(), SomeRandomOverride<P> {
+    override fun child(props: Int) {}
+}
diff --git a/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt
new file mode 100644
index 00000000000..e7b003474d2
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt
@@ -0,0 +1,18 @@
+// FIR_IDENTICAL
+// ISSUE: KT-36188
+
+interface SomeRandomBase<K> {
+    fun child(props: Int = 20)
+}
+
+interface SomeRandomOverride<J> : SomeRandomBase<J> {
+    override abstract fun child(props: Int)
+}
+
+open class Keker<P> {
+    open fun child(props: Int = 10) {}
+}
+
+class Implementation<P>() : Keker<P>(), SomeRandomOverride<P> {
+    override fun child(props: Int) {}
+}
diff --git a/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.fir.kt b/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.fir.kt
new file mode 100644
index 00000000000..20e29e31c34
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.fir.kt
@@ -0,0 +1,14 @@
+// ISSUE: KT-61095
+
+interface X {
+    fun foo(a : Int = 1) {}
+}
+
+interface Y {
+    fun foo(a : Int = 1) {}
+}
+
+object YImpl : Y
+
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>class Z1<!> : X, Y by YImpl {}
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE!>object Z1O<!> : X, Y by YImpl {}
diff --git a/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt b/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt
new file mode 100644
index 00000000000..586234394f7
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt
@@ -0,0 +1,14 @@
+// ISSUE: KT-61095
+
+interface X {
+    fun foo(a : Int = 1) {}
+}
+
+interface Y {
+    fun foo(a : Int = 1) {}
+}
+
+object YImpl : Y
+
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, MANY_IMPL_MEMBER_NOT_IMPLEMENTED, MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE!>class Z1<!> : X, Y by YImpl {}
+<!DELEGATED_MEMBER_HIDES_SUPERTYPE_OVERRIDE, MANY_IMPL_MEMBER_NOT_IMPLEMENTED, MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE!>object Z1O<!> : X, Y by YImpl {}
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.fir.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.fir.kt
new file mode 100644
index 00000000000..4de8d35e241
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.fir.kt
@@ -0,0 +1,15 @@
+interface X {
+    fun foo(a : Int = 1)
+}
+
+interface Y {
+    fun foo(a : Int = 1)
+}
+
+class Z : X, Y {
+    override fun foo(a : Int) {}
+}
+
+object ZO : X, Y {
+    override fun foo(a : Int) {}
+}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.kt
index aabe3c64642..f6aa6986f7c 100644
--- a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.kt
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypes.kt
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 interface X {
     fun foo(a : Int = 1)
 }
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.fir.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.fir.kt
deleted file mode 100644
index f1de2a8d1aa..00000000000
--- a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.fir.kt
+++ /dev/null
@@ -1,15 +0,0 @@
-interface X {
-    fun foo(a : Int = 1)
-}
-
-interface Y {
-    fun foo(a : Int = 1)
-}
-
-class Z : X, Y {
-    fun <!VIRTUAL_MEMBER_HIDDEN!>foo<!>(<!MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES!>a : Int<!>) {}
-}
-
-object ZO : X, Y {
-    fun <!VIRTUAL_MEMBER_HIDDEN!>foo<!>(<!MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES!>a : Int<!>) {}
-}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.kt
index f7160d06304..fd03fbcc64d 100644
--- a/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.kt
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultParametersInSupertypesNoOverride.kt
@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 interface X {
     fun foo(a : Int = 1)
 }
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultsAndNamesInSupertypes.fir.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultsAndNamesInSupertypes.fir.kt
index 775e199e75b..5a99fa791e6 100644
--- a/compiler/testData/diagnostics/tests/override/MultipleDefaultsAndNamesInSupertypes.fir.kt
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultsAndNamesInSupertypes.fir.kt
@@ -11,4 +11,4 @@ interface C {
 }
 
 // TODO DIFFERENT_NAMES_FOR_THE_SAME_PARAMETER_IN_SUPERTYPES reported twice
-<!MULTIPLE_DEFAULTS_INHERITED_FROM_SUPERTYPES_WHEN_NO_EXPLICIT_OVERRIDE!>class Z<!> : A, B(), C
+class Z : A, B(), C
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.fir.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.fir.kt
new file mode 100644
index 00000000000..fb7b2d1e764
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.fir.kt
@@ -0,0 +1,10 @@
+interface X {
+    fun foo(a : Int = 1)
+}
+
+interface Y {
+    fun foo(a : Int = 1)
+}
+
+<!ABSTRACT_MEMBER_NOT_IMPLEMENTED!>class Z1<!> : X, Y {} // BUG
+<!ABSTRACT_MEMBER_NOT_IMPLEMENTED!>object Z1O<!> : X, Y {} // BUG
diff --git a/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.kt b/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.kt
index 29379af071f..cf5ffb10eeb 100644
--- a/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.kt
+++ b/compiler/testData/diagnostics/tests/override/MultipleDefaultsInSupertypesNoExplicitOverride.kt
@@ -1,4 +1,3 @@
-// FIR_IDENTICAL
 interface X {
     fun foo(a : Int = 1)
 }
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
index 5fdd6a41f75..9b78b77a672 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
@@ -303,6 +303,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("duplicateDirrectOverriddenCallables.kt")
+        public void testDuplicateDirrectOverriddenCallables() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/duplicateDirrectOverriddenCallables.kt");
+        }
+
         @Test
         @TestMetadata("emptyLhsClassLiterals.kt")
         public void testEmptyLhsClassLiterals() throws Exception {
@@ -345,6 +351,24 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
             runTest("compiler/testData/diagnostics/tests/ExternalAndAbstract.kt");
         }
 
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues1.kt")
+        public void testFalseNegativeDuplicateDefaultValues1() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues1.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues2.kt")
+        public void testFalseNegativeDuplicateDefaultValues2() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues2.kt");
+        }
+
+        @Test
+        @TestMetadata("falseNegativeDuplicateDefaultValues3.kt")
+        public void testFalseNegativeDuplicateDefaultValues3() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/falseNegativeDuplicateDefaultValues3.kt");
+        }
+
         @Test
         @TestMetadata("fileDependencyRecursion.kt")
         public void testFileDependencyRecursion() throws Exception {
@@ -729,6 +753,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
             runTest("compiler/testData/diagnostics/tests/MultipleBounds.kt");
         }
 
+        @Test
+        @TestMetadata("multipleDefaultsNoSource.kt")
+        public void testMultipleDefaultsNoSource() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/multipleDefaultsNoSource.kt");
+        }
+
         @Test
         @TestMetadata("NamedFunctionTypeParameterInSupertype.kt")
         public void testNamedFunctionTypeParameterInSupertype() throws Exception {