diff --git a/tests/co19/co19-co19.status b/tests/co19/co19-co19.status
index 711dbb7b468..217647319d4 100644
--- a/tests/co19/co19-co19.status
+++ b/tests/co19/co19-co19.status
@@ -20,10 +20,9 @@ Language/Generics/Superbounded_types/typedef2_A01_t04: Skip # Non function type
 Language/Generics/parameter_A01_t03: Skip # Type aliases are not fully implemented
 Language/Generics/syntax_t31: Skip # Type aliases are not fully implemented
 Language/Generics/typedef_A01_t10: Skip # Type aliases are not fully implemented
-Language/Reference/Lexical_Rules/*: Skip # Not migrated to NNBD
-Language/Reference/Lexical_Rules/Comments/*: Skip # Not migrated to NNBD
-Language/Reference/Lexical_Rules/Reserved_Words/*: Skip # Not migrated to NNBD
-Language/Reference/Operator_Precedence/*: Skip # Not migrated to NNBD
+Language/Reference/Operator_Precedence/precedence_01_assignment_t14: Skip # Triple shift is not implemented yet
+Language/Reference/Operator_Precedence/precedence_12_Shift_t04: Skip # Triple shift is not implemented yet
+Language/Reference/Operator_Precedence/precedence_t05: Skip # Triple shift is not implemented yet
 Language/Statements/Assert/*: Skip # Not migrated to NNBD
 Language/Statements/Blocks/*: Skip # Not migrated to NNBD
 Language/Statements/Break/*: Skip # Not migrated to NNBD
diff --git a/tests/co19/co19-dart2js.status b/tests/co19/co19-dart2js.status
index a3cfd33b67f..d6f8c838724 100644
--- a/tests/co19/co19-dart2js.status
+++ b/tests/co19/co19-dart2js.status
@@ -18,6 +18,7 @@ Language/Expressions/Shift/integer_t01: SkipByDesign # big integer cannot be rep
 Language/Expressions/Shift/integer_t02: SkipByDesign # big integer cannot be represented in JavaScript
 Language/Expressions/Spawning_an_Isolate/new_isolate_t01: SkipByDesign
 Language/Metadata/before*: Skip # dart:mirrors not supported https://github.com/dart-lang/co19/issues/523.
+Language/Reference/Operator_Precedence/precedence_15_unary_prefix_t08: SkipByDesign # binary '~' produces different results in JavaScript and Dart
 LibTest/io/*: SkipByDesign # dart:io not supported.
 LibTest/isolate/*: SkipByDesign # dart:isolate not supported.
 
diff --git a/tests/co19/co19-dartdevc.status b/tests/co19/co19-dartdevc.status
index c8331495b0e..08f3b562d0e 100644
--- a/tests/co19/co19-dartdevc.status
+++ b/tests/co19/co19-dartdevc.status
@@ -69,6 +69,7 @@ Language/Expressions/Shift/integer_t01: SkipByDesign # big integer cannot be rep
 Language/Expressions/Shift/integer_t02: SkipByDesign # big integer cannot be represented in JavaScript
 Language/Expressions/Spawning_an_Isolate/new_isolate_t01: SkipByDesign # dart:isolate not supported.
 Language/Metadata/before*: Skip # dart:mirrors not supported https://github.com/dart-lang/co19/issues/523.
+Language/Reference/Operator_Precedence/precedence_15_unary_prefix_t08: SkipByDesign # binary '~' produces different results in JavaScript and Dart
 Language/Types/Interface_Types/subtype_t27: Skip # Times out
 Language/Types/Interface_Types/subtype_t28: Skip # Times out
 LibTest/html/CanvasRenderingContext2D/addEventListener_A01_t03: Skip # Times out