/usr/share/php/PHPMD/Rule/ is in phpmd 2.4.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/php/PHPMD/Rule/AbstractLocalVariable.php
/usr/share/php/PHPMD/Rule/ClassAware.php
/usr/share/php/PHPMD/Rule/CleanCode/
/usr/share/php/PHPMD/Rule/CleanCode/BooleanArgumentFlag.php
/usr/share/php/PHPMD/Rule/CleanCode/ElseExpression.php
/usr/share/php/PHPMD/Rule/CleanCode/StaticAccess.php
/usr/share/php/PHPMD/Rule/Controversial/
/usr/share/php/PHPMD/Rule/Controversial/CamelCaseClassName.php
/usr/share/php/PHPMD/Rule/Controversial/CamelCaseMethodName.php
/usr/share/php/PHPMD/Rule/Controversial/CamelCaseParameterName.php
/usr/share/php/PHPMD/Rule/Controversial/CamelCasePropertyName.php
/usr/share/php/PHPMD/Rule/Controversial/CamelCaseVariableName.php
/usr/share/php/PHPMD/Rule/Controversial/Superglobals.php
/usr/share/php/PHPMD/Rule/CyclomaticComplexity.php
/usr/share/php/PHPMD/Rule/Design/
/usr/share/php/PHPMD/Rule/Design/CouplingBetweenObjects.php
/usr/share/php/PHPMD/Rule/Design/DepthOfInheritance.php
/usr/share/php/PHPMD/Rule/Design/DevelopmentCodeFragment.php
/usr/share/php/PHPMD/Rule/Design/EvalExpression.php
/usr/share/php/PHPMD/Rule/Design/ExitExpression.php
/usr/share/php/PHPMD/Rule/Design/GotoStatement.php
/usr/share/php/PHPMD/Rule/Design/LongClass.php
/usr/share/php/PHPMD/Rule/Design/LongMethod.php
/usr/share/php/PHPMD/Rule/Design/LongParameterList.php
/usr/share/php/PHPMD/Rule/Design/NpathComplexity.php
/usr/share/php/PHPMD/Rule/Design/NumberOfChildren.php
/usr/share/php/PHPMD/Rule/Design/TooManyFields.php
/usr/share/php/PHPMD/Rule/Design/TooManyMethods.php
/usr/share/php/PHPMD/Rule/Design/TooManyPublicMethods.php
/usr/share/php/PHPMD/Rule/Design/WeightedMethodCount.php
/usr/share/php/PHPMD/Rule/ExcessivePublicCount.php
/usr/share/php/PHPMD/Rule/FunctionAware.php
/usr/share/php/PHPMD/Rule/InterfaceAware.php
/usr/share/php/PHPMD/Rule/MethodAware.php
/usr/share/php/PHPMD/Rule/Naming/
/usr/share/php/PHPMD/Rule/Naming/BooleanGetMethodName.php
/usr/share/php/PHPMD/Rule/Naming/ConstantNamingConventions.php
/usr/share/php/PHPMD/Rule/Naming/ConstructorWithNameAsEnclosingClass.php
/usr/share/php/PHPMD/Rule/Naming/LongVariable.php
/usr/share/php/PHPMD/Rule/Naming/ShortMethodName.php
/usr/share/php/PHPMD/Rule/Naming/ShortVariable.php
/usr/share/php/PHPMD/Rule/UnusedFormalParameter.php
/usr/share/php/PHPMD/Rule/UnusedLocalVariable.php
/usr/share/php/PHPMD/Rule/UnusedPrivateField.php
/usr/share/php/PHPMD/Rule/UnusedPrivateMethod.php