/usr/share/civicrm/Civi/API/ is in civicrm-common 4.7.1+dfsg-2ubuntu1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/civicrm/Civi/API/Event/
/usr/share/civicrm/Civi/API/Event/AuthorizeEvent.php
/usr/share/civicrm/Civi/API/Event/Event.php
/usr/share/civicrm/Civi/API/Event/ExceptionEvent.php
/usr/share/civicrm/Civi/API/Event/PrepareEvent.php
/usr/share/civicrm/Civi/API/Event/ResolveEvent.php
/usr/share/civicrm/Civi/API/Event/RespondEvent.php
/usr/share/civicrm/Civi/API/Events.php
/usr/share/civicrm/Civi/API/Exception/
/usr/share/civicrm/Civi/API/Exception/NotImplementedException.php
/usr/share/civicrm/Civi/API/Exception/UnauthorizedException.php
/usr/share/civicrm/Civi/API/ExternalBatch.php
/usr/share/civicrm/Civi/API/Kernel.php
/usr/share/civicrm/Civi/API/Provider/
/usr/share/civicrm/Civi/API/Provider/AdhocProvider.php
/usr/share/civicrm/Civi/API/Provider/MagicFunctionProvider.php
/usr/share/civicrm/Civi/API/Provider/ProviderInterface.php
/usr/share/civicrm/Civi/API/Provider/ReflectionProvider.php
/usr/share/civicrm/Civi/API/Provider/StaticProvider.php
/usr/share/civicrm/Civi/API/Request.php
/usr/share/civicrm/Civi/API/SelectQuery.php
/usr/share/civicrm/Civi/API/Subscriber/
/usr/share/civicrm/Civi/API/Subscriber/APIv3SchemaAdapter.php
/usr/share/civicrm/Civi/API/Subscriber/ChainSubscriber.php
/usr/share/civicrm/Civi/API/Subscriber/DynamicFKAuthorization.php
/usr/share/civicrm/Civi/API/Subscriber/I18nSubscriber.php
/usr/share/civicrm/Civi/API/Subscriber/PermissionCheck.php
/usr/share/civicrm/Civi/API/Subscriber/TransactionSubscriber.php
/usr/share/civicrm/Civi/API/Subscriber/WhitelistSubscriber.php
/usr/share/civicrm/Civi/API/Subscriber/WrapperAdapter.php
/usr/share/civicrm/Civi/API/Subscriber/XDebugSubscriber.php
/usr/share/civicrm/Civi/API/WhitelistRule.php