/usr/include/boost/thread/ is in libboost1.46-dev 1.46.1-7ubuntu3.
This file is owned by root:root, with mode 0o755.
..
/usr/include/boost/thread/barrier.hpp
/usr/include/boost/thread/condition.hpp
/usr/include/boost/thread/condition_variable.hpp
/usr/include/boost/thread/detail/
/usr/include/boost/thread/detail/config.hpp
/usr/include/boost/thread/detail/force_cast.hpp
/usr/include/boost/thread/detail/move.hpp
/usr/include/boost/thread/detail/platform.hpp
/usr/include/boost/thread/detail/singleton.hpp
/usr/include/boost/thread/detail/thread.hpp
/usr/include/boost/thread/detail/thread_group.hpp
/usr/include/boost/thread/detail/thread_heap_alloc.hpp
/usr/include/boost/thread/detail/thread_interruption.hpp
/usr/include/boost/thread/detail/tss_hooks.hpp
/usr/include/boost/thread/exceptions.hpp
/usr/include/boost/thread/future.hpp
/usr/include/boost/thread/locks.hpp
/usr/include/boost/thread/mutex.hpp
/usr/include/boost/thread/once.hpp
/usr/include/boost/thread/pthread/
/usr/include/boost/thread/pthread/condition_variable.hpp
/usr/include/boost/thread/pthread/condition_variable_fwd.hpp
/usr/include/boost/thread/pthread/mutex.hpp
/usr/include/boost/thread/pthread/once.hpp
/usr/include/boost/thread/pthread/pthread_mutex_scoped_lock.hpp
/usr/include/boost/thread/pthread/recursive_mutex.hpp
/usr/include/boost/thread/pthread/shared_mutex.hpp
/usr/include/boost/thread/pthread/thread_data.hpp
/usr/include/boost/thread/pthread/thread_heap_alloc.hpp
/usr/include/boost/thread/pthread/timespec.hpp
/usr/include/boost/thread/recursive_mutex.hpp
/usr/include/boost/thread/shared_mutex.hpp
/usr/include/boost/thread/thread.hpp
/usr/include/boost/thread/thread_time.hpp
/usr/include/boost/thread/tss.hpp
/usr/include/boost/thread/win32/
/usr/include/boost/thread/win32/basic_recursive_mutex.hpp
/usr/include/boost/thread/win32/basic_timed_mutex.hpp
/usr/include/boost/thread/win32/condition_variable.hpp
/usr/include/boost/thread/win32/interlocked_read.hpp
/usr/include/boost/thread/win32/mutex.hpp
/usr/include/boost/thread/win32/once.hpp
/usr/include/boost/thread/win32/recursive_mutex.hpp
/usr/include/boost/thread/win32/shared_mutex.hpp
/usr/include/boost/thread/win32/thread_data.hpp
/usr/include/boost/thread/win32/thread_heap_alloc.hpp
/usr/include/boost/thread/win32/thread_primitives.hpp
/usr/include/boost/thread/xtime.hpp