/usr/include/curlpp/ is in libcurlpp-dev 0.7.3-6.
This file is owned by root:root, with mode 0o755.
..
/usr/include/curlpp/Easy.hpp
/usr/include/curlpp/Easy.inl
/usr/include/curlpp/Exception.hpp
/usr/include/curlpp/Form.hpp
/usr/include/curlpp/Info.hpp
/usr/include/curlpp/Info.inl
/usr/include/curlpp/Infos.hpp
/usr/include/curlpp/Multi.hpp
/usr/include/curlpp/Option.hpp
/usr/include/curlpp/Option.inl
/usr/include/curlpp/OptionBase.hpp
/usr/include/curlpp/Options.hpp
/usr/include/curlpp/Types.hpp
/usr/include/curlpp/cURLpp.hpp
/usr/include/curlpp/internal/
/usr/include/curlpp/internal/CurlHandle.hpp
/usr/include/curlpp/internal/CurlHandle.inl
/usr/include/curlpp/internal/OptionContainer.hpp
/usr/include/curlpp/internal/OptionContainer.inl
/usr/include/curlpp/internal/OptionContainerType.hpp
/usr/include/curlpp/internal/OptionList.hpp
/usr/include/curlpp/internal/OptionSetter.hpp
/usr/include/curlpp/internal/OptionSetter.inl
/usr/include/curlpp/internal/SList.hpp
/usr/include/curlpp/internal/buildconfig.h