/usr/include/freeipmi/api/ is in libfreeipmi-dev 1.4.11-1.1ubuntu4.
This file is owned by root:root, with mode 0o755.
..
/usr/include/freeipmi/api/ipmi-api.h
/usr/include/freeipmi/api/ipmi-chassis-cmds-api.h
/usr/include/freeipmi/api/ipmi-dcmi-cmds-api.h
/usr/include/freeipmi/api/ipmi-device-global-cmds-api.h
/usr/include/freeipmi/api/ipmi-event-cmds-api.h
/usr/include/freeipmi/api/ipmi-firmware-firewall-command-discovery-cmds-api.h
/usr/include/freeipmi/api/ipmi-fru-inventory-device-cmds-api.h
/usr/include/freeipmi/api/ipmi-lan-cmds-api.h
/usr/include/freeipmi/api/ipmi-messaging-support-cmds-api.h
/usr/include/freeipmi/api/ipmi-oem-intel-node-manager-cmds-api.h
/usr/include/freeipmi/api/ipmi-pef-and-alerting-cmds-api.h
/usr/include/freeipmi/api/ipmi-rmcpplus-support-and-payload-cmds-api.h
/usr/include/freeipmi/api/ipmi-sdr-repository-cmds-api.h
/usr/include/freeipmi/api/ipmi-sel-cmds-api.h
/usr/include/freeipmi/api/ipmi-sensor-cmds-api.h
/usr/include/freeipmi/api/ipmi-serial-modem-cmds-api.h
/usr/include/freeipmi/api/ipmi-sol-cmds-api.h