/usr/include/COS/ is in libcos4-dev 4.2.2-0.8.
This file is owned by root:root, with mode 0o755.
..
/usr/include/COS/COS_sysdep.h
/usr/include/COS/CosCollection.hh
/usr/include/COS/CosCompoundLifeCycle.hh
/usr/include/COS/CosContainment.hh
/usr/include/COS/CosEventChannelAdmin.hh
/usr/include/COS/CosEventComm.hh
/usr/include/COS/CosExternalization.hh
/usr/include/COS/CosExternalizationContainment.hh
/usr/include/COS/CosExternalizationReference.hh
/usr/include/COS/CosGraphs.hh
/usr/include/COS/CosLicensingManager.hh
/usr/include/COS/CosLifeCycle.hh
/usr/include/COS/CosLifeCycleContainment.hh
/usr/include/COS/CosLifeCycleReference.hh
/usr/include/COS/CosNotification.hh
/usr/include/COS/CosNotifyChannelAdmin.hh
/usr/include/COS/CosNotifyComm.hh
/usr/include/COS/CosNotifyFilter.hh
/usr/include/COS/CosObjectIdentity.hh
/usr/include/COS/CosPersistenceDDO.hh
/usr/include/COS/CosPersistenceDS_CLI.hh
/usr/include/COS/CosPersistencePDS.hh
/usr/include/COS/CosPersistencePDS_DA.hh
/usr/include/COS/CosPersistencePID.hh
/usr/include/COS/CosPersistencePO.hh
/usr/include/COS/CosPersistencePOM.hh
/usr/include/COS/CosPropertyService.hh
/usr/include/COS/CosQuery.hh
/usr/include/COS/CosQueryCollection.hh
/usr/include/COS/CosReference.hh
/usr/include/COS/CosRelationships.hh
/usr/include/COS/CosStream.hh
/usr/include/COS/CosTime.hh
/usr/include/COS/CosTrading.hh
/usr/include/COS/CosTradingDynamic.hh
/usr/include/COS/CosTradingRepos.hh
/usr/include/COS/LifeCycleService.hh
/usr/include/COS/TimeBase.hh