PUBLIC is granted with Object Permissions

select owner||'.'||table_name||': '||privilege from dba_tab_privs
where grantee='PUBLIC'
and owner not in('SYS','CTXSYS','MDSYS','ODM','OLAPSYS','MTSSYS',
'ORDPLUGINS','ORDSYS','SYSTEM','WKSYS','WMSYS','XDB','LBACSYS',
'PERFSTAT','SYSMAN','DMSYS','EXFSYS');