Record 1.  ABC|AVC1|1234|
               xyz|abc
Record 2.  ABC1|AVC1|12334|
               xyz
               |ABC
Record 3. ABC1|AVC1|12334|xyz|ABC

1  with t as (select 1 as rn, 'ABC|AVC1|1234|' as txt from dual union all
  2             select 2, 'xyz|abc' from dual union all
  3             select 3, 'ABC1|AVC1|12334|' from dual union all
  4             select 4, 'xyz' from dual union all
  5             select 5, '|ABC' from dual union all
  6             select 6, 'ABC1|AVC1|12334|xyz|ABC' from dual)
  7  -- END OF TEST DATA
  8  select rn, txt
  9  from (
 10        select rn, regexp_substr(txt, '^[^|]+\|[^|]+\|[^|]+\|[^|]+\|[^|]+') as txt
 11              ,case when s < nvl(lag(s) over (order by rn),999) then 1 else 0 end as s
 12        from (
 13              select rn, replace(txt||'|'||lead(txt) over (order by rn)
 14                                    ||'|'||lead(txt,2) over (order by rn)
 15                                    ||'|'||lead(txt,3) over (order by rn)
 16                                    ||'|'||lead(txt,4) over (order by rn),'||','|') as txt
 17                       ,mod(sum(length(regexp_replace(txt,'[^|]'))) over (order by rn),5) as s
 18              from t
 19             )
 20       )
 21  where s = 1
 22* order by rn
SQL> / 
 
        RN TXT
---------- ------------------------------
         1 ABC|AVC1|1234|xyz|abc
         3 ABC1|AVC1|12334|xyz|ABC
         6 ABC1|AVC1|12334|xyz|ABC
 
SQL>