Thanks for you answer, but I'm well aware of that, that's not my point.
I'm sorry I've used the misleading SDO_FILTER, I should've given the example like this:
SELECT T3.ID,T3.GEOM FROM T3
JOIN (SELECT SDO_GEOM.SDO_INTERSECTION(t2.GEOM, t1.GEOM, 1E-7) AS GEOM
FROM t1 JOIN t2 ON t2.id=t1.id) T4
ON SDO_CONTAINS(T4.GEOM, T3.GEOM);
To be exactly, the order of T4 and T3 appearing in the filter cannot be changed, due to a written specification I'm dealing with.