- INSTANCE:
Positive integer
*d*, collection of*d*-dimensional point sets. - SOLUTION:
A point set
*S'*congruent to a subset of each set in the collection. - MEASURE:
Size, i.e. number of elements, of the common point set
*S'*.

*Good News:*Approximable within , where*n*is the size of the smallest [6].*Bad News:*Not approximable within for some [6].*Comment:*Transformation from MAXIMUM INDEPENDENT SET. The bad news is valid even if a small gap is allowed between corresponding points.