At the time the lot became nonconforming, it did not adjoin other lots held in the same or related ownership with which it could be merged to create a conforming or less nonconforming lot, except where such adjoining lots were created by a subdivision approved by the Planning Board or duly filed in the Dutchess County Clerk's Office. For purposes of this section, related ownership includes, but is not limited to, individuals related by marriage or kinship, individuals who are members of the same partnership, and corporate entities with common parent corporate entities or stockholders.