If they are not on an overlapping segment (overlapping at least 5cM, preferrably more), it doesn't count. The group of folks who take the atDNA tests is relatively small and many have deep ancestries - you can easily have a match without the atDNA. If you and I share a 10cM segment on Chr 4, it means nothing if I match John Doe on Chr 5 and you match him on Chr 6. That does not create a 3-way. And even if you and I find a Common Ancestor, it may not be the one who have us the matching atDNA segment. It would be amazing if John Doe shared the same Common Ancestor with us. Make sure the overlap is larger than the cutoff you use. Jim Bartlett On 05/17/12, [email protected] wrote: Margaret (and Greg) see my post (just before yours in the digest mode). Ã All the people with whom I share that segment have each other somewhere on their DNA and except for some obvious cases where the 2 peoples' segments are shorter at opposite ends of the segment, they all match each other on that segment on c 18. Ã And everyone has multiple segments with at least one of the other members of the group.