In klayout its possbile to set the length and width of the sealring arbitrarily small. This creates rather funky structures that defently arent realizable. This is shown in the attached pictures. I'm not sure if the minimum size is (50x50)u or (150x150). First picture shows structur for 50 x 50, and second picture is for 1x1.

50 x 50 micro

1 x 1 micro