next run about to start i think, page-4

My broker has just provided the following explanation -

"Regarding your previous question about NMS the small trades you are referring to are 'cross trades' meaning that the same broker is a buyer and a seller. The reason they are often small holdings is that some institutions request an order be averaged over the entire trading day
and therefore small trades go through at regular intervals. If the same broker has a sell order they are 'crossed' and don't go through the bid and offer like others do. Therefore nothing sinister or irregular about
this."

I hope that helps alleviate any concerns.