As shares get bought and sold, depending on the amounts, sometimes there are small blocks of shares that are left over because the bid /asks are not the same. These are then put on the next buy showing up as a very small sale. This does not have to be the case here but it does happen. Stock manipulation is common place and happens many time daily but is usually more prevalent in larger short positions that will drive the price down more significantly. This is more closely watch by day traders and less concerning for those holding long. A stock with as good of a foundation as SLI appears to have will usually rise to the top with any significant news. Thus the waiting game.
Kemo