In my view the fact that the aggregate volumes are quite low would indicate that no "major" is involved in this. Plus I believe that it being as obvious as it is would have mainstream companies shy away.
One of the other participants suggested that it almost appears to be a computer program and I can see the logic in that view. I suspect it is one individual or some small group that perhaps are trying out some process to determine the results of this nature of trading.
I don't think it means very much to we who are of the "long" view but I believe that the originator is achieving their perhaps goal of raising some unsettled feelings amongst the average investor which may well move some to sell out.
Onward and Upward