dstiles - 8:02 pm on Jun 3, 2013 (gmt 0)
Thanks for the headsup. I found only that one IP in the range in my database but it had acquired 33 hits since November 2011, the last one yesterday. Now permanently blocked (previously blocked by headers).
I found a few results at ixquick for the phrase (in quotes) "Symantec Corp Swapdrive Norton Data Services". Looks like some kind of AV site check check but I suppose it could be a fake registration (ie not Norton at all).