accumulator at work

The following are the final trades from yesterday. I bought the 4500 pre auction. I found it interesting to see the attempts that were made to make it close lower only to be blown away by late auction buying.

Whats with the XT's at 4:22, 4:37, 4:45?

Definately a bot in play - accumulating.

04:45:57 PM 0.000 0 0.00 XT
04:37:04 PM 0.000 0 0.00 XT
04:22:10 PM 0.000 0 0.00 XT
04:10:00 PM 0.620 1 0.62
04:10:00 PM 0.620 65,975 40,904.50
04:10:00 PM 0.620 7,011 4,346.82
04:10:00 PM 0.620 27,013 16,748.06
04:10:00 PM 0.620 9,992 6,195.04
04:10:00 PM 0.620 8 4.96
03:59:56 PM 0.615 1 0.62
03:59:51 PM 0.620 4,500 2,790.00 XT