Quote from bigsnack:
ThinkorSwim. Josh and I have been talking back and forth about the huge difference in the TICK readings between data providers. From what I gather, TOS and Tradestation are pretty similar, but the other data providers look vastly different. Josh's data feed does not show most of the "extreme" readings that I see on ThinkorSwim.
My IB data looks the same as your tick charts when posted.
