SNY made a $93.50 cash bid for CHTT common stock. CHTT closed $69.98 on Friday, so the takeover price is a $23.52 or 33.6% premium. There wasn't any obvious order flow on Friday in the calls, but a closer look uncovers at the very least a coincidence if not a hint of the possible deal. The open interest (OI) chart for the Jan 70, 75 and 80 calls (the highest strikes available at the time) illustrate that within two weeks the OI for all lines began to increase from 0 to 567, 1232 and 2092 respectively. Using average prices (or estimates of average prices) for the options I see this profit from those trades by line (buying on offer, selling on bid): 70: Buy 567 for $1.45 <---> Sell now @ $22.80 <---> $1.2 million 75: Buy 1232 for $0.30 <---> Sell now @ $17.80 <---> $2.2 million 80: Buy 2092 for $0.15 <---> Sell now @ $12.80 <---> $2.6 million For a total $6 million gain on $151,000 or 3900% in 13 days. This type of order flow is much more common than the uber obvious 5,000 call purchases on the offer with ten minutes to go in the trading day. But, note that the dollar amount won is just as big. Understanding order flow can be an exercise in memory and trend identification. At other times it's just identifying the obvious. The accumulation of a position can be just as telling (if not more so) as the one time big bet. You can see details, trades, prices, charts on my blog: http://livevol.blogspot.com/2009/12/chattem-chtt-understanding-order-in.html