If you aren't familiar with ToS, the data is lined up:
time of day, class traded, # traded, price+exchange, bid x ask spread
STAA - somebody opened the June 15-17.5 call spread. There was notable open interest in 17.5's, but not 15's. I'm guessing bought given the trade prices in relation to the B/A spreads.
Note the stock ripped after this hit the wires
MPC had a trade of 8000 March 90-92.5 call spreads. They appear to have been bought this afternoon just after the stock hit it's low of the day. These guys are surely a benefactor of all the cold weather this winter as propane/fuel stocks have been depleted
This has a great longer term look here too
NAT had 1.5x open interest March 10 calls trading today. Most traded around the same time through various exchanges on the offer. The chart boasts a head and shoulders bottom near a breakout. They
Mystery Trade of the day
PODD somebody fired this one off today with earnings tonight. Note there was already size in the Mar 40 C but no notable size in the others. We can guess the call spread was bought, but no idea about the angle here.