I watch CL quotes. I watch 3 months, currently January, February, March. I notice that a lot of the time there are same number of contracts for all months on the bid side, similar situation on the ask side (but different number than the bid). So for all months there is the same number of contracts bid and for all months, there are the same number of contracts ask. Example January, February, March all bid 5 @ 90, then it will change to all months bid 10 @90. This happens all day long but of course change in unison. How can this be if there are multiple players? Is there one market maker, algorithm or syndicate that bids the same number of contracts for all these months or what is going on?