It has been a widely-held belief in the exchange traded derivatives world that maintaining more than one pool of liquidity per contract is impossible or, at best, no more than a short-lived phenomenon - either competing contracts fail to gain traction over the long run or gain so much that the market is won by the challenging exchange.
There have been some major contracts tradeable on more than one exchange, such as the Eurodollar on Singapore Exchange and Chicago Mercantile Exchange (CME), but these have tended to be the result of time zone differences which have been all but eliminated by the switch to round-the-clock screen trading.
A situation in which a major contract has two liquidity pools of comparable size would seem to require unusual timing and circumstances. Yet two such situations have emerged in recent months: the WTI crude oil future at New York Mercantile Exchange (Nymex) has seen...