I'm no expert here, but I believe it refers to trading by large institutional
investors, brokerages, arbitrage outfits, and others with enough clout, er,
money to bother with. Since the sun never sets on the EFT empire, trading goes
on around the clock anyway. Some exchanges (commodities are the one's I'm more
familiar with) have set up systems like Globex and Project Alpha (no relation
to the chip) specifically to allow individuals to gamble away their nest egg at
any hour of the day, night or weekend.
I hope that's sufficiently confusing. If so, you may send you marketable
certificates to me, care of this station.