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Twenty-one days before a cargo of Brent blend crude oil loads at the Sullom Voe terminal, the details of the cargo are passed through the paper chains. If the cargo has not been sold by 17:00 local UK time, then the last participant to receive a call with the cargo details owns the physical cargo and has been ‘five o’clocked’. Normally this is seen as a bearish sign, as it usually happens in a market with low crude demand.
* see also daisy chain