At today’s close, RDS-A has an 8% premium to RDS-B, which makes absolutely no sense insofar as the two classes of shares have the same economic interest (as you noted). This discrepancy must be the result sign of a poorly functioning market for ADSs due to the severe volatility in securities markets generally.
Why RDS-A (+7.0% today) is still trading at a hefty (7%) premium to RDS-B (+4.4% today) remains an enigma. Six days ago (in #msg-154393879) I opined that the discrepancy “must be the result sign of a poorly functioning market for ADSs due to the severe volatility in securities markets generally.”
That’s not much of an explanation, but it’s the best one I have.