it depends what you call peanuts.if market thought it was a...

it depends what you call peanuts.

if market thought it was a steal i.e. RIO paid half of what it is worth, they they would have made the equivalent of a $6B gain (buying for 6.7B an asset worth $13B) , $6B of instant value on a $100B MC is 6% increase in share price

if i use your $45B MC (which I am not sure it is correct) 6/45 would be a 13% gain.

with RIO share going down, the market thinks they paid what they should have (risk adjusted)

i am not saying the market is right, i am saying it is what the price at US pre market says.

P.S.
DYOR