I am wondering if a bank that sells derivatives (Warrants, Turbos ...) can "cancel" their products after a very bad event.
Today, I buy 5000 PUT warrants.
Then tomorrow, a market crash happens, so my warrants has much more value ! But this scenario is not good for the bank.
Can the issuer of my warrants artificially change the value of my warrants (to the value of yesterday, per example) because they don't want to lose too much money ?