Exchanges repeatedly halted for brief periods, based on predetermined rules. That part was nothing special, it's something like 5 minutes at a time,
Buying to open new positions was blocked by some brokers in response to the the bump in collateral requirements they were required to fulfill. Some brokers were capable of blocking only margin account trading, but RH sounds like they blocked all buyers (plus their target market is margin account holders)
DTCC is basically interested in ensuring that trade settlement occurs. They eliminate a lot of counterparty risk, but the flipside to that is that they clearly have discretion that surprises brokers.
Buying to open new positions was blocked by some brokers in response to the the bump in collateral requirements they were required to fulfill. Some brokers were capable of blocking only margin account trading, but RH sounds like they blocked all buyers (plus their target market is margin account holders)
DTCC is basically interested in ensuring that trade settlement occurs. They eliminate a lot of counterparty risk, but the flipside to that is that they clearly have discretion that surprises brokers.