When clients trade, especially on margin, they use the broker’s money to play. Imagine a client buys 100 shares of GameStop for $400 a share, using $20,000 of his own money and borrowing $20,000 from Robinhood. If the stock drops from $400 to $120 (as it did on Jan. 28), the client’s position may be sold for $12,000 due to the margin violation, leaving Robinhood trying to collect an unsecured $8,000 debt. Good luck. Multiply this by hundreds or thousands of similar clients. Option trading is worse because the leverage is much greater.
The broker’s risk is asymmetrical: If half its clients are winning big by buying during a short squeeze, while its short clients are suffering losses they can’t pay, the broker can’t offset these gains and losses, but must pay the winning clients while possibly eating the losing trades. It is rare, but brokers go bankrupt during market events like this.
Brokers therefore are subject to strict financial requirements, including that they maintain large security deposits at the clearinghouses. When risk rises, clearinghouses raise their requirements, even intraday. On Jan. 28, when GameStop dropped from $483 to $112, the clearinghouse DTCC raised requirements by an aggregate $7.5 billion. Brokers had to post that money to DTCC whether or not their clients had it.
Author(s): David Battan
Publication Date: 1 February 2021
Publication Site: Wall Street Journal