This episode of Planet Money should shed some light on it. What I understand from this episode is that there's a 2 day delay in settling trades, that's why clearing house exists.

https://www.npr.org/2021/02/02/963466346/robinhoods-very-bad...

There is a two day closing period for stock sales. During that period the exchange needs colateral to ensure when the transaction closes it will be paid for.

Typically this collateral is small, like 3% because most stocks aren’t volatile and buyers almost always pay up.

But when a stock gets incredibly volatile, there is a risk that buyers of $480 shares may refuse to pay when the price is $90 two days later. Especially when the buyers are a bunch of new retail investors who just opened accounts.

You could buy GME from most brokers because they didn’t have the GME volume Robinhood had, and they had more collateral, so the 100% collateral requirements for GME were manageable.

And the inverse; if you buy at $200 and the stock is at $400 two days later there's a risk that the person you were buying it from has disappeared (maybe they were a short seller and went bust; maybe they got seller's remorse). So RH has to reserve not just the $200 you paid for it, but also another $200 to buy the share on the open market when the counterparty fails to deliver. That's why collateral requirements are based on volatility, not momentum.

Brokerages can't guarantee trades with client money[1].

[1] https://archive.is/GFtf2

I think the requirements were calculated at the brokerage level and not the individual customer level.

One level up, I think!

Think of it like a pyramid: the clearinghouse sits at the top, the brokers are in the middle, and the rest of us dirty peasants sit at the bottom where we belong.

The clearinghouse covers 95% of trades on Wall Street. So the clearinghouse issued a decree: "we are no longer able to support opening positions for GME, AMC, and KOSS."

Since most brokers use this clearinghouse, that means almost all brokers were forced to prevent customers from buying GME.

Everyone: pikachu face

The brokers have no choice. https://youtu.be/4RS4JIEVyXM?t=96

Not quite right. There's the DTC (which carries out 95% of the trades), then there's clearing houses (sometimes a seperate entity, sometimes part of the broker: the larger ones all do their own clearing. e.g. Robinhood has their own clearing house), then there's the brokers, then the traders. The DTC said 'we need 100% collateral on these trades' (probably because they viewed there being a significant risk that someone, somewhere, would not be able to pay up for the trades they're making in a big way), and then APEX clearing (which is the clearing house used by a lot of smaller brokers but not 95% of the market) said 'we can't support opening new positions' because their liquidity would be sucked up by the requirement, blocking most of the smaller brokers. Robinhood did similar for similar reasons independently of APEX, but some other brokers not using APEX could still trade (either because they had more cash on hand or because their customers weren't buying as much of affected stocks).

> The DTC said 'we need 100% collateral on these trades' (probably because they viewed there being a significant risk that someone, somewhere, would not be able to pay up for the trades they're making in a big way

This sounds like nonsense to me. After all the job of the Clearing House is to make sure the cash is balanced correctly after the transactions. Or realistically speaking a never ending chain of transactions, thus correctly moving the cash behind back and forth in time. It's the secret of the clearing house why they have no problems that their institutional customers have single digit equity ratios (speaking about Basel II/III/...) all the time while most individuals deal with 100% equity ratio. Maybe the more reasonable explanation is that they were overwhelmed by so many small transactions.

GME was having 400% swings in a day, and being bought in a large part by brand new retail investors who had just opened accounts.

That’s a perfect storm for nonpayment issues.

> GME was having 400% swings in a day

Well, if that's what people want. At that point in time it's about buying, not selling.

> and being bought in a large part by brand new retail

> investors who had just opened accounts.

> That’s a perfect storm for nonpayment issues.

Ok but they need to go through some sort of payment processing that checks the credit rating. Even if the credit card is close to the limit, we are probably talking about amounts smaller than 1000 $. Anyone able to visit the Reddit homepage and installing the Robinhood app should have that amount of cash in hardware. FWIW, normal eCommerce payment processors deal with nonpayment issues in the sub percent range.

To be more clear DTCC gets its collateral from the broker, ie Robinhood, not the actual clients. And the broker is not allowed to use client funds for collateral.

So the DTCC has to worry about Robinhood, and Robinhood has to worry about their clients.

The Wikipedia article on DTC isn't very informative

What is the relationship between the NYSE and DTC?

The NYSE is one of the stock market centers in the US (yes, there's more than one). It's a place where you (usually virtually these days) go to agree with someone on the specifics of the trade - buy 100x GME at $420. The DTC is involved with what happens next - actually exchanging the stock and cash. In particular, they keep the records of which brokers hold how many shares of which stocks.

I highly recommend https://youtu.be/4RS4JIEVyXM?t=60 -- I didn't understand any of this myself till watching that. (Still don't! But I'm less confused.)

My understanding is that the clearing firm informs everyone "Hey, we no longer support opening positions in three stocks specifically: GameStop, AMC, and KOSS."

Literally everyone, including Robinhood, was forced to only allow people to sell GME.

Somehow Fidelity was the only market maker to avoid this -- you couldn't buy GME anywhere else due to the clearinghouse's decision.

(Why was Fidelity the only broker able to sidestep the clearinghouse's decision? An interesting mystery; perhaps someone here knows the answer.)

> Literally everyone, including Robinhood, was forced to only allow people to sell GME.

Not literally. I was able to buy w/Schwab when it was restricted by RH. I tested this specifically to see if I should change brokers.

There's more than one clearing firm in the market. The more money the clearing firm has, the more likely it'll be able to continue trading highly volatile stocks at high volume. Fidelity, as a huge financial firm that's been around for a while, had the assets to afford to keep trading it (and/or their customers weren't trading enough to put strain on them), robinhood (which has its own, small, clearing firm) couldn't, simple as that.

No, buying worked on many brokers.

This is not true, you could buy GME at almost every broker except a handful too thinly capitalized to support their volume of GME trades.

Fidelity is largest stock holder of GME.

So in the end it can be done when the right people make profit

Or rather because the trades could be done internally (Fidelity could sell off the stock they own)

EDIT: It seems my assumption was incorrect. This link posted by grandmczeb shows that RH needed more capital by a downstream dependency to ensure those trades: https://archive.is/GFtf2

Actually you were right, Fidelity did sell off all the stock they owned.

https://www.wsj.com/articles/fidelity-cashes-in-most-of-game...

https://www.bloomberg.com/news/newsletters/2021-02-11/why-ga...

They owned 13% of the company; now they own only 87 shares; they sold 9.3 million shares in 1 month.

So, during the Robinhood GME debacle, Fidelity could sidestep the issue, since they wanted to sell their own GME shares anyway, and also managed to look good in the process (no GME buying restrictions compared to Robinhood etc); win win for them

Fidelity is the largest shareholder in many stocks, it has a massive amount of client funds.