I’d have to dig up the textbook sources, but the key bit is in the definition: market makers quote a two-sided market and make money from the spread [1], i.e. buying at the bid and selling at the offer. If it happens simultaneously, that’s ideal. Every second one is long or short, risk and cost are incurred. Market makers seek to minimise and manage these.
In practice, arbitrage is tough. So most market makers simulate simultaneity by hedging. For example, if longs are accumulating (e.g. due to specialist obligations) one might open shorts or buy positional puts or wing it by shorting SPYs.
An unhedged market maker is just day trading.
[1] https://www.investopedia.com/terms/m/marketmaker.asp#what-is...
Really they _quote_ simultaneously the bid and offer (although there will be times when they do only one or neither).
Saying they simultaneously buy/sell is wrong/confusing.
That wasn’t claimed. What was said is the archetype is simultaneity. That is 100% accurate for how the term “market maker” has been used, globally, since at least 1999. (Pre-GLB/LTCM and post-ECN, the term was used more broadly.)
Drift from simultaneity incurs cost and risk. Those costs and risks must be managed. If you aren’t thinking in those terms, you aren’t market making.
Zillow’s downfall mirrors that of the money-centre banks in securities dealing post-GLB leading up to the crisis. What does and does not constitute market making, which is risky but less so than leveraged day trading, was a huge area of policy concern. When non MMs think of themselves as market makers, there is a predictable set of risks they get downed by. Zillow, like so many others, fell prey to that misconception. (There is loose analogy in the ABS markets, where banks holding inventory of esoteric products, either badly hedged or hedged with a busted counterparty, got hosed.)
That’s the point of being a market maker. Managing those costs and risks well enough to make money from the spread.
Of course you can. This is the entire thesis with which HFT beat out old-school market makers in securities.
Perhaps. I haven’t been on a market-making desk for close to a decade now.
But to correct one misconception in your comment, market makers don’t commonly use limit orders. (You’d submit a quote and try to hit rebates.)
They do in the asset classes I work with, YMMV
> 1) a statement, pattern of behavior, prototype, "first" form, or a main model that other statements, patterns of behavior, and objects copy, emulate, or "merge" into. Informal synonyms frequently used for this definition include "standard example," "basic example," and the longer-form "archetypal example;" mathematical archetypes often appear as "canonical examples."
> 2) the Platonic concept of pure form, believed to embody the fundamental characteristics of a thing.
The confusion between you two seems (to me at least) to fit almost entirely within the difference between those two definition. If you are describing the ideal market maker as essentially performing arbitrage, that seems to fit the second definition pretty well, right?
Meanwhile if wpietri says that most of the work at his believed-to-be-typical example of a market maker was doing non-arbitrage stuff, that'd make sense, right? I guess in most places the main work would be managing the divergence from idealness.
I think it also leaves out that not every market maker wants to be flat instantly. The one I worked for, and at least some of our peers were sometimes happy to hold inventory for a bit when they thought the market would even out.
May I ask if this was before or after GLB (1999, for the kids following at home)? (My experience as a derivative market maker was post GLB and post crisis.)
Managing a flat book is less exciting than placing directional bets. It’s also less profitable, at least when the bets go well. Add to that the complexity of market making, particularly when derivatives enter the equation, and you get the two decades–following the advent of ECNs, turbocharged by GLB and ending in the financial crisis—in which market making desks were proprietary traders first and liquidity providers second.
Also, if you buy a swap and I simultaneously sell stock, there is both a simultaneous trade and liquidity being provisioned in a value-adding way.
Archetypal, not predominant.
> Simultaneous buying and selling is what the arb guys did. We'd buy and sell with generally short hold times
The ideal market maker is arbitraging (and eliminating the arbitrage-able inefficiency). That’s why humans were replaced by faster-trading machines everywhere they could be. In most cases, the arbitrage is synthetic or approximate, e.g. hedging an options or swaps book. But a fundamental separation between speculating and marketing making is the latter does not take a view on the assets per se, and should not be betting on their future price movement.
No market maker always achieves the ideal. But they tend towards it. Zillow didn’t have that tendency. In fact, they erected fundamental obstacles between themselves and that ideal.