May 14, 2014

Who Is Selling

“Who’s selling?”

It was 2001. I’d look up and there’d be the CEO leaning in the door of my office. This was back when my buns rode the gilded surface of the IR chair. I’d look at my computer screen and our shares would be down a percent or so.

“Somebody, apparently,” I’d say. “Let me make a few calls.”

Today we have Facebook, Twitter, Pandora, iPhones, and Tesla. None of these existed in 2001. The Intercontinental Exchange, formed a year earlier to trade derivatives, now owns the NYSE. What’s remarkable to me is that against this technological wave many issuers, not counting the growing horde with Market Structure Analytics, are still making calls to get answers.

Why wouldn’t everybody be modeling market behavior and measuring periodic change? But that’s another story.

So. What if nobody’s selling and your price is down?

Impossible, you say. For price to decline, somebody has to sell.

Let me tell you about two clients releasing earnings last week.

But first, say I’m a high-frequency trader and you’re reporting. I rent (borrow) 500 shares of stock trading at $25 apiece. Say the pre-open futures are negative. At the open, I explode ahead of all others by three microseconds to place a market order to sell 500 shares. My order plunges the market 8%. I immediately cover. And for the next six hours I and my HFT compatriots trade those 500 shares amongst ourselves 23,000 times. That’s volume of 11.5 million shares.

The huge move in price prompts swaps counterparties holding insurance policies for Blackrock and Vanguard into the market, spawning big block volumes of another 6 million shares. Now you’ve traded 17.5 million shares and your price, after dropping 8%, recovers back 3% to close down 5% on the day.

So who’s selling? Technically I, an HFT firm, sold 500 shares short at the open. I probably paid a $200 finance fee for them in my margin account.

You’re the IRO. You call your exchange for answers. They see the block data, the big volumes, and conclude, yup, you had some big-time selling. Conventional wisdom says price moves, massive volume, block trades – that’s institutional.

You’re getting calls from your holders saying, “What’s going on? I didn’t think the numbers looked bad.”

Your CEO is drumming fingers on your door and grousing, “Who the HELL is selling?!”

Your Surveillance firm says UBS and Wedbush were moving big volumes. They’re trying to see if there are any clearing-relationship ties to potential institutional sellers.

The truth is neither active nor passive investors had much to do with pressure or volume, save that counterparties for passive holders had to cover exposure, helping price off lows.

Those clients I mentioned? One saw shares drop 9% day-over-day. In the data, HFT was up 170% day-over-day as price-setter, and indexes/ETFs rose 5.3%. Nothing else was up. Active investment was down. Thus, mild passive growth-selling and huge HFT hammered price. Those shares are already back in line with fair value because the selling was no more real than my 500-share example above (but the damage is done and the data are now in the historical set, affecting future algorithmic trades).

In the other case, investors were strong buyers days before results. On earnings, active investment dropped 15%, passive investment, 8%, and HFT soared 191%. These shares also coincidentally dropped 9% (programmers of algorithms know limit up/down triggers could kill their trading strategies if the move is 10% at once).

They’re still down. Active money hasn’t come back. But it’s not selling. And now we’re seeing headlines in the news string from law firms “investigating” the company for potentially misleading investors. Investors didn’t react except to stop buying.

This is the difference between calling somebody and using data models. Don’t fall in love with models (this is not a critique of Tom Brady, mind you). But the prudent IRO today uses Market Structure Analytics.

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