With the dramatic collapse of some huge financial institutions, unprecedented government interventions and an enormous increase in volatility all in the last couple of days, it's a great time to be an economics blogger! While there appears to be an ideological blogwar going on between the regulation hounds and the down-but-not-out libertarians, I'm not going to enlist. I am, however, in league with the libertarians on the short-sale ban. It's appalling. Skip the next three paragraphs if you know what short selling is (OK, read the next sentence if you want my only joke in this post)
In short (sorry), this is the practice of borrowing a share of stock that you don't own, selling it, and hoping the price goes down. If it does, you replace the share you borrowed with a cheaper one and keep the profit. If it goes up, the share you have to buy to close out your position costs more than you made, and you've just lost money. There are some more complicated ways to do these trades, but that's not pertinent right now.
Smart people are in agreement that short selling is, or at least can be, a good thing for market efficiency. If an asset is overvalued, the presence of short sellers will accelerate the price correction. The short sellers had better information than everyone else, and they profit deservedly. If the asset is undervalued, short sellers will lose money.
Short selling becomes unpopular when lots of assets that people pay attention to are overvalued, since it accelerates the correction that few people (including politicians) want to see. Of course, it's possible for some unsavory things to happen in the world of short sales. Like all investing, the act of short selling is (in itself) information, and can create a feedback loop. If investors see their colleagues taking short positions, and they suspect those people have good information, they may do the same. The collective effect might drive share prices far below what the market ultimately decides is an appropriate price. If that's true, the people who were late to the short-sell party will lose money. A more ominous concern is that short sellers may be disseminating bad information to cause an unfounded fall of the share price. That's fraud, and it's a legitimate fear.
I'm reminded of a case my sister worked on at the ACLU's Rhode Island affiliate. Community groups and authorities in Providence were becoming increasingly concerned that human traffickers were importing women and setting up unlicensed massage parlors that were really just exploitative brothels. Among other remedies, authorities proposed restrictions on the activities of massage parlors. As the ACLU successfully argued, these restrictions would only have affected legitimate businesses that were licensed and had already submitted to government oversight. The underground brothels would have no incentive to become legitimate. It was a clear case of confusing an illegal practice with a legitimate one, and regulating the latter.
What does this have to to with short selling? It's a legitimate practice, and it just got a blanket restriction.
If we assume that the SEC is not simply trying to manipulate stock prices upward (and i really hope that's not what this is about), then the concern - indeed, the only legitimate reason for this regulation - is that some short sellers are engaging in something malicious. Perhaps someone is spreading false information. Maybe the short sellers are actually terrorists! This has been put forward by respectable people, so i won't dismiss it. Whatever the problem was, it can't happen now that short selling is banned.
Here's my question: If you see this type of misconduct, can you target it specifically? Clearly it's preferable to locate and arrest anyone who is purposely spreading bad information. It goes without saying that we're better off apprehending terrorists than restricting their ability to make financial bets.
I'm hopeful that someone is trying to do those things. But what if you
can't find and arrest the evildoers? Or you think that will take too
long and the damage to markets will be done? Stop the feedback loop!
If an investor is spreading falsehoods - or betting based on falsehoods
- and you let the market know, the market is going to ignore the
information that it gleaned from that investor's transactions. If you
even present the compelling case that this is happening - without hard
evidence - the market will discount that investor's information. No more echo.
If you think that the market is in a feedback loop started by terrorists, tell everyone. The terrorist agenda (destruction of western civilization via financial collapse?) is substantially different from the typical investor agenda (profit maximization), and the market is unlikely to perpetuate that loop based on the idea that it's being driven by the person with the best information.
If the SEC has any concrete (or even not so concrete) evidence of misconduct among short sellers, it can achieve its agenda by simply publicizing that evidence. The echo chamber feasts off perceived information inferiority, and the SEC is well positioned to address that perception. But banning a legitimate practice because you suspect it's being exploited by evildoers is regulatory chemotherapy.







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