Shorting Obvious Pump and Dump Penny Stocks
Shorting penny stocks is very risky.  For example, read this investopedia article, which explains some of the problems.  In general: If you have some sort of method for perfectly identifying Pump and Dump schemes, it's possible you could make money if you time things right, but that timing is going to be very difficult to identify. Assuming you have no non-public material information, it should be perfectly legal. I suspect it's not a great idea for the reasons that Joe outlined, but it should be legal.
"Pay someone a fee to borrow their private Uber shares, then sell those private shares to someone else, then find someone else you can buy their private shares from for less than the net of the proceeds you made selling the borrowed shares you sold plus the fees you've paid to the first person and return your newly purchased shares back to the person you initially borrowed the shares from. On a serious note, Uber is private; there is no liquid public market for the shares so there is no mechanism to short the company.  The valuations you see might not even be legitimate because the company's financials are not public.  You could try to short a proxy for Uber but to my knowledge there is no public ""rideshare""/taxi service business similar enough to Uber to be a reasonably legitimate proxy." I believe that it's not possible for the public to know what shares are being exchanged as shorts because broker-dealers (not the exchanges) handle the shorting arrangements.  I don't think exchanges can even tell the difference between a person selling a share that belongs to her vs. a share that she's just borrowing.  (There are SEC regulations requiring some traders to declare that trades are shorts, but (a) I don't think this applies to all traders, (b) it only applies to the sells, and (c) this information isn't public.) That being said, you can view the short interest in a symbol using any of a number of tools, such as Nasdaq's here.  This is often cited as an indicator similar to what you proposed, though I don't know how helpful it would be from an intra-day perspective. you very well may know better than me, honestly; but with any volatile investment, it is necessarily hard to predict their intermediate term trends. that would be my only caution to you!  if you want speculative positions to hold, you might consider lower priced biopharms (though not pure penny positions). i made a bit of money on CCXI, for example. if you want more engagement/trading activity, consider tech trading or options (my personal favorite). im shorting stocks and gold.  the only way stocks and gold can go up is coz of QE3.   if no QE3, then im shorting gold and stocks.  but more gold than stocks.   and i'm holding cold hard US FIAT dollars in my mattress.    i'm letting my mattress manage my cash, nah' mean. I'm still short UVXY since a couple reverse splits ago, but I start to worry when everyone is shorting VIX, with VIX now under 10, and even VIX futures a few months out around 13. As far as VIX calls; I wouldn't play VIX options myself unless it's very near term (weeklies) and done as a quick trade at opportune times. This big trade however was an interesting approach. This is the bird's eye view of how shorting works: When you place an order to sell a stock short, your broker attempts to grab the desired number of shares from any accounts of its other customers and makes them available for you to sell. If no other customers own shares of this stock, then generally you are out of luck (It is more complicated like that in practice, but this is just an overview).    Your odds are better if the particular stock has a large float (i.e. a large number of shares that are actually available for trading) and its short ratio is low (which means relatively few shares   are currently being sold short). Also, a large brokerage may be more likely to have access to the shares than a small niche-market broker.   The example you've given, Angie's List (ANGI) is a $600M small-cap with a comparatively low float, and though I haven't been able to glean the short ratio, it appears that a lot of investors are bearish on this stock and probably already had the same idea to short it.  There is really no way to find out if a specific broker has shares in inventory available for shorting, short of (forgive the pun) checking directly with the broker. &gt; A short position also loses money if the stock just appreciates more slowly than the broader market, which is one way an overvaluation can correct itself.  Is there a derivative based on the literal second derivative (acceleration) of the stock price? If so, you'd be able to short those, yes? "There are a few things you are missing here. These appear to be penny stocks or subpenny stocks. Buying these are easy.... selling is a total different ball game. Buying commissions are low and selling commissions are outrageous. Another thing you are missing in this order is... some trading platform may assume the ""AON"" sale. That is All Or None. There was an offer of 10k shares @ .63. The buyer only wanted 10k what was the broker to do with the other 20k? Did you inform the broker that partial sales where acceptable? You may want to contact your broker and explain this to them. The ALL OR NONE order has made plenty of investor a little unhappy, which seems to be your new learning experience for the day. Sorry, school of hard knocks is not always fun." Most penny stocks go to zero because most businesses fail.  You stated in your original post that you were wondering specifically about companies with no assets. These are exactly the kind that fail and go to zero.  There are many holes within the regulatory structure that allow for many accounting tricks in penny stock land. And even in areas that are adequately regulated, there will be few to no remedies for the optimistic penny stock shareholder speculator. "Diversify into leveraged short/bear ETFs and then you can quit your job and yell at your boss ""F you I'm short your house!"" edit: this is a quote from Greg Lippmann and mentioned in the book ""The Big Short""" "First, I would like to use a better chart.  In my opinion, a close of day line chart obscures a lot of important information.  Here is a daily OHLC log chart:  The initial drop from the 1099.23 close on Oct 3 was to 839.8 intraday, to close at 899.22 on Oct 10.  After this the market was still very volatile and reached a low of 747.78 on Nov 20, closing only slightly higher than this.  It traded as high as 934.70 on Jan 6, 2009, but the whole period of Nov 24 - Feb 13 was somewhat of a trading range of roughly 800-900.  Despite this, the news reports of the time were frequently saying things like ""this isn't going to be a V shaped recovery, it is going to be U shaped.""  The roughly one week dip you see Feb 27 - Mar 9 taking it to an intraday low of 666.79 (only about 11% below the previous low) on first glance appears to be just a continuation of the previous trend.   However... The Mar 10 uptrend started with various news articles (such as this one) which I recall at the time suggested things like reinstating the parts of the Glass–Steagall Act of 1933 which had been repealed by the Gramm–Leach–Bliley Act.  Although these attempts appear to have been unsuccessful, the widespread telegraphing of such attempts in the media seemed to have reversed a common notion which I saw widespread on forums and other places that, ""we are going to be in this mess forever, the market has nowhere to go but down, and therefore shorting the market is a good idea now.""  I don't find the article itself, but one prominent theme was the ""up-tick"" rule on short selling: source From this viewpoint, then, that the last dip was driven not so much by a recognition that the economy was really in the toilet (as this really was discounted in the first drop and at least by late November had already been figured into the price).  Instead, it was sort of the opposite of a market top, where now you started seeing individual investors jump on the band-wagon and decide that now was the time for a foray into selling (short).  The fact that the up-tick rule was likely to be re-instated had a noticeable effect on halting the final slide." Gold's valuation is so stratospheric right now that I wonder if negative numbers (as in, you should short it) are acceptable in the short run.  In the long run I'd say the answer is zero.  The problem with gold is that its only major fundamental value is for making jewelry and the vast majority is just being hoarded in ways that can only be justified by the Greater Fool Theory.  In the long run gold shouldn't return more than inflation because a pile of gold creates no new wealth like the capital that stocks are a claim on and doesn't allow others to create new wealth like money lent via bonds.  It's also not an important and increasingly scarce resource for wealth creation in the global economy like oil and other more useful commodities are. I've halfway-thought about taking a short position in gold, though I haven't taken any position, short or long, in gold for the following reasons: Straight up short-selling of a gold ETF is too risky for me, given its potential for unlimited losses. Some other short strategy like an inverse ETF or put options is also risky, though less so, and ties up a lot of capital.  While I strongly believe such an investment would be profitable, I think the things that will likely rise when the flight-to-safety is over and gold comes back to Earth (mainly stocks, especially in the more beaten-down sectors of the economy) will be equally profitable with less risk than taking one of these positions in gold. "With debts exceeding assets by a billion dollars, this activity likely comes from penny stock speculators and ""pump and dump"" schemers. There is no rational expectation that the stock is even worth multiple pennies when the company is that far upside-down on its debts. Even if the debts could be restructured in a chapter 11, the equity shares would likely lose all of their value in the bankruptcy proceedings. Shareholders are at the bottom of the totem-pole when debts are being adjusted by the courts." Yeah I get that. But there are literally people who make a very good living by simply shorting small/micro caps that pop for no particular reason. Imagine if you shorted DCTH after it went from .05 to .31 Now it sits at .16 and will likely fall to .10 and under. Those are where the money making opportunities are now. Hit a home run on the way up and double your gains on the way back down. "Not necessarily. Shorting XOM is saying that EM (china + india) are going to have a ""slowdown"" (not neg growth but slower) and that US is going to pick up a lot slower.  Selling JNJ means the manager is overall bearish but doesn't have that much conviction (otherwise he would sell XOM or SPY), but still wants that negative exposure.  Personally, both are just plays on SPY with increased risk (XOM) or decreased risk (JNJ)."