Investments - Huge drop in bid price versus last close
Depends on when you are seeing these bids & asks-- off hours, many market makers pull their bid & ask prices entirely.  In a lightly traded stock there may just be no market except during the regular trading day.
"There are two distinct questions that may be of interest to you. Both questions are relevant for funds that need to buy or sell large orders that you are talking about. The answer depends on your order type and the current market state such as the level 2 order book. Suppose there are no iceberg or hidden orders and the order book (image courtesy of this question) currently is:  An unlimited (""at market"") buy order for 12,000 shares gets filled immediately: it gets 1,100 shares at 180.03 (1,100@180.03), 9,700 at 180.04 and 1,200 at 180.05. After this order, the lowest ask price becomes 180.05 and the highest bid is obviously still 180.02 (because the previous order was a 'market order'). A limited buy order for 12,000 shares with a price limit of 180.04 gets the first two fills just like the market order: 1,100 shares at 180.03 and 9,700 at 180.04. However, the remainder of the order will establish a new bid price level for 1,200 shares at 180.04. It is possible to enter an unlimited buy order that exhausts the book. However, such a trade would often be considered a mis-trade and either (i) be cancelled by the broker, (ii) be cancelled or undone by the exchange, or (iii) hit the maximum price move a stock is allowed per day (""limit up""). Funds and banks often have to buy or sell large quantities, just like you have described. However they usually do not punch through order book levels as I described before. Instead they would spread out the order over time and buy a smaller quantity several times throughout the day. Simple algorithms attempt to get a price close to the time-weighted average price (TWAP) or volume-weighted average price (VWAP) and would buy a smaller amount every N minutes. Despite splitting the order into smaller pieces the price usually moves against the trader for many reasons. There are many models to estimate the market impact of an order before executing it and many brokers have their own model, for example Deutsche Bank. There is considerable research on ""market impact"" if you are interested. I understand the general principal that when significant buy orders   comes in relative to the sell orders price goes up and when a   significant sell order comes in relative to buy orders it goes down. I consider this statement wrong or at least misleading. First, stocks can jump in price without or with very little volume. Consider a company that releases a negative earnings surprise over night. On the next day the stock may open 20% lower without any orders having matched for any price in between. The price moved because the perception of the stocks value changed, not because of buy or sell pressure. Second, buy and sell pressure have an effect on the price because of the underlying reason, and not necessarily/only because of the mechanics of the market. Assume you were prepared to sell HyperNanoTech stock, but suddenly there's a lot of buzz and your colleagues are talking about buying it. Would you still sell it for the same price? I wouldn't. I would try to find out how much they are prepared to buy it for. In other words, buy pressure can be the consequence of successful marketing of the stock and the marketing buzz is what changes the price." You said the decision will be made by EOD. If you've made the decision prior to the market close, I'd execute on the closing price.  If you are trading stocks with any decent volume, I'd not worry about the liquidity.  If your strategy's profits are so small that your gains are significantly impacted by say, the bid/ask spread (a penny or less for liquid stocks) I'd rethink the approach. You'll find the difference between the market open and prior night close is far greater than the normal bid/ask. Just before a crash or at the start of the crash most of the smart money would have gotten out, the remaining technical traders would be out by the time the market has dropped 10 to 15%, and some of them would be shorting their positions by now.  Most long-term buy and hold investors would stick to their guns and stay in for the long haul. Some will start to get nervous and have sleepless nights when the markets have fallen 30%+ and look to get out as well. Others stay in until they cannot stand it anymore. And some will stick it out throughout the downturn. So who are the buyers at this stage? Some are the so called bargain hunters that buy when the market has fallen over 30% (only to sell again when it falls another 20%), or maybe buy more (because they think they are dollar cost averaging and will make a packet when the price goes back up - if and when it does). Some are those with stops covering their short positions, whilst others may be fund managers and individuals looking to rebalance their portfolios. What you have to remember during both an uptrend and a downtrend the price does not move straight up or straight down. If we take the downtrend for instance, it will have lower lows and lower highs (that is the definition of a downtrend). See the chart below of the S&P 500 during the GFC falls.  As you can see just before it really started falling in Jan 08 there was ample opportunity for the smart money and the technical traders to get out of the market as the price drops below the 200 MA and it fails to make a higher peak. As the price falls from Jan 08 to Mar 08 you suddenly start getting some movement upwards. This is the bargain hunters who come into the market thinking the price is a bargain compared to 3 months ago, so they start buying and pushing the price up somewhat for a couple of months before it starts falling again. The reason it falls again is because the people who wanted to sell at the start of the year missed the boat, so are taking the opportunity to sell now that the prices have increased a bit. So you get this battle between the buyers (bulls) and seller (bears), and of course the bears are winning during this downtrend. That is why you see more sharper falls between Aug to Oct 08, and it continues until the lows of Mar 09. In short it has got to do with the phycology of the markets and how people's emotions can make them buy and/or sell at the wrong times. The reality that the share price did not move shows that there is nothing nefarious going on.  It is most likely some mutual fund offloading their position to another fund.   You can commonly see the play out at market openings if you have access to level II data.  You will see a big block sitting on both sides of the same bid/ask.  If you put in a higher bid (or vice versa) the two positions will move to match yours.  And when the market opens their trade will be transacted BEFORE yours, even though you are thinking ... 'well I put in my bid first'.  Obviously they have agreed to swap and agreed to use whatever value the market decides. Simple Schwaab does not have actually your securities they have leased them out and have to borrow them back. all assets are linked with derivatives now. They show on the balance sheet but have to be untangled. Thats why the market drops disproportionally fast to the actual number of shares sold. This sometimes happens to me. It depends on how liquid the option is. Normally what I see happening is that the order book mutates itself around my order. I interpret this to mean that the order book is primarily market makers. They see a retail investor (me) come in and, since they don't have any interest in this illiquid option, they back off. Some other retail investor (or whatever) steps in with a market order, and we get matched up. I get a fill because I become the market maker for a brief while. On highly liquid options, buy limits at the bid tend to get swallowed because the market makers are working the spread. With very small orders (a contract or two) on very liquid options, I've had luck getting quick fills in the middle of the spread, which I attribute to MM's rebalancing their holdings on the cheap, although sometimes I like to think there's some other anal-retentive like me out there that hates to see such a lopsided book. :) I haven't noticed any particular tendency for this to happen more with puts or calls, or with buy vs sell transactions. For a while I had a suspicion that this was happening with strikes where IV didn't match IV of other strikes, but I never cared enough to chase it down as it was a minor part of my overall P/L. "I can think of the following situations in which one could see a trade occur between the visible best bid & offer: 1) on a public exchange, people have posted hidden limit orders with either bid prices above the best visible bid or offers below the best visible offer, and incoming orders have executed against this hidden liquidity[1]; 2) some orders may have been matched in dark pools which offer ""mid-point matching"" where buy and sell orders are matched using the mid-point of the best available publicly posted bid and offer as the reference price, and which executed trades are then reported to the public markets; or 3) some internalising broker has traded off exchange directly with a client and is now reporting the trade to the public as is often required. Now how exactly any of the above situations indicates that a ""trend is about to come to an end"", I do not know. [1] Exchanges often match orders on a price/visibility/time basis, whereby the orders are prioritised by price (better prices get to trade first), then by visibility (visible orders get to trade first) then by time (first come, first serve)." There could also be some degree of dilution at play here. If they are rapidly expanding and hiring, or if they took on another round of funding each share may have a lower amount of value though the company might be worth more than they were previously. The newly issued options may also be of a different class. This happens on dark pools quite often. If I am a large institutional investor with tens of millions of shares, I may want to unload slowly and limit the adverse affects on the price of the stock. Dark pools offer anonymity and have buyers / sellers that can handle large volume.  In the case of a day trader, they often trade stocks with light volume (since they have large fluctuations that can be quite profitable throughout the session). At the end of the session, many traders are unwilling to hold positions on margin and want to unload fast. "IMO, what it seems like you've done is nothing more than having screened out a company worth further investigation. The next step would be a thorough analysis of the company's past financials and current statements to arrive at your own opinion / forecast of the immediate and far future of the company's prospects.  Typically, this is done by looking at the company's regulatory filings, and maybe some additional searching on comparison businesses.  There are many sources of instruction for how one might ""value"" or ""analyze"" a company, or that provide help on ""reading a balance sheet"".  (This is not an easy skill to learn, but it is one that will prove invaluable over a lifetime of investing.) It is possible that you'll uncover a deteriorating business where the latest selling, and subsequent drop in price that caused the high yield, is well-deserved.  In which case, you know to stay away and move on to the next idea. On the other hand, you might end up confident that the company is not suffering from a drop in sales, rise in expenses, growing debt payments, loss of ""moat"", etc.  In which case, you've found a great investment candidate.  I say candidate because you still may decide this company isn't for you, even if the financials are right, because you might find better opportunities for an equal, or acceptable, return at lower risk while you're researching. As to the yield being high when there are no problems with the fundamentals of the business, this may simply be because of panic selling during this past few week's downturn, or some other sort of temporary and superficial scare.  However, be warned that the masses can remain irrational, and thus the price stay suppressed or even drop further, for longer than you're willing to wait for your ROI.  The good news is that in that case, you're being well compensated to wait at a 11+% yield!" I asked a friend and he gave me a good explanation, so I'm just gonna paste it here for others: There is a simple and a complex answer depending on how much you want to understand the pricing dynamic of options.  LEAPs don't react 1:1 with a stock move because the probability of your option being in the money at expiry is still very much up in the air so you basically don't get full credit for a move in the stock this far out from expiry. The more complex answer involves a discussion of option 'greeks'.  Delta, Gamma, Theta, Vega, and Rho are variables that affect the pricing of all options.  The key greek in this case is Delta because it describes mathematically the expected move of an option as a ratio vs changes in stock price.  For put options the ratio is -1 to 0 where -1 is direct correlation between stock price and option price and 0 is no correlation.  The Delta increases as an option gets deeper in the money and also as it gets closer to expiry and reflects the probability of the option expiring in the money.  For your option contract the current Delta is -0.5673  so -3.38 * -0.5673 = 1.9 which is close.  Also keep in mind that that strike price had a last trade at 12:03 when the stock was at 13.3 and the current ask price is 22.30 so the last price isn't a true reflection of the market value.   As for the other greeks, Gamma is a reflection of volatility in the sense that it affects the rate of change of Delta as price and time changes.  Theta is the value of the time component of the option and is expressed as the expected time decay per day.  The problem is that the time premium is really some arbitrary number that the market maker seems to be able to change at will without justification and it can fluctuate wildly over short periods of time and I think this may explain some of the discrepancy.   If you bought the options when AAPL was $118.68 a couple weeks ago (option price of $18.85) and now AAPL is at $112.34 and the Delta over that time averaged at -0.55 then your expected option price would be $22.34 (($118.68 - $112.34) * 0.55 + 18.85 = $22.34) so you lost around $0.24 in time premium or 'Theta burn' over the last 2 weeks assuming it opens trading around 22.1 on Monday. Your broker should have information about the option contract greeks somewhere.  For my platform I have to put the cursor over top of the option contract for it to show me the greeks.  If your broker doesn't have this then you can get it from nasdaq.com. This is another reason that I only invest in deep in the money LEAPs because the time premium is much much lower than near the money and also because delta is much higher so if I want to trade out of it early I don't feel like I'm getting ripped off not getting paid for a stock price move.  For example look at the Jan 17 175 put.  The Delta is -0.9 and the time premium is only $0-1 depending if you are looking at the bid or ask.  The only downside is expected returns are lower for deep in the money contracts and they are expensive to buy. There are 2 approaches. One of them is already mentioned by @Afforess. If the approach by @Afforess is not feasible, and you can not see yourself making an unbiased decision, close the position.  By closing the position you will not get the best price. But by removing a distraction you will reduce amount of mistakes you make in the other stocks. Like @chirs, I'm of the opinion that you might want to buy more. I've done this a couple of times, price dropped a bunch, and I said, heck, I bought some last week, and this week I can get twice as much stock for about the same price. Brought down my average cost per share, and when the company was taken private, I actually didn't lose money - unlike some other people I know, who only bought at one price, watched the drop, and held on awaiting a recovery (which didn't happen in time before the big money swooped in on it). But to do this, you need to keep cash reserves (that, like @afforess says, you can afford to lose all of) on hand, awaiting buying opportunities.  This, too, is a cost - an opportunity cost. "Firstly, if a stock costs $50 this second, the bid/ask would have to be 49/50.  If the bid/ask were 49/51, the stock would cost $51 this second.  What you're likely referring to is the last trade, not the cost.  The last trading price is history and doesn't apply to future transactions. To make it simple, let's define a simple order book.  Say there is a bid to buy 100 at $49, 200 at $48, 500 at $47.  If you place a market order to sell 100 shares, it should all get filled at $49.  If you had placed a market order to sell 200 shares instead, half should get filled at $49 and half at $48.  This is, of course, assuming no one else places an order before you get yours submitted.  If someone beats you to the 100 share lot, then your order could get filled at lower than what you thought you'd get.  If your internet connection is slow or there is a lot of latency in the data from the exchange, then things like this could happen.  Also, there are many ECNs in addition to the exchanges which may have different order books.  There are also trades which, for some reason, get delayed and show up later in the ""time and sales"" window. But to answer the question of why someone would want to sell low... the only reason I could think is they desire to drive the price down." "This summer I used a loan from my 401(k) to help pay for the down payment of a new house. We planned on selling a Condo a few months later, so we only needed the loan for a short period but wanted to keep monthly payments low since we would be paying two mortgages for a few months. I also felt like the market might take a dip in the future, so I liked the idea of trying to cash out high and buy back low (spoiler alert: this didn't happen). So in July 2017 I withdrew $17,000 from my account (Technically $16,850.00 principal and $150 processing fee) at an effective 4.19% APR (4% rate and then the fee), with 240 scheduled payments of $86.00 (2 per month for 10 years). Over the lifetime of the loan the total finance charge was $3,790, but that money would be paid back into my account. I was happy with the terms, and it helped tide things over until the condo was sold a few months later. But then I decided to change jobs, and ended up having to pay back the loan ~20 weeks after it was issued (using the proceeds from the sale of the condo). During this time the market had done well, so when I paid back the funds the net difference in shares that I now owned (including shares purchased with the interest payments) was $538.25 less than today's value of the original count of shares that were sold to fund the loan. Combined with the $150 fee, the overall ""cost"" of the 20 week loan was about 4.05%. That isn't the interest rate (interest was paid back to my account balance), but the value lost due to the principal having been withdrawn. On paper, my account would be worth that much more if I hadn't withdrawn the money. Now if you extrapolate the current market return into 52 weeks, you can think of that loan having an APR ""cost"" of around 10.5% (Probably not valid for a multi year calculation, but seems accurate for a 12 month projection). Again, that is not interest paid back to the account, but instead the value lost due to the money not being in the account. Sure, the market could take a dip and I may be able to buy the shares back at a reduced cost, but that would require keeping sizable liquid assets around and trying to time the market. It also is not something you can really schedule very well, as the loan took 6 days to fund (not including another week of clarifying questions back/forth before that) and 10 day to repay (from the time I initiated the paperwork to when the check was cashed and shares repurchased). So in my experience, the true cost of the loan greatly depends on how the market does, and if you have the ability to pay back the loan it probably is worth doing so. Especially since you may be forced to do so at any time if you change jobs or your employment is terminated."