How to execute a large stock purchase, relative to the order book?
What is the average daily volume traded? It looks like this stock may have a liquidity problem. If that is the case I would not buy this stock at all as you may have the same problem when you try to sell it. Generally try to stay away from illiquid stocks, if your order size is more than 10% of the average daily volume traded, then don't buy it.  I usually stay away from stocks with an average daily volume of less than 100,000. I am able to place an 'all or none' order with my broker. But doing so reduces the number of potential sources to fulfill the order. As others have mentioned, try a limit order to get a specific price. I normally just do a buy limit at the price I want to buy it at. Then it executes when it's that price or lower, but there's still a chance you might purchase some shares at a larger price. But since we're small fry and using brokerages, there's not much we can do about it.
To answer your question in its entirety there's more information we need (exchange, session, traded security, order type, etc.). Most exchanges support partial fills, that is your order will be partially executed and modified.  In your example, you'd get an execution of 10 shares at $100, and your order ticket will be modified to $100 for 990 shares. Like John Bensin explained, there are ways to prevent partial filling through order modifiers (e.g. Fill-or-Kill). My addition here is, there are also ways to prevent the other bit, i.e. do the partial fill but don't keep a modified order in the system.  You'd have to mark the order Immediate-or-Cancel (IoC).  In your case you'd be partially filled (10 @$100) and that's it.  For the remaining 990 shares you'd have to enter a new order. No, this isn't possible, especially not when you're trading a highly liquid stock like Apple. When you put in your buy order at $210, any other traders that have open limit sell orders with the correct parameters, e.g. price and volume, will have their order(s) filled. This will occur before you can put in your own sell order and purchase your own shares because the other orders are listed on the order book first. In the US, many tax-sheltered accounts like IRA's have specific rules against self-dealing, which includes buying and selling assets with yourself, so such a transaction would be prohibited by definition. Although I'm not entirely sure if this applies to stocks, the limitation described in the first paragraph still applies regardless. If this were possible, rest assured that high-frequency traders would take advantage of this tactic to manipulate share prices. (I've heard critics say that this does occur, but I haven't researched it myself or seen any data about it) "Yes! What you are describing is an ""off-exchange"" trade and can be done using stock certificates. Here, you will privately negotiate with the seller on a price and delivery details. That is the old-school way to do it. Many companies (about 20% of the S&P 500) will not issue paper certificates and you may run a hefty printing fee up to $500 (source: Wikipedia, above). Other other type of private-party transactions include a deal negotiated between two parties and settled immediately or based on a future event. For example, Warren Buffet created a deal with Goldman Sachs where Warren would have the choice to purchase GS shares in the future at a certain price. This was to be settled with actual shares (rather than cash-settled). Ignoring that he later canceled this agreement, if it were to go through the transaction would still have been handled by a broker transferring the shares. You can purchase directly from a company using a direct stock purchase plan (SPP). Just pick up the phone, ask for their investor relations and then ask if they offer this option. If not, they will be glad for your interest and look into setting it up for you." "I would think that a lot of brokers would put the restriction suggested in @homer150mw in place or something more restrictive, so that's the first line of answer. If you did get assigned on your short option, then (I think) the T+3 settlement rules would matter for you.  Basically you have 3 days to deliver.  You'll get a note from your broker demanding that you provide the stock and probably threatening to liquidate assets in your account to cover their costs if you don't comply.  If you still have the long-leg of the calendar spread then you can obtain the stock by exercising your long call, or, if you have sufficient funds available, you can just buy the stock and keep your long call.  (If you're planning to exercise the long call to cover the position, then you need to check with your broker to see how quickly the stock so-obtained will get credited to your account since it also has some settlement timeline.  It's possible that you may not be able to get the stock quickly enough, especially if you act on day 3.) Note that this is why you must buy the call with the far date.  It is your ""insurance"" against a big move against you and getting assigned on your short call at a price that you cannot cover. With the IRA, you have some additional concerns over regular cash account - Namely you cannot freely contribute new cash any time that you want.  That means that you have to have some coherent strategy in place here that ensures you can cover your obligations no matter what scenario unfolds.  Usually brokers put additional restrictions on trades within IRAs just for this reason. Finally, in the cash account and assuming that you are assigned on your short call, you could potentially could get hit with a good faith, cash liquidation, or free riding violation when your short call is assigned, depending on how you deliver the stock and other things that you're doing in the same account.  There are other questions on that on this site and lots of information online.  The rules aren't super-simple, so I won't try to reproduce them here.  Some related questions to those rules: An external reference also on potential violations in a cash account: https://www.fidelity.com/learning-center/trading-investing/trading/avoiding-cash-trading-violations" TD will only sell the stock for you if there's a buyer. There was a buyer, for at least one transaction of at least one stock at 96.66. But who said there were more? Obviously, the stocks later fell, i.e.: there were not that many buyers as there were sellers. What I'm saying is that once the stock passed/reached the limit, the order becomes an active order. But it doesn't become the only active order. It is added to the list, and to the bottom of that list. Obviously, in this case, there were not enough buyers to go through the whole list and get to your order, and since it was a limit order - it would only execute with the limit price you put. Once the price went down you got out of luck.  That said, there could of course be a possibility of a system failure. But given the story of the market behavior - it just looks like you miscalculated and lost on a bet. Assuming that blocks, dark liquidity, and auctions aren't available, one of the biggest things that equity traders also have going for them is the availability of different execution venues, as well as the aforementioned ability to strategically time execution/child order placement based on the state of the order book at any given time.  A security with a NYSE primary listing (BAC or IBM for example) will be traded on several exchanges/ECNs - Nasdaq, NYSE Arca, the various Bats exchanges - and that in itself opens up a lot of opportunity to spread out an order.  As an alternative to simply going through several price levels on a single exchange, you can also route out multiple orders simultaneously to different exchanges to scoop up liquidity.  All of that being said, I think it should be noted that you really can't exclude the execution methods that you mentioned in your original question.  Any large institutional investor looking to trade in size will only get so far with trading on lit venues especially in the US equity marketplace.  Taking advantage of block liquidity/IOIs or floating part or all of an order in a dark pool is a good way to mask intentions and minimize market impact.  If you're part of a beta/index tracking strategy, you actually need to leverage auctions (index rebalances, like the MSCI, Russell, S&amp;P all have a ton of participants executing market on close orders to account for adds/deletes/reweights).    Overall, the buy side is becoming increasingly sophisticated when it comes to advanced execution, and it has been interesting to see how fintech companies, brokers, and exchanges have been feeding into the innovation. "if it opens below my limit order  What exactly are you trying to achieve here? If your limit order is for 100 and the stock opens ""below"" your limit order, say 99, then it is obviously going to buy it automatically.  also place a stop loss on the same order  Most brokers allow limit + stop loss order at the same time on same order.  What I conclude from your question is that you're with a broker that is using obscure technology. Get a better broker or maybe, retry phrasing your question correctly." You are better off just placing a market order if you want to buy or sell straight away and avoid the queues. A market order will guarantee the purchase or sale of your shares, but it won't guarantee the price. My broker collates the order book by price and marketplace, displaying the number of shares available at each level, sorted as in Victor's screencap. You can glean information from not just a snapshot of the order book but also by watching how it changes over time. Although it's not always a complete picture -- many brokers hold limit orders internally until the market is close, at which point they'll route to an exchange or trade internally. And of course skilled market participants know that there's people out there looking to glean information from the order book and will act to confuse the picture. The order book can show you: Combined with a list of trades (price & size, and whether it was a buy or sell), you can get a much more complete picture of what's going on with a stock than by looking at charts alone. That is mostly true, in most situations when there are more buy orders than sell orders (higher buy volume orders than sell volume orders), the price will generally move upwards and vice versa, when there are more sell orders than buy orders (higher sell volume orders than buy volume orders), the price will generally move downwards. Note that this does not always happen, but usually it does. You are also correct that for a trade to take place a buyer has to be matched with a seller (or the buy volume matched with the sell volume). But not all orders get executed as trades. Say there are 50 buy orders in the order book with a total volume of 100,000 shares and the highest buy order is currently at $10.00. On the other side there are only 10 sell orders in the order book with total volume of 10,000 shares and the lowest sell order is currently $10.05. At the moment there won't be a trade unless a new buyer or seller enters the market to match the opposing side, or an existing order gets amended upper or lower to match the opposing side. With more demand than supply in the order books what will be the most likely direction that this stock moves in? Most likely the price will move upwards. If a new buyer sees the price moving higher and then looks at the market depth, they would most likely place an order closer to the lowest sell order than the current highest buy order, say $10.01, to be first in line in case a market sell order is placed on the market. As new buy orders enter the market it drives the price higher and higher until the buy orders dry up. What happened here is pretty obvious: You were trying to sell 2000 shares and apparently didn't mark your order to permit partial execution.  While they had a buyer at 94.66 they didn't want 2000 shares.  Thus your order went unfilled. I have had this happen a couple of times because of splits or sales of portions of the company.  The general timeline was to announce how the split was to be handled; then the split; then a freeze in purchasing stock in the other company; then a freeze in sales; followed by a short blackout period; then the final transfers to funds/options/cash based on a mapping announced at the start of the process. You need to answer two questions: To determine if the final transactions will make the market move you have to understand how many shares are involved compared to the typical daily volume. There are two caveats: professional investors will be aware of the transaction date and can either ignore the employee transactions or try and take advantage of them; There may also be a mirroring set of transactions if the people left in the old company were awarded shares in your company as part of the sale. If you are happy with the default mapping then you can do nothing, and let the transaction happen based on the announced timeline. It is easy, and you don't have to worry about deadlines. If you don't like the default mapping then you need to know when the blackout period starts, so you don't end up not being able to perform the steps you want when you want.  Timing is up to you. If the market doesn't like the acquisition/split it make make sense to make the move now, or wait until the last possible day depending on which part they don't like. Only you can answer that question. "If there are no limit orders on the opposite side of the book when your market order gets its turn for execution, it should be rejected by the market.  A market order should generally not ""sit on the book"" like your question suggests waiting for another order to arrive.  Thus, the situation that you describe should not happen in an ordinary market that is operating in an orderly fashion. This is not to say that your order cannot ""sit"" for a while in a queue - If there is heavy volume, orders will be executed in order, so your your market order may have to wait for orders entered ahead of it to be processed.  But once its turn comes up, that's it. There are some related points to consider: I should caution that my answer is biased a bit to US stock markets, whereas you asked about currency markets.  I believe the same basic principles apply, but I'd be swayed by someone with evidence to the contrary.  I'd also note that currency tends to be more liquid than stock, so I think it's less likely that this situation would come up.  Maybe possible for a ""weak"" currency or a currency that experiences a sudden crisis of some sort." "Alternatively you could exercise 12000 shares for $36000 and immediately sell 7200 shares to recover your exercise price. Then you use the remaining 4800 share to pay the exercise price of the remaining 8000 options. Both scenarios are equivalent but may have different fees associated, so it's worth checking the fine print.  Tax wise: The above example is ""cash neutral before taxes"". The taxes associated with these transaction are substantial, so it's highly recommended to talk with a tax adviser. ""cash neutral after taxes"" depends highly on your specific tax situation." A few observations - A limit order can certainly work, as you've seen.  I've put in such an order far beyond the true value, and gotten back a realistic bid/ask within 10 minutes or so. That at least gave me an idea where to set my limit.  When this doesn't work, an exercise is always another way to go. You'll get the full intrinsic value, but no time value, by definition.  Per your request in comment - You own a put, strike price $100. The stock (or ETF) is trading at $50. You buy the stock and tell the broker to exercise the put, i.e. deliver the stock to the buyer of the put.