Can I participate in trading Facebook shares on their IPO day from any brokerage?
Any retail equity brokerage will give you access to the NYSE, and thus Facebook shares as they become available.  However, it is important to note that you nor any retail investor will be able to purchase FB at the IPO prices ($33-38 IIRC).  The only people who will be able to buy in at that price are the underwriting investment banks and major investors who have subscribed to the IPO.  You, and all the other retail investors will only be able to buy in as those major investors offer shares on the secondary market.   This being Facebook, there will probably be a significant premium over the IPO price, both due to demand and systemic underpricing of IPOs to encourage the opening 'pop'.   So, if you're intent on buying in at the IPO, pay close attention as the date approaches.  Look at how the recent big IPOs have performed (GRPN, LNKD come to mind).  Know how much you're willing to commit and what price you want.  However, no one is going to know what the opening market price will be come Friday morning.  Be watching your financial data source / analysis of choice and be prepared to make a judgement. Yes. The real question is whether you should. You should consider your investment options, and take into the account that there's much more hype than value in many companies. By definition, an IPO'd stock is publicly traded, and you can buy shares if you wish. There's often an excitement on the first day that doesn't carry over to the next days or weeks.  The opening price may be well above the IPO price, depending on that demand.
I think George's answer explains fairly well why the brokerages don't allow this - it's not an exchange rule, it's just that the brokerage has to have the shares to lend, and normally those shares come from people's margin, which is impossible on a non-marginable stock. To address the question of what the alternatives are, on popular stocks like SIRI, a deep In-The-Money put is a fairly accurate emulation of an actual short interest.  If you look at the options on SIRI you will see that a $3 (or higher) put has a delta of -$1, which is the same delta as an actual short share. You also don't have to worry about problems like margin calls when buying options.  The only thing you have to worry about is the expiration date, which isn't generally a major issue if you're buying in-the-money options... unless you're very wrong about the direction of the stock, in which case you could lose everything, but that's always a risk with penny stocks no matter how you trade them. At least with a put option, the maximum amount you can lose is whatever you spent on the contract.  With a short sale, a bull rush on the stock could potentially wipe out your entire margin.  That's why, when betting on downward motion in a microcap or penny stock, I actually prefer to use options.  Just be aware that option contracts can generally only move in increments of $0.05, and that your brokerage will probably impose a bid-ask spread of up to $0.10, so the share price has to move down at least 10 cents (or 10% on a roughly $1 stock like SIRI) for you to just break even; definitely don't attempt to use this as a day-trading tool and go for longer expirations if you can. When a company IPOs the underwriters sell a given percentage on IPO day and shortly thereafter. Whatever is sold on IPO day trades freely.   Insiders, employees and investors who bought before the IPO only sell a percentage of their shares on IPO day. They all also agree to 'lock up' the remainder for a period of time, so that not everyone is rushing to the exits right away. Well, if you're an employee you don't per-se agree, it's just how your stock options are setup and you don't really have a say in the matter. "If anything, the price of an ETF is more tightly coupled to the underlying holdings or assets than a mutual fund, because of the independent creation/destruction mechanism. With a mutual fund, the price is generally set once at the end of each day, and the mutual fund manager has to deal with investments and redemptions at that price. By the time they get to buying or selling the underlying assets, the market may have moved or they may even move the market with those transactions. With an ETF, investment and redemption is handled by independent ""authorized participants"". They can create new units of the ETF by buying up the underlying assets and delivering them to the ETF manager, and vice versa they can cancel units by requesting the underlying assets from the ETF manager. ETFs trade intraday (i.e. at any time during trading hours) and any time the price diverges too far from the underlying assets, one of the authorized participants has an incentive to make a small profit by creating or destroying units of the ETF, also intraday." "First, what structure does your index fund have?  If it is an open-end mutual fund, there are no bid/ask spread as the structure of this security is that it is priced once a day and transactions are done with that price.  If it is an exchange-traded fund, then the question becomes how well are authorized participants taking advantage of the spread to make the fund track the index well?  This is where you have to get into the Creation and Redemption unit construct of the exchange-traded fund where there are ""in-kind"" transactions done to either create new shares of the fund or redeem out shares of the fund.  In either case, you are making some serious assumptions about the structure of the fund that don't make sense given how these are built. Index funds have lower expense ratios and are thus cheaper than other mutual funds that may take on more costs.  If you want suggested reading on this, look at the investing books of John C. Bogle who studied some of this rather extensively, in addition to being one of the first to create an index fund that became known as ""Bogle's Folly,"" where a couple of key ones would be ""Common Sense on Mutual Funds: New Imperatives for the Intelligent Investor"" and ""Bogle on Mutual Funds: New Perspectives for the Intelligent Investor."" In the case of an open-end fund, there has to be a portion of the fund in cash to handle transaction costs of running the fund as there are management fees to come from running the fund in addition to dividends from the stocks that have to be carefully re-invested and other matters that make this quite easy to note.  Vanguard 500 Index Investor portfolio(VFINX) has .38% in cash as an example here where you could look at any open-end mutual fund's portfolio and notice that there may well be some in cash as part of how the fund is managed.  It’s the Execution, Stupid would be one of a few articles that looks at the idea of ""tracking error"" or how well does an index fund actually track the index where it can be noted that in some cases, there can be a little bit of active management in the fund. Just as a minor side note, when I lived in the US I did invest in index funds and found them to be a good investment.  I'd still recommend them though I'd argue that while some want to see these as really simple investments, there can be details that make them quite interesting to my mind. How is its price set then? The price is computed by taking the sum value of all the assets of the fund minus the liabilities and divided by the number of outstanding shares.  The price of the assets would include the closing price on the stock rather than a bid or ask, similar pricing for bonds held by the fund, derivatives and cash equivalents.  Similarly, the liabilities would be costs a fund has to pay that may not have been paid yet such as management fees, brokerage costs, etc. Is it a weighted average of all the underlying stock spreads, or does   it stand on its own and stems from the usual supply & demand laws ? There isn't any spread used in determining the ""Net Asset Value"" for the fund.  The fund prices are determined after the market is closed and so a closing price can be used for stocks. The liabilities could include the costs to run the fund as part of the accounting in the fund, that most items have to come down to either being an asset, something with a positive value, or a liability, something with a negative value. Something to consider also is the size of the fund.  With over $7,000,000,000 in assets, a .01% amount is still $700,000 which is quite a large amount in some ways." First thing to consider is that getting your hands on an IPO is very difficult unless you have some serious clout. This might help a bit in that department (http://www.sec.gov/answers/ipoelig.htm) However, assuming you accept all that risk and requirements, YES - you can buy stocks of any kind in the US even if you are a foreigner. There are no laws prohibiting investment/buying in the US stock market. What you need is to get an online trading account from a registered brokerage house in the US. Once you are registered, you can buy whatever that is offered. &gt; I wish I had sufficient funds to open a brokerage account at FB's IPO. I wanted to shortsell the stock with every fiber of my being once I saw that imaginary $38 price valuation.  It would've been impossible anyways, no shares were available. It took me over a week to find some shares to short ( at $29.50 ) 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) "TDAmeritrade, an online stock broker, provides banking services within their brokerage accounts. The service offers all of what you are looking for. HOWEVER, this service is only available for free with their ""Apex"" qualification.  Here is a tariff of their fees and services."