Understanding Put Options
Options, both puts and calls, are typically written/sold at different strike prices. For example, even though the stock of XYZ is currently trading at $12.50, there could be put options for prices ranging from $0.50 to $30.00, just as an example. There are several factors that go into determining the strike prices at which people are willing to write options. The writer/seller of an option is the person on the other side of the trade that has the opposite opinion of you. If you are interested in purchasing a put on a stock to hedge your downside, that means the writer/seller of the put is betting that you are wrong and that the stock price will rise instead.
"Don't put money in things that you don't understand. ETFs won't kill you, ignorance will. The leveraged ultra long/short ETFs hold swaps that are essentially bets on the daily performance of the market. There is no guarantee that they will perform as designed at all, and they frequently do not. IIRC, in most cases, you shouldn't even be holding these things overnight. There aren't any hidden fees, but derivative risk can wipe out portions of the portfolio, and since the main ""asset"" in an ultra long/short ETF are swaps, you're also subject to counterparty risk -- if the investment bank the fund made its bet with cannot meet it's obligation, you're  may lost alot of money. You need to read the prospectus carefully. The propectus re: strategy. The Fund seeks daily investment results, before fees and expenses, that correspond to twice the inverse (-2x) of the daily performance of the Index. The Fund does not seek to achieve its stated investment objective over a period of time greater than a single day. The prospectus re: risk. Because of daily rebalancing and the compounding of each day’s return over time, the return of the Fund for periods longer than a single day will be the result of each day’s returns compounded over the period, which will very likely differ from twice the inverse (-2x) of the return of the Index over the same period. A Fund will lose money if the Index performance is flat over time, and it is possible that the Fund will lose money over time even if the Index’s performance decreases, as a result of daily rebalancing, the Index’s volatility and the effects of compounding. See “Principal Risks” If you want to hedge your investments over a longer period of time, you should look at more traditional strategies, like options. If you don't have the money to make an option strategy work, you probably can't afford to speculate with leveraged ETFs either." 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. Put options are basically this. Buying a put option gives you the right but not the obligation to sell the underlying security at a certain date for a fixed price, no matter its current market value at that time. However, markets are largely effective, and the price of put options is such that if you bought them to cover you the whole time, you would on average pay more than you'd gain from the underlying security. There is no such thing as a risk-free investment. Yes When exercising a stock option you will be buying the stock at the strike price so you will be putting up your money, if you lose that money you can declare it as a loss like any other transaction. So if the stock is worth $1 and you have 10 options with a strike at $0.50 you will spend $500 when you exercise your options. If you hold those shares and the company is then worth $0 you lost $500. I have not verified my answer so this is solely from my understanding of accounting and finance. Please verify with your accountant to be sure. "Cart's answer describes well one aspects of puts: protective puts; which means using puts as insurance against a decline in the price of shares that you own.  That's a popular use of puts.  But I think the wording of your question is angling for another strategy: Writing puts. Consider: Cart's strategy refers to the buyer of a put.  But, on the transaction's other side is a seller of the put – and ultimately somebody created or wrote that put contract in the first place!  That first seller of the put – that is, the seller that isn't just selling one they themselves bought – is the put writer. When you write a put, you are taking on the obligation to buy the other side's stock at the put exercise price if the stock price falls below that exercise price by the expiry date.  For taking on the obligation, you receive a premium, like how an insurance company charges a premium to insure against a loss. Example:  Imagine ABC Co. stock is trading at $25.00.  You write a put contract agreeing to buy 100 shares of ABC at $20.00 per share (the exercise price) by a given expiration date.  Say you receive $2.00/share premium from the put buyer.  You now have the obligation to purchase the shares from the put buyer in the event they are below $20.00 per share when the option expires – or, technically any time before then, if the buyer chooses to exercise the option early. Assuming no early assignment, one of two things will happen at the option expiration date: ABC trades at or above $20.00 per share. In this case, the put option will expire worthless in the hands of the put buyer.  You will have pocketed the $200 and be absolved from your obligation.  This case, where ABC trades above the exercise price, is the maximum profit potential. ABC trades below $20.00 per share.  In this case, the put option will be assigned and you'll need to fork over $2000 to the put buyer in exchange for his 100 ABC shares.  If those shares are worth less than $18.00 in the market, then you've suffered a loss to the extent they are below that price (times 100), because remember – you pocketed $200 premium in the first place.  If the shares are between $18.00 to $20.00, you're still profitable, but not to the full extent of the premium received. You can see that by having written a put it's possible to acquire ABC stock at a price lower than the market price – because you received some premium in the process of writing your put.  If you don't ""succeed"" in acquiring shares on your first write (because the shares didn't get below the exercise price), you can continue to write puts and collect premium until you do get assigned. I have read the book ""Money for Nothing (And Your Stocks for FREE!)"" by Canadian author Derek Foster.  Despite the flashy title, the book essentially describes Derek's strategy for writing puts against dividend-paying value stocks he would love to own.  Derek picks quality companies that pay a dividend, and uses put writing to get in at lower-than-market prices.  Four Pillars reviewed the book and interviewed Derek Foster: Money for Nothing: Book Review and Interview with Derek Foster. Writing puts entails risk.  If the stock price drops to zero then you'll end up paying the put exercise price to acquire worthless shares!  So your down-side can easily be multiples of the premium collected.  Don't do this until and unless you understand exactly how this works.  It's advanced. Note also that your broker isn't likely to permit you to write puts without having sufficient cash or margin in your account to cover the case where you are forced to buy the stock.  You're better off having cash to secure your put buys, otherwise you may be forced into leverage (borrowing) when assigned.  Additional Resources: The Montreal Exchange options guide (PDF) that Cart already linked to is an excellent free resource for learning about options.  Refer to page 39, ""Writing secured put options"", for the strategy above. Other major options exchanges and organizations also provide high-quality free learning material:" Here is a quick and dirty explanation of options. In a nutshell, you pay a certain amount to buy a contract that gives you the right, but not the obligation, to buy or sell a stock at a predetermined price at some date in the future. They come in a few flavors:  I'll give you $100 if you let me buy 10,000 shares of XYZ for $10 more   per share than it is trading at today any time before   August 10th. I'll give you $100 if you promise to buy 10,000 shares of XYZ from me   for $10 less per share than it is trading at today if I ask before August 10th. There are also two main types based on the expiration behavior:  There are lots of strategies that employ options, too many to go into.  Two key uses are.. Leverage: Buying Call options can give you a much higher return on your investment than just investing in the actual stock. However, with much higher risk of losing all of your investment instead of just some of it when the stock drops. Hedging: If you already own the underlying stock, put options can be used to buy down risk of serious drops in a holding. "Some thoughts on your questions in order, Duration: You might want to look at the longest-dated option (often a ""LEAP""), for a couple reasons. One is that transaction costs (spread plus commission, especially spread) are killer on options, so a longer option means fewer transactions, since you don't have to keep rolling the option. Two is that any fundamentals-based views on stocks might tend to require 3-5 years to (relatively) reliably work out, so if you're a fundamental investor, a 3-6 month option isn't great. Over 3-6 months, momentum, short-term news, short squeezes, etc. can often dominate fundamentals in determining the price. One exception is if you just want to hedge a short-term event, such as a pending announcement on drug approval or something, and then you would buy the shortest option that still expires after the event; but options are usually super-expensive when they span an event like this. Strike: Strike price on a long option can be thought of as a tradeoff between the max loss and minimizing ""insurance costs."" That is, if you buy a deeply in-the-money put or call, the time value will be minimal and thus you aren't paying so much for ""insurance,"" but you may have 1/3 or 1/2 of the value of the underlying tied up in the option and subject to loss. If you buy a put or call ""at the money,"" then you might have only say 10% of the value of the underlying tied up in the option and subject to loss, but almost the whole 10% may be time value (insurance cost), so you are losing 10% if the underlying stock price stays flat. I think of the deep in-the-money options as similar to buying stocks on margin (but the ""implied"" interest costs may be less than consumer margin borrowing rates, and for long options you can't get a margin call). The at-the-money options are more like buying insurance, and it's expensive. The commissions and spreads add significant cost, on top of the natural time value cost of the option. The annual costs would generally exceed the long-run average return on a diversified stock fund, which is daunting. Undervalued/overvalued options, pt. 1: First thing is to be sure the options prices on a given underlying make sense at all; there are things that ""should"" hold, for example a synthetic long or short should match up to an actual long or short. These kinds of rules can break, for example on LinkedIn (LNKD) after its IPO, when shorting was not permitted, the synthetic long was quite a bit cheaper than a real long. Usually though this happens because the arbitrage is not practical. For example on LNKD, the shares to short weren't really available, so people doing synthetic shorts with options were driving up the price of the synthetic short and down the price of the synthetic long. If you did actually want to be long the stock, then the synthetic long was a great deal. However, a riskless arbitrage (buy synthetic long, short the stock) was not possible, and that's why the prices were messed up. Another basic relationship that should hold is put-call parity: http://en.wikipedia.org/wiki/Put%E2%80%93call_parity Undervalued/overvalued options, pt. 2: Assuming the relationship to the underlying is sane (synthetic positions equivalent to actual positions) then the valuation of the option could focus on volatility. That is, the time value of the option implies the stock will move a certain amount. If the time value is high and you think the stock won't move much, you might short the option, while if the time value is low and you think the stock will move a lot, you might buy the option. You can get implied volatility from your broker perhaps, or Morningstar.com for example has a bunch of data on option prices and the implied components of the price model. I don't know how useful this really is though. The spreads on options are so wide that making money on predicting volatility better than the market is pretty darn hard. That is, the spread probably exceeds the amount of the mispricing. The price of the underlying is more important to the value of an option than the assumed volatility. How many contracts: Each contract is 100 shares, so you just match that up. If you want to hedge 100 shares, buy one contract. To get the notional value of the underlying multiply by 100. So say you buy a call for $30, and the stock is trading at $100, then you have a call on 100 shares which are currently priced at $10,000 and the option will cost $30*100=3,000. You are leveraged about 3 to 1. (This points to an issue with options for individual investors, which is that one contract is a pretty large notional value relative to most portfolios.)" 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.