How splits and dividends affect option prices
"Investopedia explains how a stock split impacts the stock's options: Each option contract is typically in control of 100 shares of an underlying security at a predetermined strike price. To find the new coverage of the option, take the split ratio and multiply by the old coverage (normally 100 shares). To find the new strike price, take the old strike price and divide by the split ratio. Say, for example, you own a call for 100 shares of XYZ with a strike price of $75. Now, if XYZ had a stock split of 2 for 1, then the option would now be for 200 shares with a strike price of $37.50. If, on the other hand, the stock split was 3 for 2, then the option would be for 150 shares with a strike price of $50. So, yes, a 2 for 1 stock split would halve the option strike prices.  Also, in case the Investopedia article isn't clear, after a split the options still control 100 shares per contract. Regarding how a dividend affects option prices, I found an article with a good explanation: As mentioned above, dividends payment could reduce the price of a stock due to reduction of the company's assets. It becomes intuitive to know that if a stock is expected to go down, its call options will drop in extrinsic value while its put options will gain in extrinsic value before it happens. Indeed, dividends deflate the extrinsic value of call options and inflate the extrinsic value of put options weeks or even months before an expected dividend payment.  Extrinsic value of Call Options are deflated due to dividends not only because of an expected reduction in the price of the stock but also due to the fact that call options buyers do not get paid the dividends that the stock buyers do. This makes call options of dividend paying stocks less attractive to own than the stocks itself, thereby depressing its extrinsic value. How much the value of call options drop due to dividends is really a function of its moneyness. In the money call options with high delta would be expected to drop the most on ex-date while out of the money call options with lower delta would be least affected. If a stock is expected to drop by a certain amount, that drop would already have been priced into the extrinsic value of its put options way beforehand. This is what happens to put options of dividend paying stocks. This effect is again a function of options moneyness but this time, in the money put options raise in extrinsic value more than out of the money put options. This is because in the money put options with delta of close to -1 would gain almost dollar or dollar on the drop of a stock. As such, in the money put options would rise in extrinsic value almost as much as the dividend rate itself while out of the money put options may not experience any changes since the dividend effect may not be strong enough to bring the stock down to take those out of the money put options in the money. So, no, a dividend of $1 will not necessarily decrease an option's price by $1 on the ex-dividend date.  It depends on whether it's a call or put option, and whether the option is ""in the money"" or ""out of the money"" and by how much."
Here is what I could find on the net: http://education.wallstreetsurvivor.com/options-symbol-changes-coming-february-12th-2010 So it sounds like it does not affect how you invest in options but only how you look them up.  I remember using a Bloomberg terminal and it wasn't clear what the expiry date of the option you were looking at was.  It looks like the new quote system addresses this. HTH. It will be similar to what you have said -- the options price will adjust accordingly following a stock split - Here's a good reference on different scenarios - Splits, Mergers, Spinoffs & Bankruptcies also if you have time to read Characteristics & Risks of Standardized Options "While derivative pricing models are better modeling reality as academia invests more into the subject, none sufficiently do. If, for example, one assumes that stock returns are lognormal for the purposes of pricing options like Black Scholes does, the only true dependent variable becomes log-standard deviation otherwise known as ""volatility"", producing the infamous ""volatility smile"" which disappears in the cases of models with more factors accounting for other mathematical moments such as mean, skew, and kurtosis, etc.  Still, these more advanced models are flawed, and suffer the same extreme time mispricing as Black Scholes.  In other words, one can model anything however one wants, but the worse the model, the stranger the results since volatility for a given expiration should be constant across all strikes and is with better models. In the case of pricing dividends, these can be adjusted for the many complexities of taxation, but the model becomes ever more complex and extremely computationally expensive for each eventuality.  Furthermore, with more complexity in any model, the likelihood of discovering a closed form in the short run is less. For equities in a low interest rate, not high dividend yield, not low volatility, low dividend tax environment, the standard swap pricing models will not provide results much different from one where a single low tax rate on dividends is assumed. If one is pricing a swap on equity outside of the bounds above, the dividend tax rate could have more of an effect, but for computational efficiency, applying a single assumed dividend tax rate would be optimal with D*(1-x), instead of D in a formula, where D is the dividend paid and x is the tax rate. In short, a closed form model is only as good as its assumptions, so if anomalies appear between the actual prices of swaps in the market and a swap model then that model is less correct than the one with smaller anomalies of the same type.  In other words, if pricing equity swaps without a dividend tax rate factored more closely matches the actual prices than pricing with dividend taxes factored then it could be assumed that pricing without a dividend tax factored is superior.  This all depends upon the data, and there doesn't seem to be much in academia to assist with a conclusion. If equity swaps do truly provide a tax advantage and both parties to a swap transaction are aware of this fact then it seems unlikely swap sellers wouldn't demand some of the tax advantage back in the form of a higher price.  A model is no defense since volatility curves persist despite what Black Scholes says they should be." For all stocks, expected Dividends are a part of the price it is traded for - consider that originally, the whole idea of stocks was to participate in the earnings of the company = get dividends. The day the dividend is paid, that expectation is of course removed, and thereby the stock value reduced by just the amount of dividend paid. You will see that behavior for all stocks, everywhere. The dividend in your example is just uncommonly high relative to the stock price; but that is a company decision - they can decide whatever amount they want as a dividend. In other words, the day before dividend payments, investors value the stock at ~14 $, plus an expected dividend payment of 12 $, which adds to 26 $. The day after the dividend payment, investors still value the stock at ~14 $, plus no more dividend payment = 0 $. Nothing changed really in the valuation. A one year period of study - Stock A trades at $100, and doesn't increase in value, but has $10 in dividends over the period.  Stock B starts at $100, no dividend, and ends at $105. However you account for this, it would be incorrect to ignore stock A's 10% return over the period.  To flip to a real example, MoneyChimp shows the S&P return from Jan 1980 to Dec 2012 as +3264% yet, the index only rose from 107.94 to 1426.19 or +1221%.  The error expands with greater time and larger dividends involved, a good analysis won't ignore any dividends or splits. "There is a white paper on ""The weekend effect of equity options"" it is a good paper and shows that (for the most part) option values do lose money from Friday to Monday. Which makes sense because it is getting closer to expiration. Of course this not something that can be counted on 100%.  If there is some bad news and the stock opens down on a Monday the puts would have increased and the calls decreased in value. Article Summary (from the authors): ""We find that returns on options on individual equities display markedly lower returns over weekends (Friday close to Monday close) relative to any other day of the week. These patterns are observed both in unhedged and delta-hedged positions, indicating that the effect is not the result of a weekend effect in the underlying securities. We find even stronger weekend effects in implied volatilities, but only after an adjustment to quote implied volatilities in terms of trading days rather than calendar days.""  ""Our results hold for puts and calls over a wide range of maturities and strike prices, for both equally weighted portfolios and for portfolios weighted by the market value of open interest, and also for samples that include only the most liquid options in the market. We find no evidence of a weekly seasonal in bid-ask spreads, trading volume, or open interest that could drive the effect. We also find little evidence that weekend returns are driven by higher levels of risk over the weekend.  ""The effect is particularly strong over expiration weekends, and it is also present to a lesser degree over mid-week holidays. Finally, the effect is stronger when the TED spread and market volatility are high, which we interpret as providing support for a limits to arbitrage explanation for the persistence of the effect."" - Christopher S. Jones & Joshua Shemes You can read more about this at this link for Memphis.edu" I have an example of a trade I made some time ago.  By entering the position as a covered call, I was out of pocket $5.10, and if the stock traded flat, i.e. closed at the same $7.10 16 months hence, I was up 39% or nearly 30%/yr. As compared to the stock holder, if the stock fell 28%, I'd still break even, vs his loss of 28%. Last, if the stock shot up, I'd get 7.50/5.10 or a 47% return, vs the shareholder who would need a price of $10.44 to reflect that return. Of course, a huge jump in the shares, say to $15, would benefit the option buyer, and I would have left money on the table. But this didn't happen. The stock was at $8 at expiration, and I got my 47% return. The option buyer got 50 cents for his $2 bet.  Note, the $2 option price reflected a very high implied volatility. I believe this depends on the broker's policies. For example, here is Vanguard's policy (from https://personal.vanguard.com/us/whatweoffer/stocksbondscds/brokeragedividendprogram): Does selling shares affect a distribution? If you sell the entire position two days or more before the dividend-payable date, your distribution will be paid in cash. If, however, you sell an entire position within the two day time frame of the security's payable date, the dividend will be reinvested, resulting in additional shares. Selling these subsequent shares will require another sell order, which will incur additional commission charges. Dividends which would have been reinvested into less than one whole share will be automatically liquidated into cash. If you want to guarantee you receive no fractional shares, I'd call your broker and ask whether selling stock ABC on a particular date will result in the dividend being paid in shares. No, the expense ratio would be something you wouldn't be charged. If you bought shares of the ETF long, then the dividends are usually reduced by the expense ratio if you wanted to know where to find that charge in general. You would have to make up for any dividends the underlying stocks as part of general shorting since the idea is that once you buy to put back the shares, it has to appear as if they weren't missing in the first place. No, the authorized participant would handle changes to the underlying structure if needed. Thanks. Just to clarify I am looking for a more value-neutral answer in terms of things like Sharpe ratios. I think it's an oversimplification to say that on average you lose money because of put options - even if they expire uselessly 90% of the time, they still have some expected payoff that kicks in 10% of the time, and if the price is less than the expected payoff you will earn money in the long term by investing in put options (I am sure you know this as a PhD student I just wanted to get it out there.)I guess more formally my question would be are there studies on whether options prices correspond well to the diversification benefits they offer from an MPT point of view. The price of a share of a mutual fund is its Net Asset Value (nav). Before the payout of dividends and capital gain distribution, the fund was holding both stock shares and cash that resulted from dividends and capital gains. After the payout, a share only holds the stock. Therefore once the cash is paid out the NAV must drop by the same amount as was paid out per share. Thus of course assumes no other activity or valuation changes of the underlying assets. Regular market activity will obscure what the payout does to the NAV. Scrip dividends are similar to stock splits. With a stock split, 100 shares can turn into 200 shares; with scrip dividends they might turn into 105 shares. Most corporations have a limit on the number of shares that they can issue, which is written into their corporate charter.  They usually sell a number that is fewer than the maximum authorized number so that they have a reserve for secondary offerings, employee incentives, etc. In a scrip dividend, the company is distributing authorized shares that were not previously issued.  This reduces the number of shares that it has to sell in the future to raise capital, so it reduces the assets of the company. In a split, every share (including the authorized shares that haven't been distributed) are divided.  This results in more total shares (which then trade at a price that's roughly proportional to the split), but it does not reduce the assets of the company. It depends how deep in the money it is, compared to the dividend.  Even an in the money call has some time premium. As the call holder, if I exercise instead of selling the call, I am trading the potential for a dividend, which I won't receive, for getting that time premium back by selling.  Given the above, you'll notice a slight distortion in options pricing as a dividend date approaches, as the option will reflect not just the time premium, but the fact that exercising with grab the dividend.  Edit to address your comment - $10 stock, $9 strike, 50 cent div. If the option price is high, say $2, because there's a year till expiration, exercising makes no sense. If it's just $1.10, I gain 40 cents by exercising and selling after the dividend. "If I held stock in these companies yesterday, would I have profited by these gains? No.  For DZSI, your 5 shares at $1.10 would now be 1 share at $5.50, so you would have the same total amount.  For SGY, they closed at $6.95, and opened at $32.80, so your five shares at $6.95 would now be one share at $32.80, so you would have actually lost money (not purely because of the split, but because the ""new"" shares are trading lower then the expected 1:5 split price).  A split in general does not affect market cap (how much your total shares are worth) but there may be residual effects that cause the market value to fluctuate after a split that affect the price."