Capital losses on early-purchased stock?
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.
This is not right. Inferring the employee stock pool’s takeaway is not as easy as just taking a fraction of the purchase price. As an example, that wouldn’t account for any preferred returns of other ownership classes, among other things.   All considered though, it’s reasonable to assume that the employee stock pool will get some premium. Best of luck. If the company reported a loss at the previous quarter when the stock what at say $20/share, and now just before the company's next quarterly report, the stock trades around $10/share. There is a misunderstanding here, the company doesn't sell stock, they sell products (or services). Stock/share traded at equity market. Here is the illustration/chronology to give you better insight:   Now addressing the question What if the stock's price change? Let say, Its drop from $10 to $1 Is it affect XYZ revenue ? No why? because XYZ selling ads not their stocks the formula for revenue revenue = products (in this case: ads) * quantity the equation doesn't involve capital (stock's purchasing) "You have a sequence of questions here, so a sequence of answers: If you stopped at the point where you had multiple wins with a net profit of $72, then you would pay regular income tax on that $72. It's a short term capital gain, which does not get special tax treatment, and the fact that you made it on multiple transactions does not matter. When you enter your next transaction that takes the hypothetical loss the question gets more complicated. In either case, you are paying a percentage on net gains.  If you took a two year view in the second case and you don't have anything to offset your loss in the second year, then I guess you could say that you paid more tax than you won in the total sequence of trades over the two years. Although you picked a sequence of trades where it does not appear to play, if you're going to pursue this type of strategy then you are likely at some point to run into a case where the ""wash sale"" rules apply, so you should be aware of that.  You can find information on this elsewhere on this site and also, for example, here: http://www.marketwatch.com/story/understanding-the-wash-sale-rules-2015-03-02  Basically these rules require you to defer recording a loss under some circumstances where you have rapid wins and losses on ""substantially identical"" securities. EDIT A slight correction, you can take part of your losses in the second year even if you have no off-setting gain.  From the IRS: If your capital losses exceed your capital gains, the amount of the excess loss that you can claim on line 13 of Form 1040 to lower your income is the lesser of $3,000, ($1,500 if you are married filing separately)" Is it just -34*4.58= -$155.72 for CCC and -11*0.41= -$4.51 for DDD? Yes it needs to be recorded as negative because at some point in time, the investor will have to spend money to buy these shares [cover the short sell and return the borrowed shares]. Whether the investor made profit or loss will not be reflected as you are only reflecting the current share inventory. As I recall, the gain for ISOs is considered ordinary income, and capital losses can only negate up to $3000 of this each year.  If you exercised and held the stock, you have ordinary income to the exercise price, and cap gain above that, if you hold the stock for two years.  EDIT - as noted below, this answer works for USians who found this question, but not for the OP who is Canadian, or at least asked a question at it relates to Canada's tax code. When you sell a stock that you own, you realize gains, or losses. Short-term gains, realized within a year of buying and selling an asset, are taxed at your maximum (or marginal) tax rate. Long term-gains, realized after a year, are taxed at a lower, preferential rate. The first thing to consider is losses. Losses can be cancelled against gains, reducing your tax liability. Losses can also be carried over to the next tax year and be redeemed against those gains. When you own a bunch of the same type of stock, bought at different times and prices, you can choose which shares to sell. This allows you to decide whether you realize short- or long-term gains (or losses). This is known as lot matching (or order matching). You want to sell the shares that lost value before selling the ones that gained value. Booking losses reduces your taxes; booking gains increases them. If faced with a choice between booking short term and long term losses, I'd go with the former. Since net short-term gains are taxed at a higher rate, I'd want to minimize the short-term tax liability before moving on to long-term tax liability. If my remaining shares had gains, I'd sell the ones purchased earliest since long-term gains are taxed at a lower rate, and delaying the booking of gains converts short-term gains into long-term ones. If there's a formula for this, I'd say it's  (profit - loss) x (tax bracket) = tax paid For reporting purposes, I would treat the purchase and sale of gold like a purchase and sale of a stock. The place to do so is Schedule D. (And if it's the wrong form, but you reported it, there is might not be a penalty, whereas there is a penalty for NOT reporting.) The long term gain would be at capital gains rates. The short term gain would be at ordinary income rates. And if you have two coins bought at two different times, you get to choose which one to report (as long as you report the OTHER one when you sell the second coin). If you do this, you own a stock worth $1, with a basis of $2. The loss doesn't get realized until the shares are sold. Of course, we hope you see the stock increase above that price, else, why do this? You bought the stock at some point in the past. You must have had a reason for this purchase. Has the recent change in price changed the reason you bought the stock? You must assume your losses are sunk costs. No matter what action you take, you can not recover your losses. Do not attempt to hold the stock in the hopes of regaining value, or sell it to stop losses. Instead approach this event as if this very day, you were given shares of the company's stock at their current market value for free as a gift. In this hypothetical situation, would you hold the shares, or sell them? Use that to judge your options. Not everyone, myself included, can handle the mental stress of watching share prices change. You can always consider trading index funds instead, which are much less volatile but will provide consistent, albeit, boring returns. This may or may not be you, but it's an option. Finally, do not keep money in the market you are not prepared to lose. It seems obvious, but if you lost 40% today, you could lose 100% tomorrow. My understanding is that losses are first deductible against any capital gains you may have, then against your regular income (up to $3,000 per year).  If you still have a loss after that, the loss may be carried over to offset capital gains or income in subsequent years As you suspect, a short term capital loss is deductible against short term capital gains and long term losses are deductible against long term gains.  So taking the loss now MIGHT be beneficial from a tax perspective.  I say MIGHT because there are a couple scenarios in which it either may not matter, or actually be detrimental: If you don't have any short term capital gains this year, but you have long term capital gains, you would have to use the short term loss to offset the long term gain before you could apply it to ordinary income.  So in that situation you lose out on the difference between the long term tax rate (15%) and your ordinary income rate (potentially higher). If you keep the stock, and sell it for a long term loss next year, but you only have short-term capital gains or no capital gains next year, then you may use the long term loss to offset your short-term gains (first) or your ordinary income.   Clear as mud? The whole mess is outlined in IRS Publication 550 Finally, if you still think the stock is good, but just want to take the tax loss, you can sell the stock now (to realize the loss) then re-buy it in 30 days.  This is called Tax Loss Harvesting.  The 30 day delay is an IRS requirement for being allowed to realize the loss. You are correct. She cannot claim the initial loss of $1,000 on her taxes, she can only report the $500 profit. However, the IRS does allow her to add the $1,000 loss to the basis cost of her replacement shares. e.g. Yes, an overall $500 loss on the stock can be claimed. Since the day trader sold both lots she acquired, the Wash Sale rule has no net impact on her taxes. The Wash Sale rule would come into play if within thirty days of second sale, she purchased the stock a third time. Then she would have to amend her taxes because claiming the $500 loss would no longer be a valid under the Wash Sale rule. It would have to be added to the cost basis of the most recent purchase. "Generally if you are using FIFO (first in, first out) accounting, you will need to match the transactions based on the number of shares. In your example, at the beginning of day 6, you had two lots of shares, 100 @ 50 and 10 @ 52.  On that day you sold 50 shares, and using FIFO, you sold 50 shares of the first lot.  This leaves you with 50 @ 50 and 10 @ 52, and a taxable capital gain on the 50 shares you sold. Note that commissions incurred buying the shares increase your basis, and commissions incurred selling the shares decrease your proceeds.  So if you spent $10 per trade, your basis on the 100 @ 50 lot was $5010, and the proceeds on your 50 @ 60 sale were $2990.  In this example you sold half of the lot, so your basis for the sale was half of $5010 or $2505, so your capital gain is $2990 - 2505 = $485. The sales you describe are also ""wash sales"", in that you sold stock and bought back an equivalent stock within 30 days.  Generally this is only relevant if one of the sales was at a loss but you will need to account for this in your code.  You can look up the definition of wash sale, it starts to get complex. If you are writing code to handle this in any generic situation you will also have to handle stock splits, spin-offs, mergers, etc. which change the number of shares you own and their cost basis.  I have implemented this myself and I have written about 25-30 custom routines, one for each kind of transaction that I've encountered.  The structure of these deals is limited only by the imagination of investment bankers so I think it is impossible to write a single generic algorithm that handles them all, instead I have a framework that I update each quarter as new transactions occur." Note that the rules around wash sales vary depending on where you live. For the U.S., the wash sale rules say that you cannot buy a substantially identical stock or security within 30 days (before or after) your sale. So, you could sell your stock today to lock in the capital losses. However, you would then have to wait at least 30 days before purchasing it back. If you bought it back within 30 days, you would disqualify the capital loss event. The risk, of course, is that the stock's price goes up substantially while you are waiting for the wash sale period. It's up to you to determine if the risk outweighs the benefit of locking in your capital losses. Note that this applies regardless of whether you sell SOME or ALL of the stock. Or indeed, if we are talking about securities other than stocks. "I've bought ISO stock over they years -- in NYSE traded companies.  Every time I've done so, they've done what's called ""sell-to-cover"".  And the gubmint treats the difference between FMV and purchase price as if it's part of your salary.  And for me, they've sold some stock extra to pay estimated taxes. So, if I got this right...  20,000 shares at $3 costs you 60,000 to buy them.  In my sell-to-cover at 5 scenario: did I get that right?  Keeping only 4,000 shares out of 20,000 doesn't feel right.  Maybe because I've always sold at a much ratio between strike price and FMV. Note I made some assumptions:  first is that the company will sell some of the stock to pay the taxes for you.  Second is your marginal tax rate.  Before you do anything check these. Is there some reason to exercise immediately?  I'd wait, personally."