Two 1099B for same stock
It looks like what you're calling a name change was registered as a merger that resulted in an exchange of stock.  If that's the case, then what you've been told is correct.  You've got one long-term sale and one short-term sale. Based a quick read of the Form 8937 that was filed, it looks like there were multiple entities involved in this event, more than one of which existed prior to it. https://www.mylan.com/-/media/mylancom/files/form%208937%20for%20mylan%20n%20v.pdf
Say a stock is listed in Nasdaq, and the same company has a stock listed in Tsx. Does the Nasdaq price affect the Tsx price as trading commences? Not directly. Basically, an exchange is a market, and the price is defined only by supply and demand in that market. However, any substantial price differential for a commodity traded in multiple market creates an arbitrage opportunity, and there are many traders whose job it is exactly to find and use such opportunities. Their activity in turn has the effect of reducing the price differentials to the point where transaction costs make them unprofitable. With high-frequency traders around, the time for a price differential to disappear is nowadays measured in milliseconds. If a trader buys from one exchange, will it affect the price of the other? Only through the mechanism mentioned above.  Are there any benefits to being listed in two exchanges? It increases the liquidity of a stock. In my mind its not the same.   If growth is stock value then this is incorrect because of compound interest in stock price. $100 stock price after one year would be $105 and a dividend would be $2 Next year the stock would be  $110.20 (Compound Interest) and would the Dividend really go up in lock step with the stock price? Well probably not, but if it did then maybe you could call it the same. Even if the dollars are the same the growth rate is more variable than the dividends so its valuable to segregate the two. I am open to criticism, my answer is based on my personal experience and would love to hear contrary positions on this. "Your employer sends the money that you choose to contribute, plus employer match if any, to the administrator of the 401k plan who invests the money as you have directed, choosing between the alternatives offered by the administrator. Typically, the alternatives are several different mutual funds with different investment styles, e.g. a S&P 500 index fund, a bond fund, a money-market fund, etc.  Now, a statement such as ""I see my 401k is up 10%"" is meaningless unless you  tell us how you are making the comparison. For example, if you have just started employment and $200 goes into your 401k each month and is invested in a money-market fund (these are paying close to 0% interest  these days), then your 11th contribution increases your  401k from $2000 to $2200 and your 401k is ""up 10%"". More generally, suppose for simplicity that all the  401k investment is in just one (stock) mutual fund and that you own 100 shares of the fund as of right now.  Suppose also that your next contribution will not occur for three weeks when you get your next paycheck, at which time additional shares of the mutual fund will be purchased Now, the value of the mutual fund shares (often referred to as net asset value or NAV) fluctuates as stock prices rise and fall, and so the  401k balance = number of shares times NAV changes in accordance with these fluctuations. So,  if the NAV increases by 10% in the next two weeks, your 401k balance will have increased by 10%.  But you still own only 100 shares of the mutual fund. You cannot use the 10% increase  in value to buy more shares in the mutual fund  because there is no money to pay for the additional shares  you wish to purchase.  Notice that there is no point selling some of the shares (at the 10% higher NAV) to get cash  because you will be purchasing shares at the higher NAV too. You could, of course, sell shares of the stock mutual fund at the higher NAV and buy shares of some other fund available to you in the 401k plan.  One advantage of doing this inside the 401k plan is that you don't have to pay taxes (now) on the 10% gain that you have made on the sale. Outside tax-deferred plans such as 401k and IRA plans, such gains would be taxable in the year of the sale.  But note that selling the shares of the stock fund and buying something else indicates that you believe that the NAV of your stock mutual fund is unlikely to increase any further in the near future. A third possibility for your 401k being up by 10% is that the mutual fund paid a dividend or made a capital gains distribution in the two week period that we are discussing.  The NAV falls when such events occur, but if you have chosen to reinvest the dividends and capital gains, then the number of shares that you own goes up.  With the same example as before, the NAV goes up 10% in two weeks at which time a capital gains distribution occurs, and so the NAV falls back to where it was before.  So, before the capital gains distribution, you owned 100 shares at $10 NAV which went up to $11 NAV (10% increase in NAV) for a net increase in 401k balance from $1000 to $1100. The mutual fund distributes capital gains in the amount of $1 per share sending the NAV back to $10, but you take the $100 distribution and plow it back into the mutual fund, purchasing 10 shares at the new $10 NAV.  So now you own 110 shares at $10 NAV (no net change in price in two weeks) but your 401k balance is $1100, same as it was before the capital gains distribution and you are up 10%.  Or, you could have chosen to invest the distributions into, say, a bond fund available in your 401k plan and still be up 10%, with no change in your stock fund holding, but a new investment of $100 in a  bond fund. So, being up 10% can mean different things and does not necessarily mean that the ""return"" can be used to buy more shares." I don't know why stocks in some industries tend to have lower prices per share than others. It doesn't really matter much. Whether a company has 1,000,0000 shares selling for $100 each, or 10,000,000 shares selling for $10 each, either way the total value is the same. Companies generally like to keep the share price relatively low so that if someone wants to buy a small amount, they can. Like if the price was $10,000 per share, than an investor with less than $10,000 to put in that one stock would be priced out of the market. If it's $10, then if someone wants $10 they can buy one share, and if someone wants $10,000 they can buy 1000 shares. As to why energy stocks are volatile, I can think of several reasons. One, in our current world, energy is highly susceptible to politics. A lot of the world's energy comes from the Middle East, which is a notoriously unstable region. Any time there's conflict there, energy supplies from the region become uncertain. Oil-producing countries may embargo countries that they don't like. A war will, at the very least, interfere with transportation and shipping, and may result in oil wells being destroyed. Etc. Two, energy is consumed when you use it, and most consumers have very limited ability to stockpile. So you're constantly buying the energy you need as you need it. So if demand goes down, it is reflected immediately. Compare this to, say, clothing. Most people expect to keep the same clothes for years, wearing them repeatedly. (Hopefully washing them now and then!) So if for some reason you decided today that you only need three red shirts instead of four, this might not have any immediate impact on your buying. It could be months before you would have bought a new red shirt anyway. There is a tendency for the market to react rather slowly to changes in demand for shirts. But with energy, if you decide you only need to burn 3 gallons of gas per week instead of 4, your consumption goes down immediately, within days. Three, really adding to number two, energy is highly perishable, especially some forms of energy. If a solar power station is capable of producing 10 megawatts but today there is only demand for 9 megawatts, you can't save the unused megawatt for some future time when demand is higher. It's gone. (You can charge a battery with it, but that's pretty limited.) You can pile up coal or store natural gas in a tank until you need it, but you can't save the output of a power plant. Note numbers two and three also apply to food, which is why food production is also very volatile. Shares are partial ownership of the company. A company can issue (not create) more of the shares it owns at any time, to anyone, at any price -- subject to antitrust and similar regulations. If they wanted to, for example, flat-out give 10% of their retained interest to charity, they could do so. It shouldn't substantially affect the stock's trading for others unless there's a completely irrational demand for shares. Your question is missing information. The most probable reason is that the company made a split or a dividend paid in stock and that you might be confusing your historical price (which is relevant for tax purposes) with your actual market price. It is VERY important to understand this concepts before trading stocks. Initially, Each company has 10k shares. Company B has $500k money and possibly other assets. Every company has stated purpose. It can't randomly buy shares in some other firm.   Company A issued 5k new shares, which gives it $500k money. Listed companies can't make private placements without regulatory approvals. They have to put this in open market via Public issue or rights issue. Company B does the same thing, issuing 5k shares for $500k money. Company A bought those 5k shares using the $500k it just got There is no logical reason for shareholder of Company B to raise 5K from Company A for the said consideration. This would have to increase. "listed simultaneously in New York, London, and maybe even some Asian markets - is this correct? If the exchanges are not connected, then in primary market the shares are listed. On other exchanges, the ""Depository Receipts"" are listed. i.e. the Company will keep say 100,000 shares with the primary stock exchange / depository. Based on this it would create new instruments ""Depository Receipts"". They can be 1:1 or whatever ratio. hypothetically, if I want to buy all of the company's stock Even if it is on one exchange, buying all stocks would trigger various regulatory aspects of Companies Act, or Stock Exchange rules. This is not simple or easy like clicking some buttons and buying everything. That is, let's say that in New York the company has listed 1000 shares, and in London only 10 shares, each worth 10 USD Market capitalization is sum of all outstanding shares into value."