What effect does a company's earnings have on the price of its stock?
"No, the stock market is not there for speculation on corporate memorabilia.  At its base, it is there for investing in a business, the point of the investment being, of course, to make money.  A (successful) business earns money, and that makes it valuable to its owners since that money can be distributed to them.  Shares of stock are pieces of business ownership, and so are valuable.   If you knew that the business would have profit of $10,000,000 every year, and would distribute that to the owners of each of its 10,000,000 shares each year, you would know to that each share would receive $1 each year.  How much would such a share be worth to you?  If you could instead put money in a bank and get 5% a year back, to get $1 a year back you would have to put $20 into the bank.  So maybe that share of stock is worth about $20 to you.  If somebody offers to sell you such a share for $18, you might buy it; for $23, maybe you pass up the offer. But business is uncertain, and how much profit the business will make is uncertain and will vary through time.  So how much is a share of a real business worth?  This is a much harder call, and people use many different ways to come up with how much they should pay for a share.  Some people probably just think something like ""Apple is a good company making money, I'll buy a share at whatever price it is being offered at right now.""  Others look at every number available, build models of the company and the economy and the risks, all to estimate what a share might be worth, more or less.  There is no indisputable value for a share of a successful business. So, what effect does a company's earnings have on the price of its stock?  You can only say that for some of the people who might buy or sell shares, higher earnings will, all other thing being equal, have them be willing to spend more to buy it or demand more when selling it.  But how much more is not quantifiable but depends on each person's approach to the problem.  Higher earnings would tend to raise the price of the stock.  Yet there are other factors, such as people who had expected even higher earnings, whose actions would tend to lower the price, and people who are OK with the earnings now, but suspect trouble for the business is appearing on the horizon, whose actions would also tend to lower the price. This is why people say that a stock's price is determined by supply and demand." A common (and important) measure of a stock's value is the price/earnings ratio, so an increase in earnings will normally cause the stock price to increase. However, the price of the stock is based on a guess of the value of the company some time (6 months?) in the future. So an increase in earnings today probably makes a higher earnings more likely in the future, and puts upward pressure on the price of the stock. There are a lot of other factors in stock prices, such as publicity, dividends, revenue, trends, company stability, and company history. Earnings is a very important factor, but not the only factor determine the value (and so stock price) of a company. Your autograph analogy seems relevant to me. But it is not just speculation. In the long run, investing in stocks is like investing in the economy. In the long run, the economy is expected to grow , hence stock prices are expected to go up. Now in theory: the price of any financial instrument is equal to the net present value today of all the future cash flows from the instrument. So if company's earnings improve, shareholders hope that the earnings will trickle down to them either in form of dividends or in form of capital gain. So they buy the stock, creating demand for it. I can try to explain more if this did not make any sense. :) Market price of a stock typically trades in a range of Price/Earnings Ratio (P/E ratio). Or in other words, price of a stock = Earnings * P/E ratio Because of this direct proportionality of stock price with earnings, stock prices move in tandem with earnings.
I have heard that people say the greater earning means greater   intrinsic value of the company. Then, the stock price is largely based   on the intrinsic value. So increasing intrinsic value due to   increasing earning will lead to increasing stock price. Does this make   sense ? Yes though it may be worth dissecting portions here. As a company generates earnings, it has various choices for what it can do with that money. It can distribute some to shareholders in the form of dividends or re-invest to generate more earnings. What you're discussing in the first part is those earnings that could be used to increase the perceived value of the company. However, there can be more than a few interpretations of how to compute a company's intrinsic value and this is how one can have opinions ranging from companies being overvalued to undervalued overall. Of Mines, Forests, and Impatience would be an article giving examples that make things a bit more complex. Consider how would you evaluate a mine, a forest or a farm where each gives a different structure to the cash flow? This could be useful in running the numbers here. "It is important to first understand that true causation of share price may not relate to historical correlation. Just like with scientific experiments, correlation does not imply causation. But we use stock price correlation to attempt to infer causation, where it is reasonable to do so. And to do that you need to understand that prices change for many reasons; some company specific, some industry specific, some market specific. Companies in the same industry may correlate when that industry goes up or down; companies with the same market may correlate when that market goes up or down. In general, in most industries, it is reasonable to assume that competitor companies have stocks which strongly correlate (positively) with each-other to the extent that they do the same thing.  For a simple example, consider three resource companies: ""Oil Ltd."" [100% of its assets relate to Oil]; ""Oil and Iron Inc."" [50% of its value relates to Oil, 50% to Iron]; and ""Iron and Copper Ltd."" [50% of its value relates to Iron, 50% to Copper]. For each of these companies, there are many things which affect value, but one could naively simplify things by saying ""value of a resource company is defined by the expected future volume of goods mined/drilled * the expected resource price, less all fixed and variable costs"". So, one major thing that impacts resource companies is simply the current & projected price of those resources. This means that if the price of Oil goes up or down, it will partially affect the value of the two Oil companies above - but how much it affects each company will depend on the volume of Oil it drills, and the timeline that it expects to get that Oil. For example, maybe Oil and Iron Ltd. has no currently producing Oil rigs, but it has just made massive investments which expect to drill Oil in 2 years - and the market expects Oil prices to return to a high value in 2 years.  In that case, a drop in Oil would impact Oil Inc. severely, but perhaps it wouldn't impact Oil and Iron Ltd. as much. In this case, for the particular share price movement related to the price of Oil, the two companies would not be correlated. Iron and Copper Ltd. would be unaffected by the price of Oil [this is a simplification; Oil prices impact many areas of the economy], and therefore there would be no correlation at all between this company's shares. It is also likely that competitors face similar markets. If consumer spending goes down, then perhaps the stock of most consumer product companies would go down as well. There would be outliers, because specific companies may still succeed in a falling market, but in generally, there would be a lot of correlation between two companies with the same market.  In the case that you list, Sony vs Samsung, there would be some factors that correlate positively, and some that correlate negatively. A clean example would be Blackberry stock vs Apple stock - because Apple's success had specifically negative ramifications for Blackberry. And yet, other tech company competitors also succeeded in the same time period, meaning they did not correlate negatively with Apple." In order: A seller of the stock (duh!). You don't know who or why this stock was sold. It could be any reason, and is of no concern of yours. It doesn't matter. Investors (pension funds, hedge funds, individual investors, employees, management) sell stock for many reasons: need cash, litigation, differing objectives, sector rotation, etc. To you, this does not matter. Yes, it does affect stock market prices: If you were not willing to buy that amount of shares, and there were no other buyers at that price, the seller would likely choose to lower the price offered. By your purchase, you are supporting the price. If you believe in the efficient market hypothesis then the stock price reflects the information known to market participants. Consequently, if the 'market' expected earnings to rise, and they did, then the price won't change. Clearly there are circumstances, especially in the short term and for illiquid stocks, where this isn't true, but a lot of work points to this being the case on average. according to me it's the news about a particular stock which makes people to buy or sell it mostly thus creates a fluctuation in price . It also dependents on the major stock holder. Would you consider the owner of a company to be supporting the company? If you buy stock in the company you own a small part of that company. Your purchase also increases the share price, and thus the value of the company. Increased value allows the company to borrow more money to say expand operations. The affect that most individuals might have on share price is very very small. That doesn't mean it isn't the right thing for you to do if it is something you believe in. After all if enough people followed those same convictions it could have an impact on the company. "What does it mean in terms of share price? Should the share price increase by 15 cents?  No, but you're on the right track. In theory, the price of a share reflects it's ""share"" of time discounted future earnings. To put it concretely, imagine a company consistently earning 15 cents a share every year and paying it all out as dividends. If you only paid 25 cents for it, you could earn five cents a share by just holding it for two years. If you imagine that stocks are priced assuming a holding period of 20 years or so, so we'd expect the stock to cost less than 3 dollars.  More accurately, the share price reflects expected future earnings. If everyone is assuming this company is growing earnings every quarter, an announcement will only confirm information people have already been trading based on. So if this 15 cents announcement is a surprise, then we'd expect the stock price to rise as a function of both the ""surprise"" in earnings, and how long we expect them to stay at this new profitability level before competition claws their earnings away. Concretely, if 5 cents a share of that announcement were ""earnings surprise,"" you'd expect it to rise somewhere around a dollar." You are right that Facebook really doesn't get impacted as they got their $38. However it would make it slightly more difficult for Facebook to raise more money in future as large investors would be more cautious. This can keep the price lowers than it actually needs to be. Quite a few companies try to list the IPO at lower price so that it keeps going up and have more positive effect overall there by making it easier for future borrowings. See related question Why would a company care about the price of its own shares in the stock market? "When you buy a stock, you're really paying for a STREAM of earnings, from now till whenever. The job of an investor is to figure out how large that stream will be in the future. But if the stock price were the same as ""earnings"" (for one year), it would mean that you would get all future earnings for ""free."" That's not likely to happen unless 1) the company is in liquidation,"" meaning ""no future"" and 2) it earned ALL of the money it ever earned in the past year, meaning ""no past."" If there are likely to be any earnings in the future, you will have to pay for those future earnings, over and above what was earned in the most recent year." Here are some significant factors affect the company stock price performance: Usually, profitability is known to the public through the financial statements; it won't be 100% accurate and people would also trade the stock with the price not matching to the true value of the firm. Still there are dozens of other various reasons exist. People are just not behaving as rational as what the textbook describes when they are trading and investing. News about a company is not the only thing that affects its stock's price. There is also supply and demand.  That, of course, is influenced by news, but it is not the only actor.  An insider, with a large position in their company's stock, may want to diversify his overall portfolio and thus need to sell a large amount of stock.  That may be significant enough to increase supply and likely reduce the stock's price somewhat. That brings me to another influence on stock price: perception.  Executives, and other insiders with large positions in their company's stock, have to be careful about how and when they sell some of that stock as to not worry the markets.  Many investors watch insider selling to gauge the health of the company. Which brings me to another important point.  There are many things that may be considered news which is material to a certain company and its stock.  It is not just quarterly filings, earnings reports and such.  There is also news related to competitors, news about the economy or a certain sector, news about some weather event that affects a major supplier, news about a major earthquake that will impact the economy of a nation which can then have knock-on effects to other economies, etc... There are also a lot of investors with varying needs which will influence supply and demand.  An institutional investor, needing to diversify, may reduce their position in a stock and thus increase supply enough that it impacts the stock's price.  Meanwhile, individual investors will make their transactions at varying times during the day.  In the aggregate, that may have significant impacts on supply and demand. The overall point being that there are a lot of inputs and a lot of actors in a complicated system.  Even if you focus just on news, there are many things that fall into that category. News does not come out at regular intervals and it does not necessarily spread evenly.  That alone could make for a highly variable environment. Aside from the market implications Victor and JB King mention, another possible reason is the dividends they pay. Usually, the dividends a company pays are dependent on the profit the company made. if a company makes less profit, the dividends turn out smaller. This might incite unrest among the shareholders, because this means that they get paid less dividends, which makes that share more likely to be sold, and thus for the price to fall. 1) What's the point of paying a dividend if the stock price   automatically decreases? Don't the shareholders just break even? When the company earns cash beyond what is needed for expenses, the value of the firm increases. As a shareholder, you own a piece of that increased value as soon as the company earns it. When the dividend is paid, the value of the firm decreases, but you break even on the dividend transaction. The benefit to you in holding the company's shares is the continually increasing value, whether paid out to you, or retained. Be careful not to confuse the value of the firm with the stock price. The stock price is ever-changing, in the short-term driven mostly by investor emotion. Over the long term, by far the largest effect on stock price is earnings. Take an extreme, and simplistic example. The company never grows or shrinks, earnings are always the same, there is no inflation :) , and they pay everything out in dividends. By the reasoning above, the firm value never changes, so over the long-term the stock price will never change, but you still get your quarterly dividends. It is unlikely that buying 100 shares will have any effect on a stock's price, unless the stock's average trading volume is incredibly low.  That being said, no matter how many share you buy, there's no way to know what the impact on the price will be, because that's only one factor in how shares are priced.  If anyone could figure out the answer to your question then they'd be extremely rich, because they'd simply watch for big share trades and then buy those stocks on the way up. The market makers who actually execute the trades are the ones who set the prices, and most stocks have multiple market makers trading the stock, so the bid/ask you see is the highest bid and lowest ask.  The market makers set the price based on what the trend of the stock is.  If, for instance, there's a large number of sell orders against a stock, the market makers will start dropping the bid prices as they fill execution orders, and as they see buy orders increase, they'll raise ask prices as they fill execution orders.  The market makers earn the difference between what they paid to buy someone's stock who was selling and what they get from someone else who buys it. This is a simplified explanation, so pro traders, don't beat me up! (grin) So, basically, it takes quite a bit of share volume in one direction or another to affect a stock's price.  I can guarantee a 100-share trade wouldn't even be noticed by market makers. I hope this helps. Good luck! "I have some experience with this.  I have had fraudulent charges appear on my credit card statement and had to change my card number several times, despite (I believe) no carelessness on my part.  Every time that this has happened, I have never lost a penny due to fraud on my credit card.  The bank has ultimately removed the fraudulent charges in every instance. Given this, you'd think the consumer doesn't need to worry about this at all.  But it seems like credit card companies beg to differ. Yes, because although I have never lost a penny to fraud, the bank (or the merchant) loses money every time it happens.  The $0 liability protects you; the card security measures protect the bank. But... why should a consumer ever bother worrying about these in the first place, when he knows he legally can't be held responsible for fraudulent charges? What exactly is this new ""peace of mind"" that he supposedly gets by (say) using features like virtual account numbers that he doesn't already have? Although you shouldn't end up out any money when this happens, it is an inconvenience.  The bank will cancel your card and issue you a new number.  It may take a few days for you to receive your new card.  If you have another card to use, this isn't a big deal.  If you are out of state the day before you need to check out of a hotel and return a rental car with no backup credit card (as I have been), it is a big deal.  (In my case, I had to have the credit card company talk to the hotel to give them the new card number, and they were able to overnight me a new credit card so I could get home.  I now make sure I carry a backup credit card.) Should a consumer put any effort into worrying about this at all? (Why?) In my opinion, it makes sense to be careful what you do with your credit card number, if only to avoid the inconvenience.  Don't type your credit card number into an e-mail message, for example, and only use it on websites that you trust.  That having been said, it is not worth it to be paranoid about it, either.  No matter how careful you are, eventually you will probably use it at a store that gets hacked, or your card will get skimmed somewhere, and you'll need to get a new credit card number. The best way to protect yourself is to make sure that you go over your credit card statement each month and look for any fraudulent charges that the bank didn't catch."