Does negative P/E ratio mean stock is weak?
P/E is the number of years it would take for the company to earn its share price.  You take share price divided by annual earnings per share.  You can take the current reported quarterly earnings per share times 4, you can take the sum of the past four actual quarters earnings per share or you can take some projected earnings per share. It has little to do with a company's actual finances apart from the earnings per share.  It doesn't say much about the health of a company's balance sheet, and is definitely not an indicator for bankruptcy.  It's mostly a measure of the market's assumptions of the company's ability to grow earnings or maintain it's current earnings growth.   A share price of $40 trading for a P/E ratio of 10 means it will take the company 10 years to earn $40 per share, it means there's current annual earnings per share of $4.  A different company may also be earning $4 per share but trade at 100 times earnings for a share price of $400.  By this measure alone neither company is more or less healthy than the other.  One just commands more faith in the future growth from the market. To circle back to your question regarding a negative P/E, a negative P/E ratio means the company is reporting negative earnings (running at a loss).  Again, this may or may not indicate an imminent bankruptcy.  Increasing balance sheet debt with decreasing revenue and or earnings and or balance sheet assets will be a better way to assess bankruptcy risk.
"To perhaps better explain the ""why"" behind this rule of thumb, first think of what it means when the P/E ratio changes.  If the P/E ratio increases, then this means the stock has become more expensive (in relative terms)--for example, an increase in the price but no change in the earnings means you are now paying more for each cent of earnings than you previously were; or, a decrease in the earnings but no change in the price means you are now paying the same for less earnings. Keeping this in mind, consider what happens to the PE ratio when earnings increase (grow)-- if the price of the stock remains the same, then the stock has actually become relatively ""cheaper"", since you are now getting more earnings for the same price.  All else equal, we would not expect this to happen--instead, we would expect the price of the stock to increase as well proportionate to the earnings growth.  Therefore, a stock whose PE ratio is growing at a rate that is faster than its earnings are growing is becoming more expensive (the price paid per cent of earnings is increasing).  Similarly, a stock whose PE ratio is growing at a slower rate than its earnings is becoming cheaper (the price paid per cent of earnings is decreasing).  Finally, a stock whose P/E ratio is growing at the same rate as its earnings are growing is retaining the same relative valuation--even though the actual price of the stock may be increasing, you are paying the same amount for each cent of the underlying company's earnings." Buy low, sell high. I think a lot of people apply that advice wrongly. Instead of using this as advice about when to buy and when to sell, you should use it as advice about when not to buy and when not to sell. Don't buy when P/Es cannot support the current stock price. Don't sell when stocks have already fallen due to a market panic. Don't follow the herd or you will get trampled when they reverse direction in a panic.  If you are smart enough to sell ahead of the panics, more power to you, but you should be using more than a 52-week high on a graph to make that decision. And the kind folk at Yahoo Finance came to the same conclusion.  Keep in mind, book value for a company is like looking at my book value, all assets and liabilities, which is certainly important, but it ignores my earnings.  BAC (Bank of America) has a book value of $20, but trades at $8. Some High Tech companies have negative book values, but are turning an ongoing profit, and trade for real money. In the equity world, if a stock trades at 110 and is going to pay a dividend of 10 in a few days, an option expiring after the ex date would take the dividend into account and would trade as if the stock were trading at 100. (Negative) interest rates may also lead to a similar effect. In the commodity world the cost of carry needs to be taken into account. "In general, there should be a ""liquidity premium"" which means that less-liquid stocks should be cheaper. That's because to buy such a stock, you should demand a higher rate of return to compensate for the liquidity risk (the possibility that you won't be able to sell easily). Lower initial price = higher eventual rate of return. That's what's meant when Investopedia says the security would be cheaper (on average). Is liquidity good? It depends. Here's what illiquidity is. Imagine you own a rare piece of art. Say there are 10 people in the world who collect this type of art, and would appreciate what you own. That's an illiquid asset, because when you want to sell, maybe those 10 people aren't buying - maybe they don't want your particular piece, or they all happen to be short on funds. Or maybe worse, only one of them is buying, so they have all the negotiating leverage. You'll have to lower your price if you're really in a hurry to sell. Maybe if you lower your price enough, you can get one of the 10 buyers interested, even if none were initially. An illiquid asset is bad for sellers. Illiquid means there aren't enough buyers for you to get a bidding war going at the time of your choosing. You'll potentially have to wait around for buyers to turn up, or for a stock, maybe you'd have to sell a little bit at a time as buyers want the shares. Illiquid can be bad for buyers, too, if the buyer is for some reason in a hurry; maybe nobody is selling at any given time. But, usually buyers don't have to be in a hurry. An exception may be if you short sell something illiquid (brokers often won't let you do this, btw). In that case you could be a forced buyer and this could be very bad on an illiquid security. If there are only one or two sellers out there, they now have the negotiating leverage and they can ask whatever price they want. Illiquidity is very bad when mixed with margin or short sales because of the potential for forced trades at inopportune times. There are plenty of obscure penny stocks where there might be only one or two trades per day, or fewer. The spread is going to be high on these because the bids at a given time will just be lowball offers from buyers who aren't really all that interested, unless you want to give your stock away, in which case they'll take it. And the asks are going to be from sellers who want to get a decent price, but maybe there aren't really any buyers willing to pay, so the ask is just sitting there with no takers. The bids and asks may be limit orders that have been sitting open for 3 weeks and forgotten about. Contrast with a liquid asset. For example, a popular-model used car in good condition would be a lot more liquid than a rare piece of art, though not nearly as liquid as most stocks. You can probably find several people that want to buy it living nearby, and you're not going to have to drop the price to get a buyer to show up. You might even get those buyers in a bidding war. From illiquid penny stocks, there's a continuum all the way up to the most heavily-traded stocks such as those in the S&P500. With these at a given moment there will be thousands of buyers and sellers, so the spread is going to close down to nearly zero. If you think about it, just statistically, if there are thousands of bids and thousands of asks, then the closest bid-ask pair is going to be close together. That's a narrow spread. While if there are 3 bids and 2 asks on some illiquid penny stock, they might be dollars away from each other, and the number of shares desired might not match up. You can see how liquidity is good in some situations and not in others. An illiquid asset gives you more opportunity to get a good deal because there aren't a lot of other buyers and sellers around and there's some opportunity to ""negotiate"" within the wide spread. For some assets maybe you can literally negotiate by talking to the other party, though obviously not when trading stocks on an exchange. But an illiquid asset also means you might get a bad deal, especially if you need to sell quickly and the only buyers around are making lowball offers. So the time to buy illiquid assets is when you can take your time on both buying and selling, and will have no reason for a forced trade on a particular timeline. This usually means no debt is involved, since creditors (including your margin broker) can force you to trade. It also means you don't need to spend the money anytime soon, since if you suddenly needed the money you'd have a forced trade on your hands. If you have the time, then you put a price out there that's very good for you, and you wait for someone to show up and give you that price - this is how you get a good deal. One more note, another use of the term liquid is to refer to assets with low or zero volatility, such as money market funds. An asset with a lot of volatility around its intrinsic or true value is effectively illiquid even if there's high trade volume, in that any given point in time might not be a good time to sell, because the price isn't at the right level. Anyway, the general definition of a liquid investment is one that you'd be comfortable cashing out of at a moment's notice. In this sense, most stocks are not all that liquid, despite high trading volume. In different contexts people may use ""liquid"" in this sense or to mean a low bid-ask spread." If that condition is permanent -- the stock will NEVER pay dividends and you will NEVER be able to sell it -- then yes, it sounds to me like this is a worthless piece of paper. If there is some possibility that the stock will pay dividends in the future, or that a market will exist to sell it, then you are making a long-term investment. It all depends on how likely it is that the situation will change. If the investment is small, maybe it's worth it. Beta is an indication of a Stock's risk with respect to the market.  For instance if a stock had a beta of 1 it means it is in tandem with the S&P 500. If it is more than 1, the stock is volatile.  If it is less than 1, it implies market movement doesn't affect this stock much. Tech stocks and small cap stocks have high beta, utilities have low beta. (In general, not always). Hope this helps - I've tried to explain it in very simple terms! The idea here is to get an idea of how to value each business and thus normalize how highly prized is each dollar that a company makes.  While some companies may make millions and others make billions, how does one put these in proper context?  One way is to consider a dollar in earnings for the company.  How does a dollar in earnings for Google compare to a dollar for Coca-cola for example?  Some companies may be valued much higher than others and this is a way to see that as share price alone can be rather misleading since some companies can have millions of shares outstanding and split the shares to keep the share price in a certain range. Thus the idea isn't that an investor is paying for a dollar of earnings but rather how is that perceived as some companies may not have earnings and yet still be traded as start-ups and other companies may be running at a loss and thus the P/E isn't even meaningful in this case. Assuming everything but the P/E is the same, the lower P/E would represent a greater value in a sense, yes.  However, earnings growth rate can account for higher P/Es for some companies as if a company is expected to grow at 40% for a few years it may have a higher P/E than a company growing earnings at 5% for example. A lower Price/Book Value means company is undervalued. It could also mean something horribly wrong. While it may look like a good deal, remember; The P/E ratio is a measure of historic (the previous financial year) earnings against the current share price. If the P/E is high, this means that the market perceives a big increase in future earnings per share.  In other words, the perception is that this is a fast growing company.  Higher earnings may also equate to big increases in dividends and rapid expansion.  On the other hand, if the P/E is low, then there is a perception that either earnings per share are decreasing or that future growth in earnings is negligible.  In other words, low P/E equates to a perception of low future growth and therefore low prospects for future payout increases - possibly even decreases. The market is (rightly) usually willing to pay a premium for fast growing companies. Let's use an example: You buy 10 machines for 100k, and those machines produce products sold for a total of 10k/year in profit (ignoring labor/electricity/sales costs etc). If the typical investor requires a rate of return of 10% on this business, your company would be worth 100k.  In investing terms, you would have a PE ratio of 10.  The immediately-required return will be lower if substantially greater returns are expected in the future (expected growth), and the immediately required return will be higher if your business is expected to shrink. If at the end of the year you take your 10k and purchase another machine, your valuation will rise to 110k, because you can now produce 11k in earnings per year.  If your business has issued 10,000 shares, your share price will rise from $10 to $11.  Note that you did not just put cash in the bank, and that you now have a higher share price. At the end of year 2, with 11 machines, lets imagine that customer demand has fallen and you are forced to cut prices.  You somehow produce only 10k in profit, instead of the anticipated 11k.  Investors believe this 10k in annual profit will continue into the forseable future.  The investor who requires 10% return would then only value your company at 100k, and your share price would fall back from $11 to $10.  If your earnings had fallen even further to 9k, they might value you at 90k (9k/0.1=$90k).  You still have the same machines, but the market has changed in a way that make those machines less valuable. If you've gone from earning 10k in year one with 10 machines to 9k in year two with 11 machines, an investor might assume you'll make even less in year three, potentially only 8k, so the value of your company might even fall to 80k or lower.  Once it is assumed that your earnings will continue to shrink, an investor might value your business based on a higher required rate of return (e.g. maybe 20% instead of 10%), which would cause your share price to fall even further. There are books on the subject of valuing stocks. P/E ratio has nothing directly to do with the value of a company. It may be an indication that the stock is undervalued or overvalued, but does not indicate the value itself. The direct value of company is what it would fetch if it was liquidated. For example, if you bought a dry cleaner and sold all of the equipment and receivables, how much would you get? To value a living company, you can treat it like a bond. For example, assume the company generates $1 million in profit every year and has a liquidation value of $2 million. Given the risk profile of the business, let's say we would like to make 8% on average per year, then the value of the business is approximately $1/0.08 + $2 = $14.5 million to us. To someone who expects to make more or less the value might be different. If the company has growth potential, you can adjust this figure by estimating the estimated income at different percentage chances of growth and decline, a growth curve so to speak. The value is then the net area under this curve.  Of course, if you do this for NYSE and most NASDAQ stocks you will find that they have a capitalization way over these amounts. That is because they are being used as a store of wealth. People are buying the stocks just as a way to store money, not necessarily make a profit. It's kind of like buying land. Even though the land may never give you a penny of profit, you know you can always sell it and get your money back. Because of this, it is difficult to value high-profile equities. You are dealing with human psychology, not pennies and dollars. people implicity agree to sell stocks when a company does bad But, remember, when you sell the stock of a company that, in your estimation, 'did bad', someone else had to buy; otherwise, there is no sale. The someone else who bought your shares evidently disagrees with your assessment. Did you sell because the company didn't earn a profit at all? Did it not earn a profit because it's in a dead-end business that is slowly but inevitably declining to zero? Something like Sears Holdings? Or did it not make a profit because it is in an emerging market that will possibly someday become hugely profitable? Something like Tesla, Inc.? Did you sell because the company made a profit, but it was lower than expected? Did they make a lower-than-expected profit because of lower sales? Why were the sales lower? Is the industry declining? Was the snow too heavy to send the construction crews out? Did the company make a big investment to build a new plant that will, in a few years, yield even higher sales and profits? What are the profits year-over-year? Increasing? Declining? Usually, investors are willing to pay a premium, that is more than expected, for a stock in a company with robust growth.  As you can see, the mere fact that a company reported a profit is only one of many factors that determine the price of the shares in the market. Right, I understand minority interest but it is typically reported as a positive under liabilities instead of a negative. For example, when you are calculating the enterprise value of a company, you add back in the minority interest.    Enterprise Value= Market Share +Pref Equity + Min Interest+ Total Debt - Cash and ST Equivalents.    EV is used to quantify the total price of a company's worth. If you have negative Min Interest on your books, that will make your EV less than it should be, creating an incorrect valuation.   This just doesn't make any sense to me. Does it mean that the subsidiary that they had a stake in had a negative earning? Essentially, yes, Peter Lynch is talking about the PEG Ratio. The Price/Earnings to Growth (PEG) Ratio is where you take the p/e ratio and then divide that by the growth rate (which should include any dividends).  A lower number indicates that the stock is undervalued, and could be a good buy. Lynch's metric is the inverse of that: Growth rate divided by the p/e ratio.  It is the same idea, but in this case, a higher number indicates a good value for buying. In either case, the idea behind this ratio is that a fairly priced stock will have the p/e ratio equal the growth rate.  When your growth rate is larger than your p/e ratio, you are theoretically looking at an undervalued stock.