With respect to insider trading, what is considered “material information”?
"Some history: In the US, this is very tightly controlled and regulated. Although stock market securities insider trading is a relatively new crime around the world (20-30 year old), the United States  is exceptional for offering the longest sentences for it, although it is still far more lucrative than and carries lower sentences than something like petty larceny. The perception of illegal insider trading has changed in the US over the years, although it is based on much older fraud statutes the regulators and the courts have only really developed modern case law against insider trading in the past 20-30 years. The US relies on its vast network of registered broker-dealers to detect and report abnormal trading activity and the regulator (SEC) can quickly obtain emergency court orders from rent-a-judges (Administrative Law Judges) to freeze trader's assets to prevent them from withdrawing, or quickly enacting sanctions. So this reality helps deter trading on material inside information. So for someone that needs to get an information advantage on the market, it is [simply] necessary for them to rationalize how this information could be inferred from public sources.  Similarly there is a thin line between non-public information and public information, the ""lab experiment"" example would be material insider information, but the fact that there will be litigation over a company's key patents may be ""public"" as soon as the lawyer submits the complaint to the court system. It is also worth noting that there are A LOT of financial products trading in the capital markets, and illegal insider trading laws only applies to trading of shares of a company. So if a major holder in gold is about to liquidate all their holdings, being short gold futures is not subject to civil and criminal sanctions. Hope this helps. The above examples should help you understand what kind of information is material inside information and what kind is not, and how it is relevant to trading decisions." Material Information means that any information that can reasonable affect the share price of the company [upward or downward] as looked by the investors. The idea is to provide a level playing field to all investors. Hence it forces people having material information not to trade when they have this information that is not yet disclosed. Yes it happens all the time and laws are quite stringent. There is monitoring of share activity by regulators ... hence most of the times the companies come out with their own guidelines and top & senior management is prohibited from trading in their own company’s shares for pretty much round the year except few windows the company decides is safe. Now it may not be possible to monitor every small material info, but any large spike of stocks after certain announcements is investigated by regulators to verify any undue gains. For ex a person who never trades suddenly buys large qty of shares and it goes up and he sells again ... etc
"In *[United States vs. O'Hagan](https://en.wikipedia.org/wiki/United_States_v._O%27Hagan)* the Supreme Court established the precedent of interpreting SEC rule 10(b) using the ""misappropriation theory"". The theory establishes that:  &gt; misappropriating confidential information for securities trading purposes, in breach of a duty owed to the source of that information, gives rise to a duty to disclose or abstain.   You're correct that from a legal perspective the rules are anything but clear outside of company insiders. However, your own admission is consistent with what anyone in the securities industry knows is true - if you trade on material non-public information, you risk being charged.  I think most would conclude that it's unethical irrespective of the letter of the law. It damages the integrity and functioning of markets. Furthermore, if the law was clarified, I think it's highly unlikely it would state ""trading on material non-public information is permissible for anyone who is not a company insider"". Instead, I would expect it to be consistent with ""Trading on material non-public information is illegal. If in doubt, abstain."" And this is exactly what the government officials should be doing - abstaining." well you had it a bit backwards. the more liquid a market is, the less important the idea of insider information becomes. this is the opposite in less liquid markets - such as low volatile stocks about to announce earnings. knowing the earnings would net you a much larger percentage than, say, knowing if the ECB will cut rates of not. the change will be a much larger % and as with currencies, it is more important to know what the major players are planning - as in, central banks and reserves, carry trades, etc. I think you're looking for the public float: Public float or the unqualified term may also refer to the number of   outstanding shares in the hands of public investors as opposed to   company officers, directors, or controlling-interest investors.   Assuming the insider held shares are not traded, these shares are the   publicly traded ones. The float is calculated by subtracting   restricted shares from outstanding shares. As mentioned, Treasury stock is probably the most narrow definition of restricted stock (not publicly traded), but shares held by corporate officers or majority investors are often included in the definition as well. In any case, the balance sheet is indeed a good place to start. Insider trading is any trading done on material non-public information relating to an instrument.  If my sister, who works for a drugs testing company, tells me that stage 3 trials of a drug look like they will fail and I trade on that information (probably by shorting a company's stock) that is insider trading. If an employee of that firm trades on that same stock knowing that the trials are likely to fail that is too. If an employee of that company trades on the stock without knowing that information that is NOT insider trading. If I know from an insider I met at the pub that a large orange producer has seen a fall in production due to a blight and I trade on oranges futures, even though I am not directly trading in the stock it is still insider trading. I mentioned that the information must be material, that means that it must have the potential to move the market; if I know that a firm is going to increase profits by 10% this year it is not material if analyst expectations are for a similar rise. You are right that small scale insider trading, such as by employees and their families, is relatively unregulated and unchecked but directors and C-level employees of a firm are required to publish all and any dealings that they have in the stock and several have been caught and penalized for insider trading. edit: http://www.sec.gov/spotlight/insidertrading/cases.shtml details some cases, many involving director and C-level employees, that the SEC has prosecuted recently. Incidentally I work in financial fraud monitoring and we use an analytic based on previous days' trades and today's news (i.e. when the information becomes public) to identify traders who might either be indulging in or receiving orders to trade on insider information. Essentially this works by looking for large changes in position against an instrument that later has material information releases relevant to it. One final thing to think about: given that being caught will generally cause perpetrators to go to prison and be banned from director level jobs and/or trading for life as well as a large, life-changing fine and a massive loss of reputation not many people with insider information want to risk trading on it, myself included. Arguably the money made or lost on the particular stock in question wouldn't have happened without the story. The AIs are just taking advantage of market conditions caused by the story. The person who planted the story bought the stock prior to the story being dropped and sold before the stock dropped back down, which is illegal. "How on earth can you possibly know what is going on in individual company X?  The sole exception is if it is your own company. The stock markets of the world are in fact a nest of sharks.  The big sharks essentially make money out of the little sharks.  Some little sharks manage not to be eaten, and grow bigger.  Good luck with that. ""Insider trading"" is, when found out, a crime these days.  But ""insider knowledge"", ""insider hints"", ""knowledge of market sentiment"" and indeed just rumours about a given company are the kinds of things you won't particularly get to hear of in the fog of disinformation, and don't particularly want to waste your time with for a very uncertain loss or gain at the end of the year. The thing I find annoying about mutual funds is that they can be very stupid, and I speculate that it may be the consequence of the marketing on the one hand, and the commission structure on the other.  I started cashing in my funds in late 2007, following the collapse of Northern Rock here in the UK.  The ""2008"" crisis was in fact the slowest economic car crash in history. But very very few mutual funds saw, or seemed to see, the way the wind was blowing, and switch massively to cash. If the punters had the courage to hang on, of course, mostly stocks bounced back in 2009 and 2010.  Moral: remember you can cash your stuff in any time you want." A lot will depend on wether you have in your possession the physical share documents or just numbers in your brokerage portfolio. Electronic shares are not traceable as they do not exist as individual entities. ETrade certainly knows who bought how much, but no concept of which ones. Lets say ET buys 1000 shares of Acme, their database looks like this: Now they sell 400 shares to Bob: Bob sells 200, Alice buys 100: ( skipped one transaction for brevity ) Did Alice get 100 shares out of ET's original 1000, or did she get 100 shares that were previously owned by Bob? Or 27 from ET and 73 from ET? Another, less exact way to picture the process is one share is 1ml of liquid. If you return 50ml to the pot it becomes indistinguishable from the rest. Retail companies selling their real estate holdings isn't uncommon and is actually pushed for by shareholders sometimes (see Macy's and Starboard Value). The fact that the CEO bought them seems unique but not necessarily means there was an issue. I would think that type of transaction would get a lot of scrutiny so would be surprised if he could pull off any fuckery. The disclosure seems like it might be a pretty standard disclosure known as a related party transaction that again isn't in and of itself an issue Compensation information is available in the annual reports (10-k filings) which are available from the SEC EDGAR system or, generally, the company's website.  Additionally, insider transactions are reported to the SEC so you can see when an insider buys or sells stock or exercises options received as compensation. Background: Nowadays board and officers seem to secretly steal money from shareholders through options and other ways. The stock buybacks that people think should boost the earnings per stock is in reality issued back to the management of the company and is a more stealth way to take money from the company compared to take higher salaries. ... How do you know this is happening if you don't know where to go to get the data needed to determine whether or not this is happening?  Do you really think company share buybacks involve just the amount of shares to pay an executive?  Apple has bought back $117,000,000,000 worth of shares from the fourth quarter 2012 through the second quarter 2016, and paid a pretty substantial amount in dividends over the same period.  Do you really think these shares were simply handed to the executives?  The huge pension funds and other huge investors would not let this slide for very long if it were even close to being true. Don't come to an unfounded conclusion then seek data to prove your position.  Look at and analyze data THEN come to a conclusion. "The reason that stock buybacks are not considered insider trading is because the offers are open to all on equal terms to everyone outside the company. Even if the company knows ""inside"" information, it's not supposed to tell it (and company executives are not allowed to tender shares, unless they had previously set up a ""blind"" selling program on a""schedule."") If that's actually the case, no one investor is better informed than another, and hence there is no insider trading. The issue of inside trading is that ""insiders"" ARE better informed." More shares mean less volatility because it takes a larger number of trades, a larger number of shares per trade, or a combination of both to raise or lower the stock price. Institutional investors (mutual funds, pensions, hedge funds, other investment firms, etc) are the sorts of organizations with the large amounts of money needed to move a stock price one way or the other.  But the more floating shares there are in a company, the harder it is for one or two firms to move a stock price.  A company with fewer floating shares wouldn't require as many trades (or as many shares per trade) to see wider swings in price. When it comes to stock price, insider trading isn't the same as manipulation.  In the (surprisingly few) cases of insider trading that are prosecuted, it tends to be an individual (or small group) with early access to information that the broader market doesn't have being able to buy or sell ahead of the broader market.  Their individual sales are seldom if ever enough to noticeably move a stock price.  They're locking in profit or limiting a loss.  Manipulation might (but doesn't always) precede insider trading, if misinformation (or truth) is released for the purpose of creating a situation that can be profited from via a trade or trades. Insider trading is when you buy or sell an investment based on material, non-public information that gives you an unfair advantage over the rest of traders in that market.  Working for a company is one way that you might have such information, but whether it is insider trading is not contingent on you working there. You could use that information a long time after leaving the company. You don't even need to have worked there. If a friend/relative gave you non-public information because THEY work there, it is still insider trading. Calling insider trading theft is a pretty big stretch. I think it should remain illegal as it's not great for markets and undermines investor faith, if the people that bought stock from this guy wanted the stock they would have gotten it anyways. It is a simple case of breaking the wrong law. You can commit normal fraud all day long and the SEC won't life a finger. But even get within a hundred miles of a insider trading deal and they'll hit you like a ton of bricks.   It is easy an easy case to prove, there is no question as to it being illegal (even the janitor is expected to take a class on it), and the SEC was specifically set up to stop it after the Great Depression.  Really, it boggles my mind that anyone of that rank would think he can get away with it. Insiders are prevented from buying or selling shares except at certain periods right after information is disclosed publicly. But. People have bills to pay and kids to put through college and whatnot. So an insider can set up a plan where shares are sold on a specific schedule and they have no control over number of shares or timing. These plans (covered under rule 10b5-1) allow insiders to generate cash flow without immoderately benefiting from their inside information. Sales under these plans can mostly be ignored when trying to figure out the fortunes of a company from insider trades.