Is there an online service that provides public company information through a public API?
I don't know of any free API's for these data, but I'll provide what information I can. Compiling all of this information from the EDGAR system and exposing an interface to it requires a fair amount of work and maintenance, so it's usually market data companies that have the motivation and resources to provide such interfaces. I know of a few options that may or may not be close to what you're looking for. The SEC provides FTP access to the EDGAR system. You could download and parse the text files they provide. Yahoo Finance provides summary files of financial statements (e.g., GOOG) as well as links to the full statements in the EDGAR system. Once again, parsing may be your only option for these data. Xignite, a proprietary market data provider, provides a financial statement API. If you need these data for a commercial application, you could contact them and work something out. (Frankly, if you need these data for a commercial application, you're probably better off paying for the data) The Center for Research into Security Prices provides data from financial statements. I believe it's also exposed through several of their API's. As with most financial data, CRSP is sort of a gold standard, although I haven't personally used their API to fetch data from financial statements, so I can't speak for it specifically. This answer on StackOverflow mentions the quantmod R package and mergent. I can't vouch for either of those options personally. Unfortunately, you'll probably have to do some parsing unless you can find a paid data provider that's already compiled this information in a machine-readable format.
Good day! Did a little research by using oldest public company (Dutch East India Company, VOC, traded in Amsterdam Stock Exchange) as search criteria and found this lovely graph from http://www.businessinsider.com/rise-and-fall-of-united-east-india-2013-11?IR=T :  Why it is relevant? Below the image I found the source of data - Global Financial Data. I guess the answer to your question would be to go there: https://www.globalfinancialdata.com/index.html  Hope this helps and good luck in your search! "Here are some approaches you may value: Wolfram Alpha This is a search engine with a difference. It literally is connected to thousands of searchable databases, including financial databases. http://www.wolframalpha.com/input/?i=list+of+public+companies+ Just keep clicking the ""more"" button until you have them all.You can also get great company specific information there: http://www.wolframalpha.com/input/?i=NYSE%3ADIS&lk=1&a=ClashPrefs_*Financial.NYSE%3ADIS- Just keep clicking the ""more"" button until you have them all.Then the company it'self will have great information for investors too:  [http://thewaltdisneycompany.com/investors][3] (Just keep clicking the ""more"" button until you have them all.) Regards, Stephen" I don't think any open source trading project is going to offer trial or demo accounts. In fact, I'm not clear on what you mean by this. Are you looking for some example data sets so you can see how your algorithm would perform historically? If you contact whatever specific brokers that you'd like to interface with, they can provide things like connection tests, etc., but no one is going to let you do live trades on a trial or demo basis. For more information about setting this sort of thing up at home, here's a good link: < http://www.stat.cmu.edu/~abrock/algotrading/index.html >. It's not Python specific, but should give you a good idea of what to do. "Such data is typically only available from paid sources due to the amount of research involved in determining the identity of delisted securities, surviving entities in merger scenarios, company name changes, symbol changes, listing venue changes, research of all capital events such as splits, and to ensure that the data coverage is complete. Many stocks that are delisted from a major exchange due to financial difficulties are still publicly tradeable companies with their continuing to trade as ""OTC"" shares.  Some large companies even have periods where they traded for a period of their history as OTC.  This happened to NYSE:NAV (Navistar) from Feb 2007 to July 2008, where they were delisted due to accounting statement inaccuracies and auditor difficulties.   In the case of Macromedia, it was listed on NASDAQ 13 Dec 1993 and had its final day of trading on 2 Dec 2005.  It had one stock split (2:1) with ex-date of 16 Oct 1995 and no dividends were ever paid. Other companies are harder to find.  For example, the bankrupt General Motors (was NYSE:GM) became Motoros Liquidation Corp (OTC:MTLQQ) and traded that way for almost 21 months before finally delisting. In mergers, there are in two (or more) entities - one surviving entity and one (or more) delisted entity.  In demergers/spinoffs there are two (or more)  entities - one that continues the capital structure of the original company and the other newly formed spun-off entity.  Just using the names of the companies is no indication of its history. For example, due to monopoly considerations, AT&T were forced to spinoff multiple companies in 1984 and effectively became 75% smaller.  One of the companies they spunoff was Southwestern Bell Corporation, which became SBC Communications in 1995.  In 2005 SBC took over its former parent company and immediately changed its name to AT&T.  So now we have two AT&Ts - one that was delisted in 2005 and another that exists to this day. Disclosure: I am a co-owner of Norgate Data (Premium Data), a data vendor in this area." If you have access, factset and bloomberg have this.  However, these aren't standardized due to non-existent reporting regulations, therefore each company may choose to categorize regions differently.  This makes it difficult to work with a large universe, and you'll probably end up doing a large portion manually anyways. "For US equities, Edgar Online is where companies post their government filings to the SEC. On Google Finance, you would look at the ""SEC filings"" link on the page, and then find their 10K and 10Q documents, where that information is listed and already calculated. Many companies also have these same documents posted on their Investor Relations web pages." You can access financial statements contained within 10K and 10Q filings using Last10K.com's mobile app: Last10K.com/mobile Disclosure: I work for Last10K.com If it is Texas company, you can try doing a taxable entity search on the Texas Comptroller website. It's difficult to compile free information because the large providers are not yet permitted to provide bulk data downloads by their sources.  As better advertising revenue arrangements that mimic youtube become more prevalent, this will assuredly change, based upon the trend. The data is available at money.msn.com.  Here's an example for ASX:TSE.  You can compare that to shares outstanding here. They've been improving the site incrementally over time and have recently added extensive non-US data.  Non-US listings weren't available until about 5 years ago. I haven't used their screener for some years because I've built my own custom tools, but I will tell you that with a little PHP knowledge, you can build a custom screener with just a few pages of code; besides, it wouldn't surprise me if their screener has increased in power.  It may have the filter you seek already conveniently prepared. Based upon the trend, one day bulk data downloads will be available much like how they are for US equities on finviz.com.  To do your part to hasten that wonderful day, I recommend turning off your adblocker on money.msn and clicking on a worthy advertisement.  With enough revenue, a data provider may finally be seduced into entering into better arrangements.  I'd much rather prefer downloading in bulk unadulterated than maintain a custom screener. money.msn has been my go to site for mult-year financials for more than a decade.  They even provide limited 10-year data which also has been expanded slowly over the years. "Edgar Online has this information for companies under SEC regulations and they are reported in ""Form 4"" so that should help guide your search" I think Infochimps has what you are looking for: NYSE and NASDAQ. As another answer started, this information comes straight from an exchange and generally costs a fortune . . . However things change: IEX, a new exchange, recently opened and they are offering real time bid/ask data for free. Here's the API description: https://www.iextrading.com/developer/ This data should be good for active securities, but for securities less actively traded the numbers might be stale. How can I get quarterly information about private companies? Ask the owner(s).  Unelss you have a relationship and they're interested in helping you, they will likely tell you no as there's no compelling reason for them to do so.  It's a huge benefit of not taking a company public. Reuters has a service you can subscribe to that will give you lots of Financial information that is not readily available in common feeds.  One of the things you can find is the listing/delist dates of stocks.  There are tools to build custom reports.  That would be a report you could write.  You can probably get the data for free through their rss feeds and on their website, but the custom reports is a paid feature. FWIW re-listing(listings that have been delisted but return to a status that they can be listed again) is pretty rare.  And I can not think of too many(any actually) penny stocks that have grown to be listed on a major exchange. Credit cards have two revenue streams: So yes, the are making money from your daily use of the card.