Legality of use of Yahoo! data on commercial website?

Officially, there is no explicit permission to use stock data from Yahoo in scripts.

However, in reality, there are tons of scripts in every language imaginable (PHP, Perl, .asp, java, ...etc.) that use that data all over the internet. Just do a Google search and see how many there are.

It seems Yahoo realize that many people are using the data in this way, and turn a blind eye to it.

If I were Yahoo, I would just legalize such use and get it over with, but I doubt that they themselves own this data: they probably get it from some other provider.

That's interesting, especially with Microsoft wanting to own Yahoo!

Well I'm still trying to get a straight answer from Yahoo regarding this. I'll report back once I get something. I sure hope there isn't a problem. I'm nearing completion of a massively complex financial news and data website, that of course, uses this data.

please update us regarding this issue

I am almost sure that it is *not* legal to use the Yahoo Data and it doesn't depend on Yahoo.

There is actually a copyright on the stock market data that belongs to the stock market companies (like euronext, I don't know the names for the north american ones). So the figures actually belongs to them. Yahoo (as any other websites that use such figures) are paying to display them, but only for their website.

So I believe that Yahoo won't bother you if you use their figures, but it could be that you will have problems with the stock exchange companies, to which you have not pay the license to use the figures.

That being said, I am not a specialist of stock echange (but I am launching a new website on economy)

It is definitely NOT legal to use it for anything other than personal reasons.

Instead of bugging the poor support you could just read the footnote of yahoo's historical data:

Historical chart data and daily updates provided by Commodity Systems, Inc. (CSI). International historical chart data, daily updates, fund summary, fund performance, dividend data and Morningstar Index data provided by Morningstar, Inc.. Fundamental company data provided by Capital IQ. Quotes and other information supplied by independent providers identified on the Yahoo! Finance partner page. Quotes are updated automatically, but will be turned off after 25 minutes of inactivity. Quotes are delayed at least 15 minutes. Real-Time continuous streaming quotes are available through our premium service. You may turn streaming quotes on or off. All information provided "as is" for informational purposes only, not intended for trading purposes or advice. Neither Yahoo! nor any of independent providers is liable for any informational errors, incompleteness, or delays, or for any actions taken in reliance on information contained herein. By accessing the Yahoo! site, you agree not to redistribute the information found therein.