I am planning to create a website comparing flight prices. I am concerned about the legality of obtaining data from airline websites by screen scrapping them. The terms and conditions of these websites mention the need to have a license in order to use the software to download and use the data for commercial purposes. Here the question arises whether the price comparison engine, which does not generate direct income from this data but from advertising and partner programs, can be considered as commercial use of the data. On the other hand, even if it is not commercial use, is it legal to share such automatically downloaded data?
This is interesting because in many areas such comparison engines exist. These are e.g. price comparison engines for products, the mentioned flight prices, or bookmakers' odds. The conditions of using the data from these areas are the same as the conditions on airline websites. I don't think that all these websites have licenses for such things. Examples are http://www.azair.com/ or https://en.surebet.com/surebets. Both sites use data from dozens of sources and I find it hard to believe that they have licenses for all this.
To sum up, do you really need such licenses from each entity or are there any other solutions that allow to legally use this data in a price comparison engine?