This is a question about ethics - not so much about legal issues. Hope I'm in the right place... Suppose my site runs a word translation service where upon a given user query it forwards the query to some other dictionary site wherever, and displays back the results it just obtained. Assume the site is rarely visited so bandwidth is not an issue. TOS on relevant sites are not clear on forbidding this, as far as I can comprehend legal-talk. Would it make any difference if the site is %100 free ? Would it matter if the site was making profit indirectly like from AdSense ? Any opinion would be appreciated. Thanks.
If your site depends on their service, you are doomed. They can ban your site. What will you do? Get their permissions. If it is Yahoo, Google, or Amazon. I will use their API, otherwise not.
Without requesting permission or having a clear ToS that gives permission to do so, it would be unethical to scrape the results and have them posted on your page. You are basically taking their work, code, processing time, and bandwidth and making it look like yours. Whether it is free or ad supported makes no difference. Sites offer free services to bring people to their site, not so you can take their traffic. Same with ads, the ads are there to monetize the site. By displaying the results on your site you take away that site's ability to earn revenue from visitors that would have seen those ads. Of course, if you have permission (or they have a publicly available API) then there is no ethics issue. Another alternative would be to have the input box on your site but have the results displayed on their site.