- the two domains are independent and have separate owners
- the websites are hosted on different servers
So I don't understand how you expect to exert influence on the other website by means of a script. Even if you could, it might be possible to bypass your script.
Coming to an agreement with the owner seems to me to be the best solution.
I have to agree with BKBK. If the other site is getting data directly from your database, then you can just cut off access to the database. But if the other site is "screen-scraping" your data, there is nothing you can effectively do to prevent it. One thing that might slow them down would be to give a constantly changing ID to the container of the information on the page (div, span, table cell, etc) to throw off their script that grabs the data. But this isn't foolproof.
You don't say what country you are in. In the United States, copyright laws don't require a website to post a warning ("Unauthorized use is prohibited.") in order to claim ownership, and the threat of legal proceedings are usually enough to get a copy-cat website to stop unauthorized use of data. Sometimes, it has to go a little further and legal documents are filed with the court. But even if it goes all the way to trial, the offending website is usually either forced to stop using the data, or it is shut down.
In any case, to answer your original question, there is no "anti-copy" script that can stop unauthorized use of content. The content is sent to a client system, and that client system can either display it in a browser, or put the code into a string and manipulate it for display on another system.
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