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(with #*$!x being the adsense ID)
but regardless of teh above, what happen if users start to use your custom search and post links to your custom search engine in forums and others?
that would not really be pre-populating the searchbox: the search box would be bypassed, it would be a direct link to the google page
Except for related Google queries, all search queries (including queries entered into an Ad search box) must originate from individual human end users inputting data directly into a Search Box (or Ad search box, as applicable) on Your Property(ies).
well google adsense filter would not work in this case because it is not about prepopulating the search box. Besides the ads are shown on google custom search pages directly (the domain name is google itself), so no way to filter this anyway.
so if it is against tos, what about links to my custom search made by users, or other persons with ill intent?