SearchScene is not a scam. We genuinely donate 95% of all our profits to charity, in accordance with everyone's votes - read more about our voting system here.
We aim to be completely transparent and so we publish all our donation receipts, as proof of our donations, on this page (just scroll down and click on the link "See proof of donations", below any set of donations).
SearchScene is not the only chartitable search engine. However, very few other charitable search engines publish their actual donation receipts, which contain a receipt number, reference number or transaction ID that allows the donation to be traced. Many other charitable search engines produce reports or self-styled certificates - but these are not donation receipts and are therefore not proof of donations.
It is also worth noting that no other charitable search engine donates as much of their profits (95%) to charity as SearchScene does. You can read more about that here.