Why does the application ask us to research similar inventions to our own?
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That is one of the first steps all inventors take to see if their idea is unique or "novel" -one of the patentability tests. It can be really tricky to see if your invention is novel. Don't be discouraged if you find products or devices that are similar, your idea could have its own unique twist that
is patentable.
Do your research carefully and identify the differences between your idea and the
similar inventions you find. You might even be inspired with new ideas after you see what products/devices are already publicly disclosed.
Check back to learn more about other patentability tests!