A Chinese robot vacuum company digs up “hidden evidence” to successfully invalidate a patent owned by its biggest competitor. Highlights Background With the growth of online shopping, it is easier than ever to provide evidence of a sale when the product is still being sold on the market. But what if the product is no longer being sold? It’s much more challenging to prove the original disclosure date for a secondhand item, especially in a jurisdiction like China, which has very stringent notarization and legalization1 requirements for introducing evidence into a proceeding. The case below demonstrates an example of how one major Chinese robot company successfully dug up and introduced…