Is it possible that there is a bad man inside the Trezor company who left a backdoor in the manufacturing process of a small number of wallets?
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You can even raise more general concern. Is it possible that there is a bad entity (located, let's say, in China) outside Trezor company that produces counterfeits of wallets? I would not answered negatively. Even if such company doesn't exist today it can appear tomorrow. Thus, it is always better to buy the stuff directly from brand.