On December 23rd, Binance co-founder Changpeng Zhao tweeted yesterday, "Recently I have seen cases where some people receive cryptocurrencies by accepting private keys or hardware wallets. This is a bad idea because the giver still has access to these cryptocurrencies and should transfer the cryptocurrency to an address they own, or better yet, just ask the giver to send it to an address they own. Giving two people access to the same private key (or mnemonic) is a bad idea. When these cryptos are moved (or stolen by hackers), it is nearly impossible to prove who moved it (or hacked)."