Whales are individuals or companies who hold large amounts of bitcoins. Their buy/sell activity has the power to move the market.
When markets are highly volatile big players, referred as whales, are usually considered as the source behind the market volatility.
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Crypto products and NFTs are unregulated and can be highly risky. There may be no regulatory recourse for any loss from such transactions. Each investor must do his/her own research or seek independent advice if necessary before initiating any transactions in crypto products and NFTs.