Bitcoin experienced a significant decline on May 13, driven by concentrated selling from large holders, known as whales, and increased pressure in the futures market. Whales, holding between 1,000 to 10,000 BTC, reduced their holdings by approximately 7,650 BTC, equivalent to $615.8 million at an average price of $80,500. This selling activity coincided with a drop in Bitcoin's price from $81,267 to $78,806 between 12:00 and 17:00 UTC. During this period, futures market activity intensified, with Open Interest rising by $589 million, indicating new leverage entering the market. Despite a subsequent attempt by futures traders to capture a rebound, Bitcoin only partially recovered, moving from $78,793 to $79,609 by 22:00 UTC. The overall market dynamics were marked by aggressive whale selling, which outweighed the gradual accumulation by smaller holders, resulting in a net positive balance of only 816 BTC, insufficient to reverse the decline.