The Trade Desk (NASDAQ: TTD) shares suffered a brutal 38% plunge on Friday, closing at $54.23 in their steepest single-day drop on record. Year-to-date, the stock is now down 54%. TTD one-day stock price chart. Source: Google FinanceThe selloff erased massive market value, delivering a blow to top shareholder BlackRock, which holds 26.87 million shares, about 6.05% of the company, worth roughly $1.46 billion as of March 31, 2025.Why TTD share price is collapsing The collapse came after The Trade Desk’s seco ...