Bloomberg Intelligence has introduced a new tool called Blue Horseshoe that tracks the most bought and sold stocks by large active ETF portfolio managers on a daily basis. The tool ranks stocks, sectors, industries and countries by 1-day, 5-day and 30-day cumulative buying, and includes an Impact Score designed to measure the market-cap effect of purchases and highlight smaller names. The announcement said the product draws on holdings from active, transparent ETFs managed by firms including Capital Group, Fidelity, BlackRock and T. Rowe. Nintendo, Apple and Global Unichip were highlighted among names drawing attention, while internal testing cited one Japanese laser company that later rose 30% in the following month after topping the Impact Score.