In short, as described on Fool Indices, it "was developed by The Motley Fool to define and track the largest, most liquid U.S. companies that have been recommended by the Fool’s analysts."

Source: https://seekingalpha.com/article/4578358-tmfc-etf-inflation-over-narrative-spurs-returns-not-long-term-buy?source=feed_all_articles

Motley Fool Asset Management LLC now owns 2,913 shares of the specialty retailer’s stock worth $257,000 after buying an additional 99 shares during the last quarter.

Source: https://www.etfdailynews.com/2023/01/10/etsy-inc-nasdaqetsy-shares-bought-by-fifth-third-bancorp/