https://www.reuters.com/article/us-deliveroo-ipo-preview/deliveroo-ipo-puts-londons-tech-credentials-to-the-test-idUSKBN2BM0GE >When food delivery firm Deliveroo joins the London stock market on Wednesday, it will be Britain's biggest listing in a decade, even though some of the country's leading investors - worth over $1 trillion between them - will be conspicuous by their absence.