https://www.reuters.com/article/us-lucid-motors-m-a-klein-stocks/lucid-motors-spac-skids-as-56-billion-valuation-sparks-bubble-concerns-idUSKBN2AN1RR >Shares of Churchill Capital IV Corp fell more than 40% on Tuesday, as its merger with electric vehicle maker Lucid Motors sparked concerns about the real worth of the company which has yet to start regular production.