Space X en Bourse : Un danger pour Wall Street et personne n'en parle

SpaceX is expected to go public soon, with an anticipated valuation of around $2 trillion, making it one of the largest capitalizations globally, comparable to Nvidia and Google. This valuation, however, highlights a broader issue: the disproportionate capitalization of companies that employ relatively few people, yet command market values equivalent to the GDP of entire nations. This phenomenon is largely driven by speculation and narrative in a market where rules for index inclusion have significantly evolved. Over the past decades, stock market indices like the S&P 500 and Nasdaq have transformed. They no longer represent the same sectors; formerly dominated by energy and value stocks, they are now heavily concentrated in technology. Moreover, rules were introduced after the dot-com bubble of 2000 to cap the representation of any single stock within an index, typically at 10-15%. This means that even if a company's capitalization continues to grow, its weight in the index is limited. This was evident with Nvidia, whose weight in the Nasdaq 100 was capped three years ago when it started representing too much of the index. Therefore, today's indices are essentially weighted averages and momentum-driven. When investors buy ETFs, they are investing in these rules-based, weighted averages, not necessarily a true reflection of market breadth. For a company like SpaceX to be introduced into an index, a minimum of 10% of its capital needs to be on the market, which raises concerns about liquidity. If everyone wants to sell their SpaceX shares, there might not be enough available on the market. However, lock-up periods mean the real pressure on the stock will only be visible several months after the IPO. The core issue that SpaceX brings to light is not unique to the company but is a global market reality. Stock market capitalization is defined as the share price multiplied by the number of available shares. Indices, however, consider the "real float"—shares available for trading on the secondary market after excluding those held by founders, large initial investors, or the state. This rule was implemented about 20 years ago to address liquidity problems where companies had huge capitalizations but very few shares were actually exchangeable daily. This created situations where small trading volumes could significantly move a stock's capitalization. This phenomenon is akin to illiquid small-cap stocks where a €10,000 purchase can move the capitalization by €1 million. The same principle, on a much larger scale, applies to today's ultra-concentrated mega-cap companies. The problem is exacerbated by a market momentum driven by ETFs, where everyone buys the same stocks. Additionally, many companies engage in share buybacks, further reducing the number of available shares (the float). This means that the "real" net float available for trading is often much smaller than what is publicly announced or used for index calculations. Instead of 80% of shares being available, perhaps only 30% are truly exchangeable daily. As long as there is a continuous inflow of money, this creates exponential growth and helps the market increase. However, this creates a significant risk: what happens when everyone wants to exit at the same time? The market lacks sufficient counterparties. Over the past 15 years, share buybacks have reduced the number of available shares while increased demand has funneled more and more money into the market. This combination, along with the concentration of momentum, creates the exponential growth and premium valuations seen today. For example, Apple's real float has halved in 12 years, meaning investors are buying into a much smaller pool of available shares, which undoubtedly contributes to its current high capitalization. This leads to two major concerns: 1. The "real floats" used for index calculations are inaccurate; more than half of the shares may not be truly available. In a market shock, this could lead to extreme volatility in major stocks and indices, contrary to the expectation of reduced volatility from ETF investments. 2. The market is becoming increasingly technical, driven by supply and demand dynamics of available shares rather than solely company fundamentals. This means traditional valuation metrics may become less relevant. The changes in index calculation rules since the dot-com era, including limits on single-stock representation, mean that comparing current market statistics to those of 20 or 30 years ago is misleading. Even with SpaceX's inclusion, limits will be imposed due to its limited real float. Many investors overlook the underlying mechanics and rules of how indices are constructed and how volatility is calculated. As long as there's no major event pushing everyone to exit simultaneously, the problem of insufficient exit liquidity remains hidden. However, investors should be prepared for such scenarios, not by predicting them, but by having a pre-planned reaction strategy. SpaceX merely highlights this long-standing, systemic issue in today's highly concentrated and illiquid market.