Roughly $2.3 trillion was erased from the combined market value of the Magnificent Seven in June as investors questioned whether massive AI infrastructure spending will deliver adequate returns. The selloff highlighted concentration risk in a rally driven by a handful of mega-cap tech stocks, with the Nasdaq Composite falling about 4.23% over the past month. BofA Global Research's Bubble Risk Indicator assigns the PHLX Semiconductor Sector Index a score of 0.91 and the Technology Select Sector Index a score of 0.82, signaling elevated valuation risks. The S&P 500's price-to-sales ratio has climbed to 3.22, far above its historical average of 1.84, according to LSEG's head of earnings research. Investors may consider defensive ETFs in healthcare, quality, value, and low-volatility categories to reduce concentration and add portfolio stability.