Costco Shares Slide to 29th in Trading Volume as High Valuation and Insider Selling Weigh on Momentum

On August 28, 2025, Costco (COST) closed with a 0.48% decline, trading at $945.58 with a volume of $1.96 billion, ranking 29th in market activity. Despite strong earnings and membership growth, the stock faces mounting pressure from multiple factors.

Analysts have downgraded the stock following mixed reactions to its Q3 2025 earnings report. While initial results spurred a 5% rally, the momentum faded as firms like Loop Capital and Evercore ISI reduced price targets. A rare downgrade from Erste Group Bank, citing a high valuation compared to peers, further weighed on sentiment. Costco’s trailing P/E of 53.7 and forward P/E of 52.2 remain significantly above the retail sector average of 27, raising concerns about sustainability.

Technical indicators also signal caution. The stock failed to surpass its February all-time high of $1,076 and crossed below both the 50-day and 200-day moving averages in July and August, forming a “death cross” pattern. This technical bearish signal suggests a potential continuation of downward momentum, with key support levels now at risk.

Insider selling has intensified over the past year, with executives including CEO Roland Michael Vachris and executive vice presidents Gary Millerchip and Claudine Adamo offloading shares. While individual sales are modest relative to total holdings, the consistent trend across eight consecutive quarters has raised investor skepticism about underlying confidence in the stock.

Query limit exceeded.