The JPMorgan Active Growth ETF ( NYSEARCA:JGRO) delivered a 14.2% return over the past year, trailing the S&P 500's 17.9% gain by nearly 4 percentage points. For investors paying a 0.44% expense ratio for active management, underperformance raises a key question: what should you watch to understand whether this fund can close the gap? JGRO's $8.5 billion portfolio reveals a critical vulnerability through its concentration strategy. The fund's top three positions control over a quarter of assets, creating exposure to mega-cap technology headwinds.