Greater Boston’s life sciences real estate sector confronts unprecedented vacancy rates, reaching 29.7% including subleases, fueled by speculative construction exceeding tenant demand amid a biotech funding slowdown. New lab space deliveries outpace leases as venture capital funding dips to pandemic-era lows. These trends coincide with sharp biotech valuation declines and cautious investor sentiment amid federal policy uncertainties. Early-stage firms are downsizing footprints, underscoring a challenging market climate for life sciences infrastructure.