Abstract: The Telecommunications Act of J996 divides entitlements to network elements between incumbents and recent entrants. This Article analyzes this mandatory sharing regime as a semicommons, a property regime which combines interacting elements of private and common property. The tele-semicommons exhibits problems of strategic behavior and requires complex governance rules to abate them. These problems are particularly acute when they impede needed change in the governance regime. The Article therefore suggests a greater role for sunset provisions in the mandatory sharing regime.