A control circuit is included in a first die of a stacked semiconductor device. The first die further includes a transistor that is electrically connected to the control circuit. The transistor is configured to be controlled by the control circuit to selectively block a die-to-die interconnect. In this way, the die-to-die interconnect may be selectively blocked to isolate the first die and a second die of the stacked semiconductor device for independent testing after bonding. This may increase the effectiveness of a testing to identify and isolate defects in the first die or the second die, which may further increase the effectiveness of performing rework or repair on the stacked semiconductor device.