No, Proteus Professional 8.12 is not freeware. It is a commercial software suite developed by Labcenter Electronics The "Free" Exception:
This version formally introduced cloud-based licensing, allowing remote management of seats and easier access for teams and educational institutions. proteus professional 8.12 free download
Includes mixed-mode SPICE simulation and the unique VSM (Virtual System Modelling), which allows for real-time co-simulation of microcontroller firmware with analog/digital hardware. No, Proteus Professional 8
Version 8.12 completed support for differential pairs with "pass-through" components, essential for high-speed signal integrity. essential for high-speed signal integrity.