From the Help files (Visualization > GRAPHISOFT BIM Explorer):
BIM Explorer Trial License
ArchiCAD 16 includes a Trial License for GRAPHISOFT BIM Explorer. This Trial License works with FULL, TRIAL and EDU ArchiCADs as follows:
• Full functionality of GRAPHISOFT BIM Explorer for 30 days from the time that you export your first ArchiCAD model for BIMx
• You can only access the BIMx Community Site via Facebook
• Limited storage space on the site for your uploaded projects
• All uploaded projects are public (no option to password-protect or unlist them)
After the 30 days are up, you must purchase a BIM Explorer license from your distributor if you want to keep using it.
David