It does not require a constant internet connection to verify a subscription.
The story behind Microsoft Office 2016 Pro Plus 16.0.4266.1001 VL X64 Microsoft Office 2016 Pro Plus 16.0.4266.1001 VL X64
Compared to its predecessor, Office 2013, Office 2016 Pro Plus offers several improvements and new features: It does not require a constant internet connection
While newer versions have since been released, the 2016 suite introduced several "modern" features that are still vital today: Microsoft Office 2016 Pro Plus 16.0.4266.1001 VL X64