Hi Mark,
According to VectorWorks:
E Series licenses are single seat and are activated online. When purchasing an E Series license, you are provided with a serial number and download link via email. You can download an E Series onto two computers, but you can only actively use your software on one device at a time. You do not need an internet connection to use this type of license; however, you must connect to the internet at least once every 30 days to maintain your license’s active status.
https://www.vectorworks.net/company/purchasing-policy
They have temporarily increased it to (3) machines - per this Vectorwork employee's post:
By jblock
March 16
Working from home or remotely often requires resources that are typically stored on an office network or in another location. To limit disruptions, you will want to make sure that you have access to Vectorworks before working in a remote environment. The first thing you need to know is what type of license you own.
If your Vectorworks serial number starts with “E” (Series E), you have an online activated license. This means the license must be activated while connected to the internet. There are also a limited number of activations for each Series E license.
With Series E licenses, you may activate the software on two machines and only use Vectorworks on one at a time. If you plan on installing Vectorworks on a temporary computer, you will be granted a temporary activation to prevent any downtime. If you are permanently switching machines, you will want to make sure that you uninstall Vectorworks from the previous computer first.
Once it is activated online, you can use Vectorworks for up to 90 days without an internet connection. After 90 days, Vectorworks will need to activate again. Keep in mind that any changes to your machine configuration (changing hardware, upgrading your operating system) may force Vectorworks to activate again, even if within the 90 days.
*With the ongoing and ever-changing developments related to the coronavirus (COVID-19), we wanted to increase the ease of transitioning to a remote or work-from-home environment. In order to help, we are temporarily increasing the number of activations of Vectorworks Series E licenses by one. We intend to make this additional flexibility available for the next 90 days, while we monitor the situation globally.