Duplicate companies are the product of HubSpot's setting to 'automatically create and associated companies with contacts' based on the emails sending domain of the contact.
The only way to full prevent this creating duplicate companies is to turn it off.
Duplicate companies are the product of HubSpot's setting to 'automatically create and associated companies with contacts' based on the emails sending domain of the contact.
The only way to full prevent this creating duplicate companies is to turn it off.