A fresh new avenue for Google to kill your SaaS startup
A website can be ruined if it gets blacklisted. It is more possible where we allow users to upload content.
A lot of the cases of blacklisting that I found while researching this issue were caused by SaaS customers unknowingly uploading malicious files onto servers. Those files are harmless to the systems themselves, but their very existence can cause the whole domain to be blacklisted. Anything that your users upload onto your apps should be hosted outside your main domains. For example: use companyusercontent.com to store files uploaded by customers.