[whynotmaybe]

How would I do that?

Have "mycompany.com" and "marketing-mycompany.com"?

How

[svieira]

You've got it - subdomains are sufficient (IIRC). Something like notifications.mycompany.com for the important stuff and news.mycompany.com for the more marketing stuff (and of course someone.else.entirely for the the cold email list "well, surely this one little list couldn't hurt" ... nah, who am I kidding, never use those)

[butvacuum]

subdomains are not sufficient, unfortunately. I think the instance I'm thinking of is technically web/https (chrome's site safety feature where you can specify a domain as 3rd party content- so when something gets flagged uour entire domain doesn't get blacklisted)- but it's much easier to just grab another domain

[tracker1]

I think the point is that subdomains are fine, assuming you ARE using a separate IP address for said subdomains.

[gib444]

The majority of my spam from established companies are on subdomains of their main domains. Are they doing it wrong?

[stackskipton]

Subdomains are fine. Newsletter.mycompany.com and application.mycompany.com or even mycompany.com.

Most of time, I would use mycompany.com for company stuff and mycompany.net for Application DNS and EMails.