[sonofgod]

Literally from googling, so not legal advice:

https://www.upcounsel.com/abandoned-trademark

A dead trademark is not always available for use or registration by someone else because the original registrant might still be using it, and thus retain common law trademark rights. Search the USPTO website to learn why the trademark was abandoned. You might be able to acquire the trademark depending on the circumstances of its abandonment.

Before using an abandoned trademark, speak to a trademark and branding attorney and find out why the application was abandoned.

You must clear the rights before using the mark.

If the mark has been abandoned for three to five years, most likely you're safe. But beware that a non-active mark in the USPTO database could still be in use by the original owner. Even if you prove that the original owner has no intention of using it again, you still risk legal problems.

Make sure to also check all countries where the mark was used.

[bizgrayson]

Thanks for the link!