you can legally ignore anything that is not a formal letter from court
This is very very much wrong.
Here’s what would probably happen:
You ignore the cease and desist
Opponent’s lawyer goes to a judge and gets a preliminary injunction
You must respond to it AND also cease doing whatever the cease and desist demanded.
Enjoy doing everything through the courts now, which will always cause higher costs than dealing with it privately. Especially if you aren’t 100% in the right.
This is very very much wrong.
Here’s what would probably happen:
Enjoy doing everything through the courts now, which will always cause higher costs than dealing with it privately. Especially if you aren’t 100% in the right.