Minefields have friendly codes. The minefield's friendly code will be the same code as the planet that is owned by the owner of the minefield that is nearest the mines center. So if you laid a minefield at Nixon and you own Nixon and Nixon's friendly code is "Q1m" the minefield would have a code of "Q1m". Any starship with that friendly code would be able to travel through the minefield and not activate any mines. If the planet's friendly code is changed the minefield's code will change to match it. The minefield friendly code takes effect as soon as the mines are dropped.
Any ship in a web minefield that has a friendly code that matches the web minefield will not be drained by the web field.
A ship will not minesweep a minefield with a matching friendly code.
(Only works with HOST Version 3.20 or Better)