If you do not know what it is for then why did you get it? Doing things you do not understand is a recipe for trouble.

If you have a 98 EIN, you have a Foreign Grantor Trust, which is a good thing. Whether you know it or not, you are a public bank or public banking utility. Social Security recognizes you as such and they want to keep you in a public banking position. Filing for a Foreign Grantor Trust is setting up your own Private Banking Trust. You should do some research into Private Banking and it may not hurt to see if the bank you do business with has a Trust Program. If they do, this is the best way to get to the FRB Trust we all want to get to. A Foreign Grantor Trust will always start with numbers beginning with 98. If I am not mistaken this private grantor trust is tax exempt also. It's not a bad thing to have but Admin is probably right. You should always do your research or ask questions before you jump into anything. Admin could have been kinder or used a different way of saying it. 

As I said, it came as part of a package and was not the main goal. My apologies if I came off snippy as well.