Why am I getting fake IM requests in Yahoo Mail?

Every now and then when I log into my yahoo mail, I get a request to add someone. I know it's no one I know, and it's obviously a bot.

I ended up changing my yahoo email address (which was a pain because I have so many log-ins that I use this mail for). I don't post my email address anywhere, but I am still getting these stupid messages.

I also have been reporting them as spam and ignoring them. I would get something from Yahoo saying "thanks" but then I see no solution. Another bot will try to contact me.

I have been doing virus checks an came up with nothing. I mainly go to amazon, ebay, what not.

Sometimes I get this at school too (I remember to uncheck remember my password).

Please help.

1. Use Gmail
2. ???
3. Profit

Spam?
We have separate school email and we used to sign eachother up for spam.
Mainly Groupon.
I know requests aren't the same, though..
Contact Yahoo?

I had that problem too, I finally figured out to to shut off the IM. Click the button next to your contact list, and it will put you offline.

Thanks Ninja :)