Confused: Buying after IPO is a complex instrument?

[2009]

Help please,

 

I tried to buy a stock tonight, Global E.

 

An announcement popped up saying," You account isn't set up for complex instruments. You need to fill out this form to set it up"

 

The form was to acknowledge the risks of these complex instruments.

 

It just IPOd yesterday. I don't see what is risky or what makes it a complex instrument.

 

Is it cos of the lock up period?

 

I wasn't using margin or buying options. I have been buying stock for 5 years. I always stay away from that stuff. I just like buying shares.