Question: Im currently researching how to handle lead generation forms. 

I came across a website which has 3 slightly different forms for downloading a white paper, downloading an ebook, and downloading the trial.The trial download form is the shortes.

Trial Download fields:

* name
* company
* phone
* email

White paper form fields are the same but have 2 more fields:

* job positon
* country

The ebook form has trials form fields + state field.

I can not wrap my head around this. 

Why would they have those differences in forms? Does this strategy have a name?

Also, i want to add on this particular site, if you fill out a form once, the info you already entered is auto filed on the next form you would fill out.

So, if you get a trial first, you would only need to fill out 2 more fields for the white paper.

But who is to say that most people would first get the trial, and later a whitepaper? Does this even make sense?

Answer: 
Assuming there is a good reason for this (which we will never know):

If they have a **different expected audience** for each product, it may be that their business logic has dictated that they need to know the additional information for whitepapers - for marketing or sales reasons. This actually makes sense if they want to be able to say "349 companies have used our whitepapers to inform them of *X*".

It may also be that each item is handled by a **different department**, and so the information requirements have simply been given to the developers to include.

From a UX perspective, it is best to ask for as little information as possible, but **UX needs have to always be balanced against other business needs**.
This strategy looks like a reverse-common-sense implementation. The most guarded of my personal information is my phone number, followed by email, and then anything else from the list. 

If I had to do this, I'd tag the most valuable asset with direct contact information of the person downloading it, not the other way around.