Proving ownership of code with mercurial?

[Francesc Esplugas]

I've been working on a project for 3 months and now I've to prove  
somehow the ownership of all the code I've done.

All the code has been managed with Mercurial, so I can list the logs  
and diff's to show all my work but I want to explain somehow to the  
company that this code "is originally created by me". I understand  
that each time I make a commit to Mercurial this code gets signed but  
the company can say that I modified the repos an replaced all the  
commit authors with my name.

Is there any document out there that talk about how Mercurial manages  
data and how to prove trust of each commit made?

Thanks in advance,

Francesc

--
name. Francesc Esplugas i Martí
voice. +34 678.681.603