IWC Mark xii face

Hi,
I recently acquired a Mark xii. I wanted to know when the watch was made and if the factory serviced it. I called IWC and was told I couldn't have any info unless I sent it in for an "authentication". The watch is authentic, I don't need to pay them to tell me. I just need to know when it was serviced last, hopefully by them and what was done, so I can get it on a schedule like my other watches. Any ideas? I'm about to go back to my Rolex and sell this thing.