Hello

I have two critical questions; I have been in germany through an IT Outsourcer, and had recently interviewed for a company. One of the interviewers mentioned that Indian IT firms have a tax agreement with authorities and thus offer much higher pay than local firms can, which I could not validate.  
In my case, I do pay all social security payments & have complete payroll transfer here.

The firm came back to me offering around 15% less than my current pay (for the role of a project manager), and now am confused if this is what the benchmark is in Germany.
Do such salary agreements exist or are they bluffing? Also, what would be a good benchmark pay for a Project Manager with overall 6+ years of experience?

Employees of those Companies which are registered in India such as Bosch India or TCS India, when they are on intra company transfer to Germany are exempt from contributing to social security. Hence this route works cheaper for them. This savings may be in form or higher salary. This is the only advantage to such companies.

So in these cases, they would not be contributing to renenversicherung? 
In my case am pretty sure that is being contributed to.

There are no. of internal arrangements between home companies and their off shore sites to have direct and indirect tax savings irrespective of your deductions/contributions being made .
Sometimes benefits are passed on and sometimes Indirectly kept by employer.But it is possible.

Arrangements, for example?