When am I eligible to request a regularised job after working in private industry on contract basis

I am working in private industry through contract basis. I had 15 years experience in the company without leave.

Now I am seeking your opinion on whether I would be eligible to ask for a regularised job- should I write a leter to the company requesting the same.

Dear sir,
I am working in private industry through contract basis.i have 15 years experience in this company without leave .now i am asking you that i am eligible for job regularise req letter to the company.

It depends on the Private Company to decide whether to regularise you or not. Past Service of 15 years does not give you any right in this regard, you can only request for the same. Does the company have any policy in this regard or at least any precedent?