I just put in my two weeks for a job I have help for about 7 months. When I started I received a 5k sign on bonus. When going back over the offer letter I see the following language:

"You are required to repay this bonus in full if you leave Company ABC voluntarily, or are terminated for cause, within the first 12 months of your employment"

And later in the letter:

"This letter is not an employment contract and does not create an implied or expressed guarantee of continued employment."

And then even later:

"Your signature indicates that you have accepted the offer with its contingencies"

So if they say that it is not a employment contract but say my signature indicates I have accepted the offer with its contingencies, it seems they are having their cake and eating it too.

Bottom Line: By stating that it is not a employment contract do they give up their claim to the bonus repayment?

It is a contract for the sign on bonus, but not a employment contract that promises you any specific time frame of employment, For example a employment contract normally would give you a job for a specific period,often one year, for a certain pay. In this case no contracgt was set