As it is by no means a certainty I would put in a transfer ow ownership clause of most of her shares to you at that time and then another clause stating that she has the option of returning to the business after due diligence on her and an analysis of costs, revenues and time you've invested into the company in the interim.  You could value her re-entry into the business based on 2.5 times the value/profit when absent of the business multiplied by her requested ownership percentage and then that value could be paid as a percentage of her remuneration.

I think you have raised this question appropriately as it is always preferrable to discuss and agree uponj this type of issues before than later. A partnership agreement between you both should highlight this type of problem. I mean, it appaers to be a problem otherwise you won't be asking about it. The first thing that you should know is how confortable you will be when this happens if it happens. You partner will be gone for 2+ years and does this mean that all the burden and responsibilities will fall only on you? Won't she be able to collaborate via the extensive technological solutions that we have today. Does it require an 'in-loco' presence? That's a management issue because as far as representation she will still be a partner and therefore liable. Maybe you think you should be compensated more during this time frame? How do you feel about it? How does she feel about it. Ultimately, you should discuss how you plan to run things when this occurs and agree upon it in writing.

Like your friend is going overseas then this partnership will be called as overseas partnership ( if i am not wrong) then here comes the point that, is it possible to register a limited partnership for overseas? i think 'No'. Can anyone throw light on this?

that's a great point - I didn't think about a limited partnership.  Thank you!

Perhaps the best way to begin the business is as a limited partnership. She would contribute only financially until she returns to the States and is able or desires to become personally involved in the daily operations of the business. At that point, you could modify your entity filing to become a regular partnership. The attorney who prepares your partnership agreement can advise you on the pros and cons of a limited partnership vs a full partnership given your circumstances.

Depends. Is she the one financing the business (money) and you an industrial partner (actual work) ?. If everything is 50-50 finance and effort then you should talk to her about it. 6-12 months is a long time but its better to settle it out right before starting in this venture. lastly it also depends on what type of business it is. If it is an online business I believe she can still pull her weight.

You have to adress that in the partnership agreement because for my understanding when she will leave the country all the work load falls on you, so changes need to be made accordingly and don't feel embarrassed about it, it's business!