hi YASMCP,
you can check reply of QatariSun at following link

http://www.qatarliving.com/node/235573

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qatarisun said saleemshajahan1.if you are ...
saleemshajahan
1.if you are on business visa, you don't have any sponsor, therefore you don't need any NOC from anybody.
2.as per your "secondly" and "finally", they are different CASES, but the NOC letter in the SAME: NO Objection Certificate.
3.you say:"if you are a doha resident for more than a year..". and what about those who are a doha residents for less than a year? don't they need a NOC letter? they DO need it, and again it will be exactly as same NOC letter as in first two cases.
The idea of the NOC letter is to confirm, that the current sponsor doesn't mind you to work for another company. that's it. then it's up to you: to stay in the country and to move to another company right away, or to leave Qatar and to find another job from your home country. Your previous employer and his NOC letter have nothing to do with that.

and you, innocent, can try to obtain a NOC letter from your ex-sponsor. Contact them, ask nicely, maybe they will grant it to you. then you can find another job and come back in qatar.

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“You become responsible forever for what you have tamed”. Antoine de Saint-Exupéry
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Hope that will help.

Regards //