char concept a child in an orphanage was discovered to have magic&Drake potential (the finder was a dragon or his minions).

The child was watched until it was old enough to enroll in a magic school. (This causes the child too have to work a term with a corporation)

The person then is sent to an Ivy league school for magic study's.

They then work for a corporation as a wage mage.

Now for story and such could corporation be the dragon's organization? The limited SIN be attached to a corporation owned by the dragon?

Sure, it could. Plenty of dragons own corporations. However, once a dragon gets it claws on something they aren't very likely to let go, especially if they've specifically sought this character out. So what's the back story on how the character ends up in the shadows?

Who said they let go, maybe the char just thinks he is free.

2050 birth and abandonment to a orphanage
2055 covert discovery of possible talents
2060 talents blossom talented education
2067 sent to College
2071 investment used for the investor
2075 into the shadows, wanted

The concept was that a couple years before his death Dunkelzahn had been searching for Drakes and mages to be used for his ends. Some parts of his network kept working for awhile as some members tried to take control. One contact is a younger dragon that had aligned himself with Dunkelzahn and was in charge of the drake program.

I think the big D did do exactly that. Look into Ryan Mercury and Assets Inc (10 mercs is a place to start). So less a concept and more something that is actually in cannon. Anyway, there isn't anything wrong with what you have so far though at this point, if aligned with Dunkelzahn, the link is more likely to be through DIMR or the Draco Foundation rather than a corporation.
Keep in mind that Lowfyr and some of the other greats like Celedyr also have a cadre of drakes at their service so if you want to use an actual corporation those may be better choices.

The Draco Foundation is a corporation... though that's quibbling since non-profit corporations, private foundations and corporate for profit are all incorporated in different ways and only the corporate for profit stand a chance for a seat on the Corporate Council the way the bylaws are presently constructed.

In any event, I agree that the DIMR or Draco Foundation are both more likely to be his patron.
But we shouldn't forget Children of the Dragon- they too have the resources to be his patron.
Lastly, it isn't impossible that one of the corporation owning Dragons sink their teeth (er, um, take interest) into this character.
Lofwyr has fostered a lot of agents over the years- not all of whom even know they are working for him.

I guess what I started with the idea is that the corp based life modules could be an organization rather then a corp. However with that thought what to do about the limited SIN.

It's a negative quality.
In the karma phase after Real Life is completed you can buy it off.

Or swap it for another negative quality of equal value, either during character creation, or, with your GM permission, during game play. The last isn't a rule but a good GM would allow it, especially in the case of picking up something but finding it doesn't work with the concept.