It looks like you've tried to calculate the Theoretical...

It looks like you've tried to calculate the Theoretical Ex-Rights Price (TERP). Although there isn'tanything wrong with your method of calculation, I'm guessing some of your assumptions are out by a little bit. The TERP, as provided by SGH, is closer to $7.08.

Playing Devil's Advocate:
As I post this, SGH has now dipped to trading below the TERP. All other things being equal, this indicates a moderately negative market reaction to the acquisition. Thus, one might expect a reversal of this acquisition to be positive. Although I don't expect this to be case...

To provide some balance:
Of course, not all other things are equal: the market is down since the announcement, and there is a flood of sellers trying to take advantage of the rights issue (thereby pushing the SP down further). On a positive note, Grech has bought up over $11m under the offer and Fowlie over $3.5m, so a couple of the directors seem prepared to put some serious skin in the game.

It's my expectation that the acquisition will go through, and my guess that if it doesn't the SP will get knocked down. If it does go through, I'm not expecting much. But as Brierly59 succinctly put it, "the price has been bouncing around so much it's anyone's guess where it will go".