In this case the short seller will owe both the Siaf share (that must be bought back at some point before returned to the lender) and the Tri-way dividend share (at the ex date).
If the Tri-way divi share will not be tradable until the ipo, the shorter could be in trouble, imo. The only way to buy back the divi share would be through buying more Siaf-shares. That would hedge the position (similar 18.3 %) but would force you to short cover 2 Siaf shares for every Siaf share that is shorted. Probably a bad deal.
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