Could add another $10($12B) to its book value, or not. Rumors and fantasies make Yahoo look like a cheap stock. But looks can be deceiving, rumors are for fools and fantasies for children. Your imagined value of the Asian assets is based on a rumor. Yahoo´s part in Alibaba Group is like the stock markets own little Area 51. Those who know aren´t talking and others are just guessing.
Framer - it's not a rumor when Silverlake has paid for a stake in Alibaba. You only have to decide if they underpaid or overpaid, and if the future has changed for better or worse from when they signed their deal. It seems to me unlikely that Ma will try to steal more like he did with Alipay, but that is always a concern.