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the probability and discount rate are used to statistically estimate the net present value of future payments required on the Royalty Preferred Shares. The discount rate decreases as the payment obligation gets nearer which means that the liability $s increase. The probablity of actually having a marketable product increased from 35% to 42% for the first time since they have been booking this liability on Resverlogix.
If you read the footnote on the latest financial statement it adds some explanatory comments.
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