Very simple - Since Leo has access to trial data or applications for drug candidates that we do not until it is released to the public, that is/would be considered as insider trading. Now once the info has been released to the public, then sure he could buy on the open market. But while we have the BTD for B-OM ongoing and also the P trial results, there is no way he could buy on the open market - people would be screaming Insider Trading violation until those 2 things have been settled. Plus, you also have the 20 Signed CDA's which only he (and possibly the Dr.'s know who those companies are), which creates another whole aspect of "Inside Information" since we are not aware of the context of the meetings they may be having with those companies.