The test for insider trading is based on the reasonable man standard; no "guarantee" of going up or down is required.
The test is whether a reasonable man who had the same "material, non-public" information as the BP would be likely to buy or sell the stock in question if he had had the same non-public information.
So here is the test: If an ordinary investor like you or me had signed an NDA and learned in early Sept. how many stage IV NSCLC patients were still alive 13 months after dosing, and how healthy they still were in mid-Sept., and how well Bavi is doing in the related pancreatic and liver trials, would that information be likely to induce us to buy the stock after it fell it $0.84 on news that there had been a coding error in the investigational drug treatment groups?
If the answer is "yes", if knowing confidential, non-public clinical details of how well Bavi was performing in mid Sept in multiple contexts, would be meaningful to a reasonable man's decision to buy the stock when it fell by 80%, then there is a legal basis for an insider trading lawsuit.
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