> AGIX – Most (all?) conferences allow you to submit a placeholder if you think you will have news before the event. So I don't think the above logic holds.<
The Jan 4 deadline for submitting an ACC abstract may be irrelevant for the reason you mention, but the companies could be negotiating with ACC as we speak about what can and can’t be said at next week’s JPM conference. If they are, it could be the source of a leak.