That is an absolute falsehood.
Hypothetical Example:
1)Warren Buffet is diagnosed with terminal brain cancer
2)He is on "medical leave" to have tumor removed, but only for palliation of symptoms
3) Board says "he just had to have a toenail removed, that's all"
4) Shareholders therefore are not allowed to make decisions based on actual facts
Would you still argue your point as stated above?
but that isn't what happened.
Once he is on medical leave don't need to disclose more details or give a blow by blow of what the minutia of the issue is. The fact that someone is on a medical leave and not taking "sick days" means that it is a serious medical issue. Whether that person is going to die in 2 months or 10 years from now is immaterial. Right now, that person isn't running the company. If you think that is critical for your investment, you know.
Likewise, until the company has solid information on long term impact, it is also irresponsible to issue incomplete, extremely speculative information. What the specific, accurate prognosis is of the surgery will not be known until a while after the transplant when the immune suppressant drugs have taken hold (or not).
If they knowingly misled the public with statements like "it's a simple hormone imbalance" when indeed it was known to them that such was not the truth, well then they have completely failed at their fiduciary responsibility as board members (and yes, I'm quite familiar with those responsibilities) and there will be legal consequences eventually I'm quite sure, which further depress shareholder value.
The key factor above is the deception. It has very little to do with health specifics or expanding privacy boundaries.
If that was the most recent attempt as a diagnosis they had at the time there is no problem. If they lied ( because knew that would keep the stock price up) then they are in trouble. However, the liver problem could have been another cascade failure that only surfaced after they started to correct for the hormone inbalance. When one part of the body's systems is screwed up it is harder to diagnose the problems other parts may be having.
So if his weight came back and his liver was still off they could then surface a second problem.
Additionally, a improperly working liver can also cause a hormone imbalance. If Jobs has an unusual (or just bad for hormones) diet then first will try to correct that. (Vegan isn't mainstream and while not necessarily bad, if Jobs was eating badly/unbalanced ) Jumping to the conclusion need to "buy" a new liver is a huge jump (and more likely first step if surgeons are running the show). So perhaps, more so the optimistic diagnosis than what turned out to be a more accurate one. In complicated diagnosis the doctors always get it 100% right on their first stab? For a cold yeah. For multiple interdependent organ problems.. often not.
If boards got sued for plausible diagnosis of the market that later turned out not to be really true once have done deeper research and got better information, then the vast majority of them would be in deep trouble. They are not.
Companies need to be absolutely precise as to what has happened. There is a tension where many who invest want companies to have perfect reporting about what is going to happen in the future. (because they price in future earnings from 2-3 years from now into the current price ... dubious when dig into the practical accuracy of that. )
P.S. I think folks are leaping to the "deliberate lie" track because the Jan. 5th it is a "doctors think ... solution is easy" and then less than a couple months from that later: new liver (or new partial liver). The hormone imbalance was more a symptom than the root cause.
The express track to getting the operation does reflect that it was his #1 priority.
http://www.apple.com/pr/library/2009/01/05sjletter.html
Jacked up liver can throw an imbalance. So still plausibly true.
The twisted part is "the solution is easy". I have a suspicion that the doctors didn't spin it as "easy" (or if did, got better doctors later).
All of which was followed by the 14th " it is way more complex than I thought"
http://www.apple.com/pr/library/2009/01/14advisory.html
Seems much more plausible that Steve was fooling himself much more than trying to fool investors. Optimistically thinking could
eat his way out of the problem rather than go under the knife. Push come to shove though, fessed up (the situation is very jacked up ... which is all the detail really necessary) and went on leave.