As a hedge fund manager, losing money is not illegal. The only illegal thing he did was lie about it so that he could get them their money back.
It would've been perfectly legal for him to lose all his clients money in the hedge fund, make them aware of this fact, and reap the profits from his pharma business without dishing it out to his hedge fund clients.
As far as I can tell, Shkreli turned a technically legal "I fucked up and lost your money scenario" into a technically illegal I fucked up, lost your money, but got it back to you scenario.
If I was part of Shkreli's hedge fund, I would much prefer to be involved in the latter scenario than the former.
Sure, I could sue Shkreli to recoup some of my hedge fund losses, but this way they didn't need to.
You're missing the point; giving his investors 'their' money back was the thing he did that was unethical and illegal. If you're a fund manager and the value of your portfolio goes down after making bad bets, you can't just inject your own money into the fund to make it look like you have a positive track record so that you can solicit more outside funds.
He took some of Retrophin investors profits and used it to pay back his investors in MSMB. Those profits should have gone to Retrophin investors.
From the perspective of the hedge fund, this is a pretty bad spot to be in. Retrophin investors will be looking to be made whole for the money Shkreli gave to MSMB investors.
I would imagine that this is how Ponzi schemes start.
Definitely going to be interesting to hear the judges words during sentencing. I was listening to the Michelle Carter sentencing yesterday, as I was following that relatively closely. Now I'm waiting to see what happens here, but this is much more cut and dry than that case. I'm only interested because it's Shkreli.