"The reason I'm asking is if IPIX were to go belly up would shareholders of IPIX still be entitled to a stake in Squalus Medical?" Good question. The Squalus holding would be treated like any other asset in bankruptcy, but it depends on what type of bankruptcy is filed. Oversimplified there are 2 types, Chapters 7 and 11. In Chapter 7 ALL assets are liquidated and the show is closed, a la the Polymedix filing***. IPIX shareholders come up empty. The goal in Chapter 11 is to settle with creditors, avoiding multiple lawsuits, and save the show. SOME assets will typically need to be sold to accomplish that. Chapter 11 can be filed voluntarily or indirectly as a result of a petition by creditors. In Chapter 11 the Squalus holding would likely be sold IF they could find a willing buyer. IPIX holders wouldn't benefit directly but if the "new" Company survives Chapter 11 the proceeds from the sale may have assisted in that, so there could be an indirect benefit. Shareholders in the old company may be able to exchange their shares for shares in the new company, depending on the terms of the final settlement agreement.
***It might be interesting to note that Polymedix HAD TO sell the assets that IPIX bought to SOMEBODY. That fact has a bearing on the price of anything similarly situated. IPIX's bid has been described as a stalking horse bid. https://en.wikipedia.org/wiki/Stalking_horse_offer