That’s an interesting argument. It may be that the corporate by-laws permit such a practice if it is legal in the state where the company is chartered. It sounds like what Company A sold was intellectual property rights but does not intend to cease operations. If it was done with the intention of fleecing the investors the investors may have some legal recourse, but if the proceeds from sale are being held or used for another legit purpose, the investors may have to wait and hope.
My understanding of what happened is this: Company A developed a medically-related procedure using proprietary machines designed for its own use. Company A opened a number of retail offices for people to come in and take the treatment for a fee. Company B then somehow became the owners of all machines, offices, and other assets, leaving Company A with no assets and a set of very unhappy investors who lost their investments. I am having a lot of trouble finding this reasonable, or even lawful (I am not a lawyer).