Arconic is a publically traded company. It is an off-shoot of a company called Alcoa that is fairly well known in the US because of its former sponsorship of NFL football games and an ad program at every two minute warning to the end of games that replayed great football moments. Anyway, they went public in 2016, the year before the fire. The lawsuit alleges that managers knew this product wasn't safe but continued to sell it up until right after the fire. Since the stock value took a big hit after the fire due to them making the product, the investors are suing to recover their losses under the argument that the company's management failed to disclose the risk of loss to the investors. The managers seem to be arguing that they didn't know and even if they did know it is not their responsibility as long as building codes allowed its use. I have read that there are 6 emails involving managers of the company that makes it clear that they very much knew this product was unsafe for building cladding prior to the fire and them taking it off the market. Now in theory, they could recover these losses from the managers or their insurance companies if they have E & O policies, but ultamately the only people who really make money off these type suits are the class-action lawyers.
Now all that said, there is a separate wrongful death lawsuit against 3 US companies filed in Philadelphia related to the fire---GE whose appliance short-circuited and started the fire, Arconic for making the cladding, and Celotex who made the highly flammable insulation under the cladding. Even if any 1 or 2 o fthe companies went other (which they won't), the third could still be held liable for the full damages.