Yeah, it is legislated. Corporations Act 2001 and Corporations Regulation 2001. Go take a look at ASIC Regulatory Guide 196, particularly section 159. Certain transactions can be exempted from reporting, but that's not typical.
The price is falling because the company is close to running out of money, and the market does not know for sure whether funding will arrive before it does run out. Undoubtedly there are parties that would benefit from picking up the company or it's assets at a bargain basement price. The cost of getting an LNG export terminal project approved in the US is well above our present MC. Our other assets, such as the BH site and OSMR tech, add further to the company's value.