A recent example saw an Australian company offering to buy shares from Tower investors for $1 each. Stock & Share Trading Company's offer was about 90 cents below the market price of Tower shares at the time.
Stock & Share also made a low-ball offer to Vector shareholders in September.
The changes come after the Commerce Committee's recommendation last year that the Financial Markets Authority (FMA) be granted powers to capture low-ball offers.
"The new regulations will require greater disclosure requirements from a person or company that makes an offer, and introduce stronger rights and remedies for shareholders," Foss said.
Anyone making an offer will now have to state the market price or a fair estimate of the value of the shares being sought.
Minimum offer and cancellation periods will also have to be specified and failure to comply with an FMA order can result in a fine of up to $30,000.