alea, the ATM affords the placement of shares without driving the price up.
The ATM, as far as price is concerned, provides a stable market for both the investor and for Wave. Were Wave to just start chucking shares onto Nasdaq, the price would fall. Were an investor to just start buying shares off the Nasdaq the price would rise. The ATM allows Wave and the buyer to set a price (largely determined by the prevailing market) and execute the transaction without causing market disruption.
That is what the ATM does. So the notion that an investor could take a significant position without affecting SP is to ignore the ATM. The ATM is there, the facility affords settlement at a fix price, the notion of buying pressure driving the price for a single large investor is false. That is what the ATM does ... price stability for potential investors.
The above content is my opinion.