The answer is that yes, in the worst case scenario someone...

The answer is that yes, in the worst case scenario someone willing to put 15M shares on the market AT MARKET PRICE could make the share drop precipitously for a company such as Lake.

The average daily volume of trades is somewhere in the region of 3-5M shares. If you were to put 15M shares up for sale AT MARKET the trading would begin by selling a package of shares to the highest bidder (buyer) at the current price until bids at that price are exhausted (100's or thousands of shares) and the next highest bid (offer to buy) would then be the current market price and sales would exhaust those bids until the next highest bid takes over and so on until all of the 15M shares have been sold.

If you have a look at the current Bid/Offer list you'll see that this scenario would take the shares prices down a very deep rabbit hole.

Of course people would continue to bid for shares (especially those that see value in the company) but at every decreasing prices ('why pay more than you need to if this fool is willing to sell so cheap'). It is very unlikely that a company such as LKE would run out of bids before the 15M shares are all bought.

The reality, however, is that it would be a very stupid exercise as the value of the total 15M shares would be substantially reduced. You would make a lot less money than if you placed small packages on market to follow the CURRENT market price.

If you did this to purposely depress the price with the intent of buying in later at a lower price (akin to 'short-selling) it might provide some profit advantage (in that you could buy more than 15M shares for the money you now have for your original package, and wait for the price to rise again) however the regulators of the stock market would view this as market manipulation and bounce on you from a great height.

Oh, wait, ....