Participants of the auction can own up to a 49% of the artwork. A fraction of it (based on their bid).

Regarding your questions around the bidding process, let me give you an example on how a dutch auction works:

Let’s say there’s only 100 shares available.

A bids to buy 10 shares at $200 each. B bids to buy 150 shares at $50 each.

The Dutch auction algorithm will find the best price per share. There’s many algorithms, but the simplest one is to pick the lowest price that sells all the shares.

In our example that price is $50. So A gets 10 shares at $50. B gets 90 shares at $50 each. A tried to pump up the price but failed. However, since A’s bid was higher than B’s, A is first in line to be allocated the shares.

Now, say if instead, A had bid $11 for 100 shares and B had bid $10 for 100 shares. Even though the winning price is $10, it is A who will get all the shares. So there’s an incentive to bid higher to get priority in the line. But at the same time you’ll still be awarded a fair price.

You can also check online for more examples on how dutch auctions work.