You may want a few more explicit rules as this is backwards from the normal resource flow. For example, minimum number of shares per bid, maximum number of bitcoins per bid, bids are for all 20 shares.......
Your post is a little unclear, and perhaps the above will help you. I like the idea. If there is another thread with community rules for this type of reverse auction, include a link to that perhaps, ect.
Ok,
Thank you.
Everything is based on one share.
- minimum bid step is one share
- minimum shares for bid - one