It will cost 250 million credits and will be sold everywhere battleships are sold. It will replace the ship's scanner (hence you won't be able to use Spyglass Scanner, sorry, but that's a necessary sacrifice). Scanner stats will reflect that it's the best scanner available, equal to Spyglass, so there won't be any reason to keep another scanner aboard.
License MUST be mounted, yes. For your own safety.
Factions will get up to 4 licenses for free depending on their size, longevity, and system ownership status. Starting factions and smaller factions will get 1 license for free. You can buy more yourself if needed.
Limitation is: 1 license (and 1 battleship) per player. No battleships without licenses. The rule will [i]not[.i] be enforced for the first two months since it's introduced, so you'll have plenty of time to think what to do with your excessive battleships, or to trade and get the money necessary to buy a license.
Multiple accounts: first of all, I'd like to warn that creating new accounts just to own more battleships is unacceptable. Violators of this rule will be banned for prolonged periods of time. I suppose that we could allow one person to own two battleships on two accounts in exceptional cases, but only if he/she got 4 other ships + 1 battleship on each of the accounts. So, long-time players who got many role-playing characters will have a chance to own two battleships.