Q: Can the lock box be used by all players?
A: Yes. The lock box is shared between players, and the active player may use the new bonuses it provides (Stash and Retrieve).
Q: Does the lock box stay in play for the entire campaign?
A: Yes. At the end of this case, you will return the restriction (card 22) to the deck, but you will get to keep the lock box and bonuses for the remainder of the campaign.
Q: What happens if we have to lose several ideas due to an event and we have no ideas in our supply but some in the lock box?
A: When the general and player supplies of ideas are empty, the lock box protects you. Account for each idea you are required to discard in order. For example: if you must remove 3 ideas due to the Sabotage event and have none in your supply, but 2 in the lock box, return 1 idea to the general supply from the lock box (for the 1st idea), then remove that idea (now in your supply) from the game (for the 2nd idea), and then return the remaining idea from the lock box to the general supply (for the 3rd idea).