Member States shall also lay down rules which govern the conduct of bids, at least as regards the following:

1. (a)

   the lapsing of bids;

2. (b)

   the revision of bids;

3. (c)

   competing bids;

4. (d)

   the disclosure of the results of bids;

5. (e)

   the irrevocability of bids and the conditions permitted.