Every German shopper knows the letters UVP on a price tag: unverbindliche Preisempfehlung, the manufacturer’s non-binding recommended price. A shop may compare its own price with a higher manufacturer’s price only if that price is clearly labeled in this way. Vaguer terms such as list price are not allowed for this comparison, because they are ambiguous. Everyday German marks other figures in the same way. Lottery numbers come with Angaben ohne Gewähr, information without guarantee. Offers say freibleibend or Änderungen vorbehalten, subject to change. Section 145 of the Civil Code explains why such markers matter. Whoever offers a contract is bound by the offer, unless he has excluded being bound.