The aim of a time-stamping system is to prove the existence of a digital document at a particular time in the past. Implemented time-stamping systems are generally based on a centralized server model. However, the unique server may represent a weakness for the system. In this paper, we propose a distributed time-stamping scheme which is more robust against a denial of service attack. Our protocol is based on a multisignature scheme. In order to be valid, time-stamps need to be accepted by at least λ servers. The interesting point is that the size of the time-stamp token does not depend on λ and that there is no publication process.