We propose the clock-proxy auction as a practical means for auctioning many related items. A clock auction phase is followed by a last-and-final proxy round. The approach combines the simple and transparent price discovery of the clock auction with the efficiency of the proxy auction. Linear...

In May 2008, Ofcom’s L-band auction concluded. This was Ofcom’s second combinatorial clock auction. The auction used an innovative format intended to encourage an efficient assignment of the 17 lots. Eight bidders competed for the lots. In sharp contrast to the first combinatorial clock...

In February 2008, Ofcom’s 10-40 GHz auction concluded. This was Ofcom’s first combinatorial clock auction. The auction used an innovative format intended to encourage an efficient assignment of the 27 lots. Each of the ten bidders won one or more lots. All 27 lots were assigned. This note...

I begin by describing some of the problems of the simultaneous ascending auction. Then I present the package clock auction, which retains the benefits, while addressing the weaknesses, of the simultaneous ascending auction. I emphasize two essential elements of the package clock auction: the...