Industry Canada, the authority charged with radio spectrum allocation and assignment in Canada, administered a Combinatorial Clock Auction in 2013 whereby a sizable number of spectrum licenses were awarded to a handful of telecommunications operators to provide 4G cellular service throughout the Canadian provinces. The auction consisted of two main stages: the Allocation stage and the Assignment stage; in turn the allocation stage was further divided in two: the Clock Rounds and the Supplementary Round. The 700 MHz auction in 2014 was organised in 56 products which corresponded to 14 geographical areas with 4 sets of bands in each area (three bands with two blocks each, known as generic, and one band with a single paired block) and had all bidders bidding during the Clock rounds and in the Supplementary round. In the Assignment stage only those bidders who won generic licences in the Allocation stage got to bid on specific targeted licenses. This paper analyses the results from Canada's 700 MHz auction in an attempt to unlock main aspects of bidders' strategic bidding. It uses publicly available data posted by Industry Canada which follow every bidder's demand history throughout the auction represented by the round-to-round demanded bundles and the aggregate amount bid on for each bundle.

The purpose of this paper is to present a case study of Canada's 700 MHz spectrum auction, which took place at the beginning of 2014. The auction format adopted by the Canadian regulator was the Combinatorial Clock Auction (CCA). In Section 1, we review the band plan for Canada's 700 MHz spectrum auction. We discuss the reasons and benefits from the band plan that Industry Canada applied. Section 2 presents the background information about selected, qualified bidders in this auction. Further in Section 3 the main stage of the auction, the Clock Rounds, is described; two conditions designed to induce bidders to truthfully reveal their preferences are explained as their understanding is key to understanding the novelties of the CCA; in this section results from the Canadian auction are presented. In Section 4 we analyse the Clock Rounds stage in search for behavioural patterns observed from the auction history and data that can help us characterise the bidding strategies employed in the auction.

Using data provided by Industry Canada this paper seeks to understand what strategic bidding is in the 2014 700-MHz Canadian auction. The auction format is known as Combinatorial Clock. Its design seeks to induce truthful bidding, that is, a bidder is expected to bid in a way that at each round of the Clock Rounds stage her utility is maximised, and expected to reveal her true valuation for each bundle that make up her final bid in the Combinatorial stage.The Combinatorial Clock auction is an innovative auction design which aims to overcome some of the problems evidenced in the application of the Simultaneous Ascending auction, a format that has been widely popular for assigning radio spectrum to commercial providers of mobile communications services over the last 20 years.The paper uses publicly available data from the auction by Industry Canada. By focusing on the longest of the three auction stages, the Clock Rounds, it examines the evolution of several auction indexes as a means to devise an approach to understand bidders' strategic behaviour. It also uses a Revealed Preference theory framework to test whether bidders bidding was consistent with utility maximisation. When it is not, the paper analyses evidence to support claims of strategic behaviour.

The Combinatorial Clock Auction is a two-stage auction format, which has been used to sell spectrum licenses worldwide in the recent years. It draws on a number of elegant ideas inspired by economic theory. A revealed preference activity rule should provide incentives to bid straightforward, i.e., consistent with the bidders' valuations on a payoff-maximizing package, in each round of the clock phase. A second-price rule should set incentives to bid truthfully in both phases. If bidders respond to these incentives and bid straightforward in the clock phase and truthful in the second sealed-bid stage, then the auction is fully efficient. Unfortunately, bidders might neither bid straightforward in the clock phase nor truthful on all packages in the second sealed-bid stage due to strategic reasons or practical limitations. We introduce metrics based on Afriat's Efficiency Index to analyze straightforward bidding and report on empirical data from the lab and from the field in the British 4G auction in 2013 and the Canadian 700 MHz auction in 2014, where the bids were made public. The data provides evidence that bidders deviate significantly from straightforward bidding in the clock phase, which can restrict the bids they can submit in the supplementary phase. We show that such restrictions can have a significant negative impact on efficiency and revenue.

An international team of experts covers the pros and cons of different auction formats and lessons learned in the field.