When licences for spectrum are being initially offered, auctions can create competition for spectrum, however it is often the case that the successful licensee is precluded from trading the licence at anytime afterward. Continuous reselling of spectrum becomes possible when a secondary market operated in respect of either spectrum that has been auctioned or of spectrum allocated initially by administrative methods but which is now been cleared for trading. When a secondary market is combined with flexibility in spectrum use, licences can be deployed by the original licensee or, after a trade, by another firm in a new innovative use. Auctions alone merely introduce an initial market-based selection by organizations that will exercise highly specified spectrum usage rights, whereas secondary trading seeks to develop a primarily market-based solution both for spectrum assignment and for spectrum allocation, on the condition that flexibility in use is permitted.
In this section, we discuss how to define the right of access to spectrum which are auctioned or trading (4.6.1), a major component of which relate to freedom from interference from other spectrum users, and prohibitions on causing interference to them (4.6.2). Secondary trading also raises issues of market power (4.6.3) and requires procedures to facilitate or enable transfer of ownership (4.6.4). Finally, how has trading worked out in practice (4.6.5).