Communications Minister Mitch Fifield has announced that TPG and Vodafone have snapped up the remaining blocks of 700MHz spectrum left over from the switch from analog to digital TV several years ago. TPG paid a hefty $1.2 billion for the spectrum, which is noteworthy because TPG doesn’t have a mobile network of its own yet.

TPG has been quietly buying spectrum licences for years and sitting on them, with expectations rife that the company would begin building its own 4G mobile network, rather than just reselling white label mobile products from other networks. TPG has talked this down, saying a network was still in research and development mode, but today finally showed its hand and told the ASX it would be building a network with 80% population coverage over the next three years with between 2000 and 2500 mobile towers.

The company told the ASX it would look to get about half a million subscribers.

Vodafone buying up some of the spectrum is also interesting in that one of the bigger rumours in the telecommunications industry would be that TPG would buy out Vodafone’s assets from its global parent companies. Either way, once TPG gets into mobile, it will be close to giving Telstra a run for its money as Australia’s largest telecommunications company. Telstra is more focused on becoming a global tech company, so it probably isn’t too concerned.