Well, that was fast. Just two days after we reported that Sprint was looking at the possibility of fully acquiring Clearwire, it filed papers to do just that – and at the hefty pricetag of $2.1 billion.

This offer effectively ends Sprint’s four year joint venture with Clearwire, which saw the start of a very promising nationwide WiMAX network that was never completed. If approved, Sprint will use Clearwire’s spectrum to continue its nationwide LTE roll out, and while we don’t expect that WiMAX will be turned off in the very near future, that is sure to be part of Sprint’s plans here.

Sprint already owns more than 50% of Clearwire, and will acquire the rest at $2.90 per share. Sprint has also agreed to provide interim financing to Clearwire to the tune of $800 million in order to keep Clearwire above water until the deal closes. Of course, all of this hinges on Softbank’s approval of the deal, as well as the completion of Softbank’s takeover of Sprint.

At least we’ll finally see that spectrum put to good use – eventually.