At least one proposal has been received for each franchise.
The proposition has been widely criticised for offering nothing for something, with the NZRU refusing to cede any ownership while trying to inject outside capital into the game.
However, chief executive Steve Tew remained bullish.
"We're heartened by the interest shown which underlines the attractiveness of the franchises as a commercial proposition," he said. "Since this is a commercial process we're unable to release details on each proposal. However, given this was a step into the unknown we have every reason to be encouraged."
Tew said each proposal would be assessed for a shortlist of those to make formal offers.
"Our desire is to have any new licence holder in place for the 2013 Super rugby season. The exact timing of final decisions will mainly be determined by the complexity of the transition to the successful bidder, but we hope to be in a position to [decide] around the middle of this year."
A licensee's responsibilities will include management of the team both on-field and off-field, although the NZRU would still be responsible for contracting players and coaches.
The teams would have to remain New Zealand-based.
Meanwhile, the Otago Rugby Union has again deferred filing an application to liquidate until next Friday as it desperately searches for a recovery package. "We're certainly more hopeful than two weeks ago so that's good progress," Tew said.
"The options we are looking at are very complicated, there are many moving parts and all have to come together to ensure we have a viable plan. The extra week will give all parties the time to make final decisions."
Although the decision has been deferred, it's expected an announcement will be made mid-week.