Nortel received inquiries from 80 potential buyers and signed non-disclosure agreements with 14 of them as part of its preliminary efforts to find a suitable buyer.

The company received final bids from four purchasers this January and settled on the Microsoft offer in March because it represented the highest and best offer the court documents noted.

Domain Incite, a blog that covers the domain name space, that the $11.25 per address that Microsoft has agreed to pay is more than what one would expect to pay.

"Remember, there's no intellectual property or traffic associated with these addresses -- they're just routing numbers," Kevin Murphy, the blog's editor, noted.

Based on that price, the total value of the entire IPv4 address space is in excess of $48 billion, he noted.