Company name: Apertio
Where it's based: N/A
When it was founded: 2002
What year it was a Fierce 15: 2006
Website: N/A

Why it was a Fierce 15: Apertio pounced on the IMS market early and established itself as the largest independent provider of subscriber-centric networks, tying up a number of deals with Tier 1 operators including Orange, T-Mobile and Vodafone. Click here for more.

What has happened since it was awarded the Fierce 15: Nokia Siemens Networks acquired Apertio in February 2008 to strengthen its "ability to help customers simplify their networks and manage their key asset--subscriber data," according to NSN.