IntraLinks,a provider of secure content exchange systems sold on a software-as-a-service basis, has filed for an initial public offering.\nThe company's services are widely used in situations where privacy of data is highly sensitive, for example as private forums when negotiating terms of mergers and acquisitions.\nDetails of numbers of shares to be offered and price range have not been set but the progress of the float is certain to be watched by a technology market that has until recently been a desert in terms of IPOs but is now perceived as enjoying a strong rebound. Last week, for example, Cabot reported that almost a third of 79 IPO filings placed with the US's SEC were tech concerns.\nIn late 2009, CIO UK listed IntraLinks as a company to watch, writing that "IntraLinks is one of those companies you wonder why you had never heard of. The firm uses the SaaS model to host workspaces on demand. Companies in the process of M&A could employ it as a platform for securely swapping information, for example. It turns over more than $120m very quietly indeed but is now pushing hard for more publicity -- an IPO would help."