This excerpt taken from the NDAQ 8-K filed Feb 20, 2008.
Software revenue recognition
In its Technology operations, OMX enters into sales arrangements with customers for software programs, implementation of software, support and other post-contract customer support (PCS) services. Further, the Technology operations enter into certain hosting arrangements with certain of its customers.
Under IFRS, OMX recognizes revenue for its software and the implementation projects under the percentage of completion method. The support and hosting services revenue are recognized ratably over the service period. Other services are recognized when the service was performed. A variable fee arrangement is recognized when actual usage has been established.
Under U.S. GAAP, the rules for revenue recognition under multiple-element arrangements are detailed and prescriptive. These rules include the requirement that revenues be allocated to the respective elements of such an arrangement on the basis of objective and reliable evidence of fair value, preferably Vendor Specific Objective Evidence (VSOE), for each element. Statement of Position 97-2 Software Revenue Recognition (SOP 97-2) sets out precise requirements for establishing VSOE for valuing elements of certain multiple-element arrangements. When VSOE for individual elements of an arrangement cannot be established in accordance with SOP 97-2, revenue is generally deferred and recognized over the term of the final element.
Under U.S. GAAP, OMX did not have VSOE for certain elements of certain multiple-element arrangements with customers. The terms of these arrangements with customers include, among other terms, the provision of hosting services and on-going customer support (known as PCS under SOP 97-2). As a consequence of the terms of these arrangements, under U.S. GAAP, the total revenue for a customer under a customer contract is recognized over the total customer service period.