Companies will have to change the way acquisition costs are handled under new accounting rules a move that will hit profits and could damp the urge for mergers.
Fees charged by investment bankers, lawyers and accountants are currently bundled into the overall cost of a takeover and go on the balance sheet as part of goodwill the accounting catch-all term used to cover the difference between the price paid and the actual value of the assets.
Separating the fees will force companies to book a one-off expense for each deal, denting their net income for that period.
Deal fees vary, but the International Accounting Standards Board said they work out on average at about 1.5 per cent of each transaction.
Global deal volume reached a record of more than $4,840 billion last year, according to Dealogic, the data provider. About three-quarters of those deals would have been accounted for under either the IASBs international financial reporting standards or US rules.
The new accounting standard will apply to companies following both systems because it is the first to be developed jointly by the IASB and the US Financial Accounting Standards Board. Companies following US GAAP will have to adopt the standard by the end of this year, while those reporting under international rules have until July 2009.
Although not 100 per cent identical, the two boards worked to reach agreement not just on concepts and principles, but also on using the same wording, said Mary Tokar, head of international financial reporting at KPMG.
The main difference is in the treatment of businesses controlled but not fully owned by the parent company. The US version will force companies to include goodwill even for the part of a business that they do not fully own, while the IASB allows groups a choice.
Peter Holgate, senior technical partner at PwC, said: It is a big shame that these are not exactly the same standard but if we can get this close on one of the most difficult topics in accounting, it bodes well for the future of convergence.
The average annual value of global M&A has been equivalent to between 8 and 10 per cent of total market capitalisation over the past decade.
The IASB and FASB have a six-year-old agreement to work towards converging practices to create a single set of global rules.
More than 100 countries either follow or plan to adopt the IASBs standards, including Japan, South Korea and India.
The new standard builds more closely upon IFRS practices, meaning that US companies face the biggest changes.