Brussels, 24/02/2003 (Agence Europe) - The American company IBM has received the go-ahead by the European commission for the take over of Rational Software, also an American firm. IBM develops, manufactures and markets computer systems, equipment, services and software, whereas Rational Software is a computer engineering services company. Both companies are also active in software for developers (software that helps programmers analyse, model, build, test and manage computer applications). The Commission noted that, on this market, IBM and Rational Software were present on different segments. The presence of powerful competitors on the market in question and the rapid rate of innovation on the markets, notably, are factors that urged the Commission to accept the transaction.