In “Functional Requirements of Bibliographic Records” (FRBR) are de-tailed 14 user generic tasks that should be made by a catalogue. In order to analyze how necessary is to implant a data modeling based on the FRBR, the execution on each generic task is studied in three shared catalogues: Fiction Finder, Open WorldCat and The European Library. Each task is executed on the basis of a same assumption search, evaluating later the efficiency of each one by means of the information of the bibliographic record, the data modeling used and the benefits of the catalogue. The efficiency in the accom-plishment is weighed in five levels. All tasks can be made in spite of not having implanted a model based on the FRBR, although 6 of the same ones need a change to be made at maximum level. This is considered a high percentage for being solely basic tasks.