Combining different algorithms submitted to the Third International Fingerprint Verification Competition (FVC2004) is studied. For this work, the matching results of more than 40 fingerprint systems from both academy and industry are available on standard benchmark data. In particular, we concentrate on score-level fusion of the different algorithms, studying the correlation between them by using feature-subset-selection techniques. Based on the general algorithmic descriptions provided by the participants, some interesting experimental findings are obtained.