The present invention concerns methods and means for identifying, producing, and engineering neutralizing molecules against influenza A viruses, and to the neutralizing molecules produced. In particular, the invention concerns neutralizing molecules against various influenza A virus subtypes, including neutralizing antibodies against H5 and/or H3 and/or H1, such as, for example all of H1, H3, and H5 subtypes, and methods and means for making such molecules.