US Patent 11926926 Libraries of genetic packages comprising novel HC CDR3 designs

Provided are compositions and methods for preparing and identifying antibodies having CDR3s that vary in sequence and in length from very short to very long which in certain embodiments may bind to a carbohydrate moiety or the active site of an enzyme. Libraries coding for antibodies with the CDR3s are also provided. The libraries can be provided by modifying a pre-existing nucleic acid library.