Not true. Properly prepared and characterized polyclonal antibodies are excellent reagents and when affinity purified they can easily compete with monoclonal antibodies in most applications. Because polyclonal antibodies contain antibodies to multiple recognition sites (epitopes) on an antigen, the apparent affinity and avidity of antigen-antibody interactions is very high. The result is greater sensitivity, which also means that the antigen is more likely to be recognized even after denaturation or proteolytic processing. This is an important consideration in applications such as immunoblotting from denaturing gels such as SDS-PAGE and in immunohistochemistry on fixed tissue sections. Polyclonal antibodies are excellent for use in immunoassays where high sensitivity is required and are frequently the preferred reagent for immunoprecipitation techniques and activity neutralization assays. Affinity Biologicals has had good success using it's polyclonal antibodies immobilized to resins to specifically immuno-deplete target proteins from citrated plasma and the purification of target proteins from the resins in high purity with excellent recovery of activity. For reasons of price and performance polyclonal antibodies are often the reagents of choice.