We analyze the extent to which patent pools (agreements where patent holders agree to license their intellectual property as a package) could be used as an institution to facilitate technology transactions in biotechnology. Patent pools have been used with success in the consumer electronics and other sectors but they are untested in biotechnology despite their transaction cost reducing potential. We suggest two explanations for the fact that patent pools have not been used in this industry. The first is that the current antitrust requirements are difficult to meet in biotechnology. The second is the availability of simpler alternatives that will often be more profitable to patent holders: aggregation of rights by one party and cross-licensing.