Nat. Biotechnol. 26, 1227–1233 (2008); published online 7 November 2008; corrected after print 9 February 2009

In the version of this article initially published, in Figure 5, the $2.40 billion pie section was mislabeled as Rituxan. It should be Procrit. The error has been corrected in the PDF and HTML versions of this article.