Last year, Genentech, a global leader in the manufacture of genetically engineered drugs, had sales of about $5.5 billion. A "biotech drug" is one that uses a protein to treat a particular disorder: to make its protein-based drugs, which include cancer treatments and a human growth hormone, Genentech must grow vast quantities of therapeutic proteins in host cells and then harvest them.

The company can ferment approximately 280,000 liters of cell culture at any one time at its various manufacturing plants.