Following similar initiatives from drug companies such as Eli Lilly, Merck and GlaxoSmithKline last year, the pharmaceutical giant Pfizer announced on 9 February that it will publicly disclose its compensation of US clinical investigators.

The voluntary move comes as lawmakers are pushing for increased transparency of the financial ties between doctors and drug companies. In January, US Senator Charles Grassley of Iowa and others introduced the Physician Payment Sunshine Act of 2009, which would require all pharmaceutical, biotechnology and medical supply companies that receive financial support through Medicare, Medicaid or the State Children's Health Insurance Program (SCHIP) to disclose compensation—both payments and nonmonetary gifts—given to physicians or medical practices.

Pfizer plans to disclose its compensation to doctors, clinical investigators and other healthcare professionals for speaking engagements, consulting and clinical trials from 1 July 2009 and onward. However, although Pfizer will report compensations totaling more than $500 a year, Grassley wants to require medical companies to disclose payments exceeding $100.

Grassley is also working to expose potential conflicts of interest for researchers who receive US National Institutes of Health (NIH) grants. On 5 February, Grassley co-sponsored an amendment to the economic recovery bill that would require principal investigators who receive NIH grants over $250,000 to report significant financial interests in companies supporting the work and explain how they would protect against possible conflicts of interest. The amendment was not included in the final bill that legislators passed, but Grassley will continue to pursue this issue.