On Mar. 4, 1997, President Clinton issued an executive order that banned federal funds for cloning experiments. This ban existed and no NIH money was used to pay for human embryonic stem cell research until President Bush speech of Aug. 9, 2001 when Bush agreed to allow funds to be used to study only those lines that existed before he began speaking at nine that night.

New and better stem cell lines were generated with funds from nonfederal sources, principally the Howard Hughes Medical Institute, private philanthropies, laboratories abroad and industry. But these lines could not be studied with NIH grants. Legislation to broaden the repeligible cell lines twice was passed by the U.S. Congress and vetoed by President Bush.