Laws protecting intellectual property rights encourage private sector seed research and development. This report examines the Plant-Variety Protection Act (the PVPA) of 1970 as well as the Plant Patent Act (PPA) of 1930 and other forms of research protection, such as utility patents (UP's) and trade secrecy. The report explores the relative profitability to farmers of using purchased seed rather than bin run seed (the previous year's harvest), since the use of purchased seed encourages private seed research and development. To compare profits, winter wheat yields are regressed against the source of seed and other variable inputs for three sections of the United States in 1986/87 and 1987/88. The results show that, on average, farmers who use bin run seed could increase yields by using purchased seed. Also, profits would probably increase both for farmers who begin purchasing seed and for the private seed research sector.