Attempts to extend patent life beyond the 17 or 20 years established by law are controversial.

The 12 years invested in researching the drug in Finland have eroded much of the drug's patent life.

Since 1996, there have been at least a half dozen attempts to extend Claritin's patent life even more.

This was partially due to Parke-Davis's reluctance to invest in a drug nearing the end of its patent life.

The remaining drugs seeking extra patent life also have powerful parents.

Part of that calculus might depend on the patent lives of the drugs in question.

American patent law was changed in 1995 to prevent such extensions of patent life.

She added that the new world trade agreement "provided for a 20-year patent life, and what this decision does is uphold that patent protection."

Finally, I wish to clarify the issue of the patent life of medicines, as some colleagues have expressed concern.

It came on the heels of a failed attempt by the pharmaceutical industry to persuade Congress to extend the patent life of brand-name drugs.