He said drug patents were not designed to create a situation "where we can be just exploited forever by the wealthy and the powerful."
Companies transfer drug patents to their own foreign subsidiaries, he said.
In the last 10 years, more than 8,900 applications for drug patents have been filed, and the process to clear them is sure to be slow.
When new drugs are first made they have drug patents.
Most drug patents are protected for 20 years.
The administration predicted that the generic drug bill would increase litigation over drug patents.
In the US, drug patents give 20 years of protection.
Thai law allows the health minister to declare an emergency and seize a drug patent.
They fought about drug patents, farm subsidies, bananas and tuna.
New opportunities in that battle are on the way as more major drug patents expire.