The Trans-Pacific Partnership is an expansion of what's called the Trans-Pacific Strategic Economic Partnership— conceived in 2003 by Singapore, New Zealand, and Chile as a path to trade liberalization in the Asia-Pacific region.
The U.S. started talks in 2008 under the Bush administration to expand the group. Those efforts were intensified with the Obama White House in 2010.
Now, 11 other nations are negotiating to be in the bigger TPP. They include Japan, Australia, Peru, Malaysia, Vietnam, New Zealand, Chile, Singapore, Canada, Mexico, and Brunei. South Korea, invited into the talks, has taken a wait-and-see attitude for now.
"This is extremely complicated and there are many angles to it," said Andreas Hauskrecht, an international economics professor at Indiana University.
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"We have trade agreements with several of the countries involved, but this would be bigger and far more reaching," Hauskrecht said.
Some information about the 29 known chapters or provisions has leaked—WikiLeaks being one source—but most information about the proposed pact has trickled out through the Office of the United States Trade Representative.
Even that agency says secrecy is part of the deal: "To create the conditions necessary to successfully reach agreement in complex trade and investment negotiations, governments routinely keep their proposals and communications with each other confidential," says a statement on the USTR website.
What's known so far is that only five of the 29 sweeping provisions in the pact cover such trade areas as tariffs, government subsidies and quotas.
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The other policies being discussed would set new rules for food safety and prices for medicine, create tighter provisions for Internet freedom, provide stricter copyright laws, as well as extend the length of generic patents for drugs. All countries in the TPP would have to follow the rules set out by the agreement instead of their own country's regulations.
"This is why we are fighting this," said Lori Wallach, director of Global Trade Watch for Public Citizen, a non-profit consumer group. "We supported almost all the major trade agreements in the past, but this goes beyond free trade. It's become a Trojan Horse for all these other provisions of one-size-fits-all."