The lawsuit's power of attorney letters filled some 70 boxes and were brought by truck on Wednesday to Germany's top court located in Karlsruhe, the Constitutional Court.
The proposed Comprehensive Economic and Trade Agreement (CETA) would eliminate about 98 percent of the tariffs between the EU and Canada, but it has been condemned by opponents who say it will too greatly expand the power of corporations and may lower certain EU standards for things like food safety and production, in favour of businesses.
“[CETA] is a danger to our democratic, social and environmental standards, as well as to the general interests of the public,” said German anti-CETA initiative Campact in a statement on Wednesday.
“We must make sure that the German government refuses to sign on.”
The head of advocacy group Global Justice Now, Nick Dearden, wrote in an opinion piece for the Guardian earlier this year that CETA will create “a new legal system”.
“Should the British government make a decision, say, to outlaw dangerous chemicals, improve food safety or put cigarettes in plain packaging, a Canadian company can sue the British government for ‘unfairness',” Dearden wrote. “And by unfairness this simply means they can't make as much profit as they expected.”
Wednesday's suit is the fifth constitutional complaint filed against CETA in Germany.
Top German officials on the other hand have praised the proposed deal. Vice-Chancellor Sigmar Gabriel said on Sunday that the agreement was a “big step forward” and that he would fight for it to be passed.
Negotiations for CETA were formally concluded in 2014, but the deal still requires the approval of the 28 EU member states as well as the European Parliament.