22 of the 27 EU-member countries have signed the agreement intended to protect intellectual property rights, but Germany said on Friday that it would delay its signature until further notice.
"The European Parliament has a responsibility to engage with and evaluate the facts regarding ACTA," German Federal Judiciary Minister Sabine Leutheusser-Schnarrenberger said.
"But Germany has no need to enact such legislation. We have lifted any censors on websites, and see no reason to block internet connections due to copyright infringements."
Criticism levied against ACTA has echoed that from SOPA and PIPA opponents in the US, citing the dangers of censorship, lack of transparency and the limitations they stand to impose on free speech and democracy.
Munich saw the largest protester turnout in the country with 16,000 people showing up to demonstrate against adoption of the multilateral agreement. Officials counted around 6,000 protestors in Berlin, with Dortmund and Cologne totaling about 4,500.
"It was a successful, peaceful and loud demonstration," Munich organizer Roland Jungnickel told the daily Sueddeutsche Zeitung. "The high number of participants shows that the issue is an important one."
Eleven countries and unions hashed out the details of ACTA during 2010, including Australia, Canada, the EU, Japan, South Korea, Mexico, Morocco, New Zealand, Singapore, Switzerland and the U.S., the Sueddeutsche reported. The EU signed in the agreement last month, with the European Parliament and the German Federal Parliament still due to adopt the measures.
Three German parties have expressed opposition to ACTA including the Greens, the socialist Left party and the Pirates, with members of the Free Democratic Party also expressing opposition, according to TheLocal.de.
Michael Kretschmer, internet policy spokesman for Chancellor Angela Merkel's Christian Democratic Union (CDU) has also called for transparency in negotiations, saying on Friday in Berlin that it does not inspire trust among the population, “if these contracts come about like secret agreements,” according to TheLocal.de.