Countries have been negotiating international copyright treaties for more than a century, but the passage of two treaties in the 1990s represented a turning point in international copyright law.

The Trade-Related Aspects of Intellectual Property Rights (TRIPS) agreement, signed in 1994, made protection of copyrights a requirement of membership in the World Trade Organization. Countries that failed to meet international copyright standards could face trade sanctions. The 1996 World Intellectual Property Organization Copyright Treaty further ratcheted up the minimum requirements for copyright protection—requiring, for example, that signing countries regulate the circumvention of digital rights management schemes.

WIPO's relatively open structure meant that major copyright holders didn't get everything they wanted in the 1996 treaty [...] the United States was unable to get the strong anti-circumvention language it preferred into the WIPO treaty [...]

So [...] the US has increasingly engaged in forum-shopping, bypassing WIPO and pushing for stronger copyright protection in a wide variety of other venues. [...] The negotiations over the Anti-Counterfeiting Trade Agreement were part of this trend. In contrast to the relatively open WIPO process, ACTA was negotiated in secret by a relatively small number of mostly wealthy countries.