German Friedrich Soennecken invented ring binders in 1886 in Bonn, Germany. He also registered a patent on November 14, 1886 for his Papierlocher für Sammelmappen (hole punch). Another design for ring binders was invented in 1889 by Andreas Tengwall in Helsingborg, Sweden and patented in 1890 under the name 'Trio binder', named after a business consortium of Tengwall and two associates. Tengwall's design uses four rings, two coming from each side in a forking fashion. The hole placement of Tengwall's Trio binder is still used as a de-facto standard for hole punching in Sweden under the name triohålning. A few years later 3 ring binders became the standard in the US, and the "D" ring binders didn't come on the market there until the 1940s or 1950's.