Source: US Global Legal Monitor
The following is a guest post by Tanja Krüger, a foreign law intern working with Foreign Law Specialist Jenny Gesley at the Global Legal Research Directorate of the Law Library of Congress.
While enjoying my morning coffee today, I found myself thinking back to a few vacations where coffee was served the traditional way – with grounds settling at the bottom of the cup. Though it added to the local experience, it also reminded me how much I appreciate the convenience of a coffee filter. This thought led me to explore the history of the coffee filter and the invention that changed how millions enjoy their daily coffee. As the coffee filter patent marks its 118th anniversary on July 8, 2026, it is a fitting time to look back at one of coffee culture’s most influential innovations and its inventor Melitta Bentz.
Born in 1873, Melitta Bentz lived in Dresden, Germany, with her husband and three children. While hosting a coffee gathering for friends, she became frustrated by the grounds in her cup and the bitter aftertaste they left behind. Determined to improve the brewing process, she began searching for a way to filter the grounds from the coffee.
Before the coffee filter was invented, coffee was commonly brewed by mixing finely ground coffee directly with hot water and allowing the grounds to settle at the bottom of the pot or cup. This method is still known today as Turkish coffee or Mokka coffee, and remains popular across Turkey, Greece, southeastern Europe, and the Middle East. The tradition and culture surrounding Turkish coffee are recognized by UNESCO as part of its Intangible Cultural Heritage list.
At the time of Melitta Bentz, existing coffee filters were either too fine or had holes that were too large, allowing grounds to pass through into the coffee. Seeking a better solution, Melitta Bentz took blotting paper from her son’s exercise book. She then punched holes in a brass cup, lined it with the paper, and poured the coffee through it. This simple method effectively filtered out the grounds while preserving the coffee’s flavor.
Recognizing the value of her invention, Melitta Bentz filed a patent application for her coffee filter with the German Imperial Patent Office in June 1908. She described her invention as: “A coffee filter with a bottom that curves downward and has a drainage hole, and a loose-fitting filter screen.”
The patent was granted by the Imperial Patent Office and published in the Patent Gazette (Patentblatt) on July 8, 1908, on page 1145. Seizing the opportunity, Melitta Bentz launched her business with her husband, Hugo Bentz, on December 15, 1908, to market the Melitta coffee filter. The company began with just 50 filters and used an unusual marketing approach for the time: her husband visited local shops to show how it worked and demonstrated the filter in storefronts.
Over time, Melitta Bentz built a successful business and continuously refined the coffee filter. In 1937, she patented the now-familiar cone-shaped paper filter designed for use with a porcelain dripper with the Patent Office of the German Reich (Reichspatentamt).
During the First World War, imports of goods declined, making both coffee and filter paper scarce. As a result, coffee substitutes such as “Muckefuck” became common in Germany. Despite these challenges, Melitta Bentz managed to keep her company afloat and guide it through this difficult period.
During the Second World War, the Melitta company was led in part by Melitta Bentz’s son Horst Bentz, who also joined the Protection Squadrons (Schutzstaffel – SS). The company was involved in production for the German war economy, manufacturing items such as cookware for the military as well as materials like ammunition belts and grenade casings.
Melitta Bentz died in 1950, but her invention continues to shape modern coffee culture. The company she founded remains active today.
Additional Law Library of Congress Resources
- Kim Marie Eberhardt, Taxation of Prepared Meals and Drinks in Germany and the United States, In Custodia Legis (2025)
- Maximilian Haedicke, Patentrecht (7th ed. 2025)
- Patentgesetz mit Europäischem Patentübereinkommen : Kommentar auf der Grundlage der deutschen und europäischen Rechtsprechung (Rainer Moufang & Cornelia Rudloff-Schäffer, eds., 12th ed. 2025)
- Bailey DeSimone, Stumpy’s Legacy: Laws on Plant Patents and Propagation, In Custodia Legis (2024)
- Zeynep Timocin Cantekin, FALQs: The Unified Patent Court and Unitary Patents in Europe, In Custodia Legis (2020)
- Jacquelyn Deppe, Celebrating International Coffee Day: For the Love of Coffee, In Custodia Legis (2020)
- Research Guides: Women Inventors and Patent Holders – Women in Science and Technology: A Resource Guide
- Global Legal Monitor: Intellectual Property
- Global Legal Monitor: Germany
- Catalog search for “patents”
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