This World IP Day we, at the Business & IP Centre, are shining the light on women inventors to celebrate this year's theme of Women and IP: Accelerating Innovation and Creativity. We heard from the curator from our historical patent collection, Steven Campion, on just some of his favourite inventions patented by women in 2021 for International Women's Day. Now he's added a couple more to the list, who despite not receiving a patent for their remarkable work, have left an indelible mark in the field of innovation and paved the way for future generations of female inventors.
'I decided to add them as they are rightfully considered to be pioneers in their respective fields, which is all the more remarkable considering they worked during a time when it really was a man’s world. Their inclusion also serves as a nice reminder that not all innovations or breakthroughs are patentable, and not all innovators seek to protect their work with a patent.
Although women have always found solutions to the problems around them, social and historical factors mean little of this was recorded. Women inventors would have had fewer resources and faced discriminatory barriers at every step of their journey – often having their contributions downplayed or overlooked entirely.
Therefore just 62 out of the 14,359 patents granted in England between 1617 and 1852 were awarded to women. In fact before 1965, the proportion of women in the UK patent system was generally between 2% and 3%. The proportion has since risen at an accelerating pace, having reached 6.8% in 1998, and then almost doubling to reach 12.7% in 2017. As the number of women working within the STEM sector increases, we can hopefully look forward to this number rising further.
Before we begin, a quick caveat. Earlier patents may exist for some of the inventions given in this list but the following women are widely considered the inventor of their ‘thing’ because it worked (earlier versions didn't in some cases), or it was popular, or it is recognisable to the form as it exists today, and so on.
Marie Curie

Trying to do justice to the life and work of Marie Curie (née Sklodowska) in just a few hundred words is almost impossible. She is one of the most famous women of the 20th century, being the first woman to win a Nobel Prize, the first person to win a Nobel Prize twice, and the only person to win a Nobel Prize in two scientific fields (Physics and Chemistry).
Curie and her husband and research partner, Pierre, discovered polonium and radium, developed a technique for isolating radium in its pure form, and coined the term 'radioactivity'. Notably, Curie chose not to patent radium, or any of its medical applications, to ensure it could reach its full potential in benefiting the world.
During World War One, Curie also developed mobile X-ray vans known as petites Curies, which saved countless lives on the battlefield. She and her daughter, Irène, trained around 150 women to become radiology assistants for the vans.
Marie Curie is also the name of the UK’s leading end of life charity (and owners of some great charity shops – I’d recommend the one in Highbury). But how did this come about?
In 1930, Curie gave a North London hospital permission to use her name. Staffed entirely by women, the pioneering Marie Curie Hospital treated female cancer patients using radiology. The hospital was destroyed during an air raid in 1944, but the committee overseeing the rebuild decided to separate it from the newly formed NHS, creating instead (with permission from Curie’s daughter Eve) the charity now known as Marie Curie.
Marie Curie has inspired countless women into STEM careers, and will surely continue to do so for generations to come.
Grace Hopper

Grace Hopper (née Murray) was teaching mathematics when the Japanese attack on Pearl Harbour thrust America into the Second World War. Wanting to do her bit, Hopper joined the newly formed women's branch of the United States Naval Reserve – despite being told she was too old and small.
Hopper was assigned to the Bureau of Ships Computation Project at Harvard University, where she was one of the first programmers of one of the world’s first electromechanical computers – the IBM Automatic Sequence Controlled Calculator, more commonly known as the Mark I. The manual she wrote for the machine is considered to be the world’s first computer user manual.
Opinion is split on this, but Hopper may have been the first person to describe a computer problem as a ‘bug’, and the fixing of said problem as ‘debugging’. These terms were used very literally by Hopper, when the problem she encountered was discovered to have been caused by a dead moth inside the machine.
After the war, she joined the Eckert–Mauchly Computer Corporation where she helped to develop the UNIVAC I – the first commercial electronic computer. Here she developed the world’s first compiler, which translated mathematical code into code that could be understood by a computer. The first step in allowing data processors to write programs in English, and the beginning of COBOL, one of the major languages used today in data processing.
This is just a small taste of Grace Hopper’s many achievements. Today she is rightfully remembered as one of the most important figures in the history of computing, and a true STEM pioneer.
Mary Anderson – windscreen wiper

A copy of the U.S. patent can be seen here.
Mary Anderson visited New York City in the winter of 1903. This was the year before the subway opened and the streetcar was a popular way to get around town. During her trip it snowed heavily, forcing the streetcar drivers to frequently stop to clear the snow and ice from their windscreens. When this became unmanageable, they would instead drive with their head sticking out of an open window.
Delays and open windows of course meant discomfort for the passengers, especially someone like Anderson who was not used to the chill of a New York winter.
Knowing there had to be a solution, Anderson began work as soon as she returned to Alabama. Her finished prototype was a radially swinging rubber blade which would wipe the windscreen clear of obstruction. Fairly similar to the modern-day windscreen wiper, except Anderson’s invention was manually operated by a handle inside by the driver (in 1917 another female inventor, Charlotte Bridgwood, was granted a patent for the first electrically powered windscreen wiper).
On the 10th November 1903, U.S. patent no. 743,801 was granted to Anderson for her ‘window-cleaning device’. Unfortunately not many people saw the worth in her invention, saying it would be a dangerous distraction to the driver. Cars were also not particularly common and Ford’s Model T was still 5 years away. Anderson therefore made no money from her patent and it eventually lapsed.
As driving became more commonplace, the windscreen wiper was eventually adapted for automotive use, today being an important safety device that is a legal requirement in most countries.
Mary Walton – pollution reducing devices

A copy of U.S. patent no. 221,880 can be seen here; the historic IP collection at the library contains a paper copy of the GB version of the patent (GB 3,512 of 1879).
A copy of U.S. patent no. 237,422 can be seen here.
Elevated trains were installed throughout the larger U.S. cities in the second half of the 19th century, unfortunately bringing a large amount of air and noise pollution for those living nearby. Mary Walton, who lived beside the tracks in Brooklyn, worked to solve both problems, earning herself a place in history as a STEM female pioneer.
In 1879 she was granted U.S. patent no. 221,880 for ‘Improvement in locomotive and other chimneys’. Her invention reduced air pollution by diverting chimney smoke through water tanks. This process dissolved and trapped the pollutants in the water, which would later be flushed into the sewer system.
Next, she realised that wooden elements of the track were amplifying the noise of the trains. Using a model railway she built in her basement, she came up with a working solution – encasing specific sections of the track in weatherproof wooden boxes filled with sand. This successfully absorbed the majority of the vibrations; greatly reducing the noise levels. Before Anderson, many noted engineers and inventors tried and failed to find a solution, including Thomas Edison.
After successful trials, Walton was granted U.S. patent no. 237,422 in 1881. She sold the patent rights to New York City’s Metropolitan Railroad, and before long the system was in place throughout America.
Josephine Cochrane - first commercially successful dishwashing machine

A copy of the U.S. patent can be seen here; the historic IP collection at the library contains a paper copy of the GB version of the patent (GB 9,895 of 1887).
Josephine Cochrane, a 19th century socialite, often hosted grand dinner parties at her mansion in Illinois. She was fortunate enough to have servants to wash up afterwards, but Cochrane was unhappy to discover the occasional chip in her heirloom china. She therefore decided to wash the dishes herself, though soon became bored of the task.
So bored in fact, that Cochrane designed a machine to take over. Her machine used water pressure to clean dishes held in place by wire racks – a system recognisable to anyone with a modern dishwasher.
The first few male engineers she hired predictably insisted on changing her design. They were convinced they knew better than an untrained woman, but their changes never worked. Eventually her design was built and U.S. patent no. 335,139 was granted for her ‘Dish washing machine’ in 1886.
At the time the machine was too expensive for most homeowners and required more hot water than the typical home could generate. But after winning a top prize at the 1893 World’s Fair in Chicago, orders poured in from hotels, restaurants, and hospitals.
In 1898 Cochrane started her own company which she managed until her death in 1913. In 1926 the company was acquired by Hobart, which went on to produce the first successful home dishwashers under the KitchenAid brand in the 1940s.
Today half of all UK households have a dishwasher thanks to the pioneering work of Josephine Cochrane – presumably the other half wishes they had room for one.
Margaret Knight - machine for making flat-bottomed paper bags

A copy of the U.S. patent can be seen here.
In 1867 Margaret Knight started work at a paper bag factory. At the time, mass produced paper bags had envelope style bottoms, which were both weak and narrow. Flat-bottomed bags were stronger and made packing easier, but there was no machine that could make these. Instead a production line of 30 women were employed to cut, fold, and glue these together. Flat-bottomed bags were therefore expensive and uncommon.
Knight was an inventor at heart. At the age of just 12 she had invented a loom safety device that was used extensively by the cotton industry (but unfortunately not patented). She therefore soon developed a machine that could manufacture flat-bottomed bags from start to finish – something male inventors had been trying and failing to do for years. In 1871 Knight applied for a patent, but was rejected as a similar machine was recently patented by Charles Annan.
Before her application, Knight had visited several machine shops in order to create an iron prototype. At one of these, Annan saw the plans and decided to steal the invention. Knight filed a patent interference lawsuit, with a mass of documentation and witness testimony on her side. Annan could only really state that no woman could design such a machine. Knight of course won, and U.S. patent no. 116,842 was granted for her ‘Improvement in paper-bag machines’ in 1871.
Knight would continue to innovate, being awarded many more patents over the course of her lifetime.
Melitta Bentz – the coffee filter

The industrial property right was granted with registration on page 1145 of the 8th July 1908 edition of the patent gazette of the Imperial Patent Office in Berlin – see image.
Like many of us, Melitta Bentz enjoyed starting her morning with a cup of coffee. What she didn’t enjoy was the bitter tasting coffee grounds still left floating in her cup.
At the time, coffee was usually brewed by pouring ground coffee into hot water and then waiting for the grounds to settle to the bottom. Sieves and cloth bags would help, but they either let too many coffee grounds through, or would be so narrow that the coffee would be cold by the time it was filtered.
One day Bentz had a flash of inspiration. She drilled holes into the bottom of a brass pot, which she then sat on top of a cup. Next, she placed a piece of blotting paper from her son’s school exercise book into the bottom of the pot, adding freshly ground coffee on top. Bentz then poured hot water into the pot and watched as clean, filtered coffee dripped into the cup below – she had invented pour-over coffee and the coffee filter.
In 1908 Bentz was granted utility model 343,556 for her ‘Coffee filter with a domed underside, recessed bottom and inclined flow holes’ from the patent office in Berlin. The same year she founded the company ‘Melitta’ and began to sell her pot and filter paper. In the 1930s Melitta would go on to create the cone shaped filter and today, the still family owned business, produces over 50 million filters a day.
Despite the ease of modern coffee brewing methods, pour over coffee has remained popular amongst coffee lovers, who appreciate the high level of control it provides.
Elizabeth Magie – the landlord’s game

A copy of the U.S. patent can be seen here.
For the longest time it was an accepted fact that Monopoly was invented by Charles Darrow in 1933. It wasn’t until the 1970s that a decade long trademark infringement lawsuit revealed the actual truth – Monopoly was heavily based on another board game patented decades earlier by a progressive woman called Elizabeth Magie.
Magie was granted U.S. patent no. 748,626 in 1904 for her board game ‘The Landlord's Game’. It was designed to illustrate the anti-monopolist theories of 19th century economist Henry George, and as such it came with two rule sets – one monopolist, the other anti-monopolist. The idea being players would see the latter was the morally correct choice.
Failing to find a publisher, Magie self-published the game in 1906. It sold poorly, but a local economics professor picked up a copy and played it with his students. At the time it was not uncommon to create handmade versions of published games, and that’s exactly what several of these students did, and it’s exactly what several friends of these students did, and so on.
As the homemade versions spread, the game would change a little here and there. New house rules would be added and the street names would be updated to reflect local towns. Ironically, people thought it was more fun to own land, charge rent, and bankrupt friends and family, and so the anti-monopolist rules were left permanently to one-side.
Fast forward to 1932, and Charles Darrow is introduced to a home-made version of the game. He immediately creates his own copy and starts to sell it under the name ‘Monopoly’. It does well and he sells the board game rights, becoming the first millionaire game designer in history. By contrast, Magie is said to have earned only $500 from her board game.
Hedy Lamarr – frequency-hopping

A copy of the U.S. patent can be seen here.
Hedy Lamarr was a Hollywood icon who was promoted as ‘the most beautiful woman in film’. She was so startlingly beautiful in fact, that her brilliant mind was largely overlooked her entire life. It wasn’t until her later years, and sadly really only after her death that the world would learn of her part in the development of the wireless technologies we take for granted today.
It was World War Two, and Lamarr had heard that German U-boats were easily jamming the signals that guided the radio-controlled Allied torpedoes. She hit on a brilliant solution – if the signal hopped from frequency to frequency rapidly, then it would be near impossible to detect and jam.
She asked a composer called George Antheil to help realise her invention, and together they created a system that used paper piano rolls, perforated with a complex and random pattern, to make a signal hop rapidly between 88 frequencies – the same number of keys on a piano.
U.S. patent no. 2,292,387 was granted for their ‘Secret communication system’ in 1942, however the Navy declined taking their idea forward. It is thought the invention was not taken seriously as it was created by an actor who was world famous for her beauty.
However during the Cuban Missile Crisis in 1962, about three years after the patent had expired, the technology was adapted and in use. Fast forward many more years and frequency-hopping would be foundational to modern wireless technologies, such as GPS, Bluetooth, and secure Wi-Fi.'
For more on intellectual property and female founders, you can visit at the Business & IP Centre resources at bl.uk/bipc.