Edison was not the first to invent the light bulb, but his 1879 patent described the most commercially viable design using a carbon filament. While others had experimented with light bulbs, Edison's team succeeded in developing a carbonized bamboo filament that could last over 1200 hours. Edison aggressively enforced his patents, purchasing competitors' patents and suing infringers like Westinghouse. Although Westinghouse argued Edison was not the true inventor, the court found Edison's patent covered the carbon filament method and prevented others from developing competing bulbs without infringing. Edison's business success and public relations strategies also made competing against him very difficult.

1. Let There Be Light… And Litigation
If there is one invention that not only changed the way the people lived at
the time it was made, but has gone on to be used by almost the entire
world ever since, then that invention is the electric light bulb. The history of
the light bulb’s development and patent ownership is an interesting one,
involving the man who has been described as America’s greatest inventor,
as well as one of its most controversial: Thomas Edison.

2. Edison was, of course, not the first person to invent a kind of electric light
bulb. His breakthrough US patent application, which described what
became the most commercially viable arrangement, was filed in 1879 and
the patent was granted in 1880. However, as far back as 1800, Alessandra
Volta had developed a method for conducting electricity using, amongst
other materials, copper wire.
In 1840, British scientist Warren de la Rue developed a light bulb with a
platinum filament and, although this bulb was highly efficient, the high cost of
platinum prevented this bulb from succeeding commercially. Many others,
including Henry Woodward, Mathew Evans, Humphry Davy, James
Bowman Lindsay, Moses Farmer, William Sawyer, Joseph Swan, and
Heinrich Göbel, designed incandescent lamps taking various forms, none of
which proved to be particularly successful from a commercial point of view.
Edison employed a team of scientists at his Menlo Park, New Jersey
laboratory, to overcome the problem associated with these prior designs –
which was down to the filament being used to conduct electricity. Edison
realised that what was needed was a filament with a high electrical
resistance, which could use a small amount of current to achieve long-
lasting light. Edison’s team experimented with various filament materials,
realising that carbon-based filament performed best and refining this to
develop a carbonised bamboo filament which could burn for over 1200
hours before failing.

3. Edison knew how to use the patent system to his advantage – in the case of
the light bulb, not only did he purchase many of his competitor’s patents, but
he filed his breakthrough “Electric Lamp” patent applicationcovering various
ways to build a light bulb, listing a variety of carbonised materials which
could be used as the filament, including the bamboo which was eventually
settled on. Once Edison had hit on the combination that was the most
commercially viable, he wasn’t shy to pursue infringers and protect “his”
invention.

4. Once Edison has secured his Electric Lamp patent, litigation inevitably
followed. The most prominent case involved George Westinghouse and
was, no doubt, linked to Edison and Westinghouse’s wider battle over the
provision of electrical power to the masses.
While Westinghouse convincingly argued that Edison was not first to invent
the light bulb, the court found that he was first to successfully draft a patent
which covered the specific method of utilising a carbon filament, and the
patent was drafted in such a way that not only did it cover the later
development of a carbonised bamboo filament, but it also meant that there
was almost no route around the patent to allow someone to develop a
commercially successful light bulb that did not infringe Edison’s patent.

5. Edison worked with a team of 14 or so engineers, machinists, and physicists—collectively
known as ‘muckers.
Another example of Edison’s patent-savvy outlook is that, whilst other
researchers at Edison’s laboratory undoubtedly contributed to the
development of the light bulb, it was never able to be shown that anyone
else had made a specific contribution.
Whilst Edison’s patent know-how undoubtedly furthered his position, he had
also built a strong business by this time. This fact, coupled with his
advanced PR strategies, meant that anyone looking to enter into Edison’s
field of business (even someone with the financial backing of

6. Westinghouse) could not realistically hope to do so without having to battle
against Edison – a battle that most competitors were not able to win.
About Dawn Ellmore Employment
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