Fact Check-Lewis Latimer invented a longer lasting filament for lightbulbs, not the lightbulb itself

A widely shared post on social media says Thomas Edison did not invent the lightbulb but stole it from a Black man called Lewis Latimer. Latimer made a major contribution to the development of electric lighting by inventing a longer-lasting filament. But he did not invent the lightbulb. Thomas Edison is regularly identified as the inventor, though that claim is itself often challenged.

The post ( here ) reads: “This is your daily reminder that Thomas Edison did NOT invent the lightbulb, he stole it from a black man named Lewis Latimer.”

U.S. President Joe Biden echoed the message at a community meeting in Kenosha, Wisconsin on the campaign trail on Sept. 3, 2020, when he said: “A Black man invented the lightbulb not a white guy named Edison,” as seen here .

Politifact, Snopes and CNN fact-checked Biden’s claim at the time and found it to be partly false (here , here , here).


Lewis Latimer (1848-1928) was an African-American inventor, electrical pioneer and patent expert ( , here , here ).

After 11 years working as a patent lawyer for inventors such as Alexander Graham Bell (working on the telephone) and Hiram Maxim (in his United States Electric Lighting Company), Latimer started to work with Edison General Electric in the late 1880s as a patent expert (see from the five minute-mark in the video ).

In 1890 he published a book on the Edison system and the development of the incandescent light by Edison, called “Incandescent Electric Lighting: A Practical Description of the Edison System” ( here ).

The website for the museum based in his old house says Latimer “invented the carbon filament, a significant improvement in the production of the incandescent light bulb” ( ).

The website for Lemelson-MIT, which awards prizes to inventors in the United States, goes into more detail, saying: “Edison’s light bulb used a carbonized bamboo filament, which unfortunately burnt out rather quickly. Latimer created a way to make the carbon filament more durable by encasing it in cardboard.” (here)

Latimer filed a patent for the process for efficiently manufacturing the carbon filament in September 1881. The patent can be seen here here . Edison’s patent for his lightbulb, seen here , was granted around one and a half years earlier in January 1880 ( here ).

Latimer also supervised the installation of public electric lights throughout New York, Philadelphia, Montreal and London (see here and here ). His other patented inventions included the first toilet for railroad cars and a forerunner of the air conditioner ( here ).


Although Edison is commonly credited with inventing the lightbulb, though that is still regularly challenged, as seen here , here , here and here .

Edison was not the first to create an alternative to gaslight and his incandescent electric light built on the work of others who had used electricity to make light before him, as explained in the Encyclopaedia Britannica here and on the U.S. Department of Energy website here .

Both Edison and Sir Joseph Swan, an English physicist, applied for patents for their carbon-filament incandescent lamps around 1880. The ensuing litigation was resolved in 1883 when Swan and Edison formed a joint company (here , here).

However, Edison’s incandescent electric light was practical for home use and lasted longer than earlier models thanks to the filament, as explained by the Thomas Edison Center ( here ), The National Park Service Edison biography ( here ) and Time Magazine ( here ).


Partly false. Latimer did not invent the lightbulb but did provide key improvements to the invention.

This article was produced by the Reuters Fact Check team. Read more about our work to fact-check social media posts here .