Who is the inventor of light speed?

Answer 1

The speed of light was invented by whoever or whatever invented the universe, sun, moon, and earth.

Since its invention happened a long time before there were people around to see it happen and wonder about it, all that remained for us to do when we came along was to measure it.

Answer 2

There is no inventor of the speed of light. The speed of light is how fast light travels across the universe, which is 299,792,458 meters per second, or 186,282 miles per second.

EDIT:

I would say God, but history has been more kind to give credence to Albert Einstein for his discoveries in 1905 where he showed that the speed of light in a vacuum was independent of the source. This postulation by Einstein was the basis for what we now know as the Theory of Relativity shown by the equation:

e=mc2 where "c" is the speed of light at 3.00 x 108 m/s