It is also a history of class, of geography, of education, and of the specific social networks through which commercial relationships are built and maintained.

But race and gender are the most significant factors in Mary Kenner’s specific story, and they deserve to be named clearly and precisely.

She was overlooked because she was Black and because she was a woman, in an era when being Black and being a woman were active disadvantages in the commercial world where inventions became products.

The structural forces that produced her obscurity were racial and gendered.

This is not a comfortable truth for a country that celebrates the democratic openness of its patent system and the meritocratic character of its economic life.