Dennis Ritchie’s Unsubmitted Dissertation Still Raises Questions

• 

  Dennis Ritchie wrote a doctoral dissertation but never submitted it to Harvard University.

• 

  The reason he did not submit it remains unknown.

• 

  A version of the dissertation is held by the Computer History Museum.

• 

  Researchers later investigated how Ritchie produced the work using the technical tools available in 1968.

• 

  Ritchie, a major contributor to Unix and the C programming language, was found dead at home on 12 October 2011.

Who

Dennis Ritchie wrote the dissertation. Brian W. Kernighan, Bill Ritchie and David F. Brailsford later investigated how it was produced.

What

Ritchie wrote a dissertation on subrecursive function hierarchies but did not submit it to Harvard.

When

The dissertation was about a 1968 subject; the sources do not state when he wrote or completed it.

Where

Harvard University was where he did not submit it. A copy is held by the Computer History Museum.

Why

The reason he never officially submitted it is unknown. An oral account says he objected to paying for a bound copy, but this is not confirmed.

This story does not have two clearly opposing sides.