History
PatentGuessr
Guess the invention from a real patent drawing. One mystery patent a day from the US archives, six guesses, with clues straight from the file, filing date, scale, class, and the redacted claim.
Each date on DLE Directory highlights one daily puzzle worth trying. For Saturday, December 26, 2026, we are introducing PatentGuessr — a history DLE that usually takes 3–10 min.
Guess the invention from a real patent drawing. One mystery patent a day from the US archives, six guesses, with clues straight from the file, filing date, scale, class, and the redacted claim.
