This chemical was known since the early 1800s through its salts and via the products of reactions in which it was proposed to exist,[3] but the acid itself was not detected until 1966.

It wasn't until the 1966 isolation and analysis of a pure sample of fulminic acid that this structural idea was conclusively disproven.

[3] The chemical that actually has that structure, isofulminic acid (a tautomer of the actual fulminic acid structure) was eventually detected in 1988.

[4] A convenient synthesis involves flash pyrolysis of certain oximes.

In contrast to earlier syntheses, this method avoids the use of highly explosive metal fulminates.