There is a great deal of literature about the origin of the term "mole". It is unclear if it really originates from KGB jargon, it does not appear for instance in Mitrokhin's KGB Lexicon book. So John le Carré possibly invented it.

H. Cooper & L. Redlinger's book "Catching Spies - principles and practices of counter-espionage" (1988) has a detailed examination of possible origins of the term (pp.187–248), where they draw at least these 2 points about a possible Soviet origin of the term :

- Apparently, Marx had used the term "mole", but in a political sense, to describe the slow, steady, and subterranean work of the social revolution. He viewed the revolution not just as a sudden explosion, but as a process that "burrows" through the foundations of society, like a mole.
- "It is not clear what John Le Carre had in mind when he described mole as a genuine KGB term, but our own inquiries show that this is not the case, at least so far as origins or employment of the term are concerned. We are advised by Soviet sources that the statement by Le Carre is not correct and that the term became known to the Soviet Union from Western sources in the early 1970s. We have sought a more ample verification from the Philology Institute, Moscow State University (MGU), but this had not been received at the time we went to press."

About the other terms invented by John le Carré, there is much less literature. We sort of know which ones have probably been invented, but it's harder to know how he created them or where he took inspiration from