IF there’s one word worse than the c-word in City ­circles, it’s the m-word: manipulation. If you don’t believe me, take the experience of an acquaintance of mine the other day.

In these phone-taped, CCTV-recorded times, your choice of language could pass the test of both God and your grandmother and still bag you a P45 in record time. This instance involves those notoriously anti-competitive and abusive hedge funds, which have had a few setbacks of late.

Indeed, if you thought the large investment banks were taking big hits in these turbulent times, they seem positively chirpy compared to their cowboy counterparts. Skittish investors pulled out £20bn from hedgies in the third quarter this year, the largest amount in any quarter since 1993. As a result, one after another, funds have disappeared into the black hole created by the financial crisis. Among the lucky few remaining, the song of survival seems to be this: desperate times call for desperate (read manipulative) measures.

My acquaintance at a rival investment bank caught on to this naughtiness one day when he saw false bids being placed lower and lower on one particular European stock in which he knew his hedge fund client was short. (For the uninitiated, false bids are fake offers set lower than the market price aimed at making the stock look cheaper than it is in a bid to drive down the price.)

Of course, all of us bankers hear rumours of wrongdoings. But we don’t worry about it, we don’t talk about it, and we definitely don’t write about it on our company’s Bloomberg terminal. But he did. “You manipulative c**t,” wrote the idiot in an email to his client – a fatal error.

When his bank was informed that it may be investigated by the FSA for enabling this manipulation, it panicked, ­sifting through records of every phone call, email and data terminal message on the floor. They found nothing incriminating – except his message. He was fired on the spot.

In the City, words belong to their creator, not his employer. Had my acquaintance just said “You c**t”, he might have been required to brush up on his manners, but he would still have a job.