The recruits will boost the watchdog's fight against insider dealing, with more than 80 staff dedicated to investigating so-called wholesale cases that involve financial institutions and their employees.
Although the lawyers' identities are not known, Margaret Cole, head of enforcement at the FSA, said that she had been allocated funding to increase manpower this year and had recently made some specialist hires.
“We're about to announce some people from really good places,” she said.
Since joining the FSA from White & Case, an American law firm, in 2005, Ms Cole has shaken up the enforcement division, which is responsible for investigating and prosecuting market abuse.
About one third of the division's staff has left. Her new recruitment drive should see the division's headcount increase this year from fewer than 300 to about 340. Of those, roughly 80 people are involved in insider-dealing cases.
Ms Cole has already made one big hire this year: David Kirk, a respected senior prosecutor, came from the Crown Prosecution Service (CPS).
The recruitment of Mr Kirk, a former fraud prosecution chief, brought a wealth of experience in fighting criminal cases. According to one fraud lawyer, he and Ms Cole make a “formidable” pairing.
Other recruits from leading law firms, such as Clifford Chance and Linklaters, have added much-needed commercial expertise to the division.
The FSA's enforcement division has stepped up its activity dramatically since last year. It expects to bring five new insider-dealing prosecutions before the end of 2009.
Last week, six people were arrested in raids at eight properties.
The FSA refused to give details of the arrests, except to say that they were in connection with a suspected organised insider-dealing ring and were independent of two similar co-ordinated raids last year.
As with earlier operations, the FSA team was accompanied by the City of London Police, whose officers make arrests before handing cases to the FSA.
Ms Cole is confident that her revamped team of criminal barristers, former Serious Fraud Office investigators and forensic specialists will make the cases stand up.
The FSA has also made significant technological advances in its fight against market abuse. Its new Digital Evidence Unit, a team of ten specialist investigators, is responsible for stripping and analysing computers, BlackBerrys and other electronic devices seized from suspected insider dealers.
Ms Cole acknowledges that there is much more to be done in the fight against insider dealing, but her team has already secured one crucial success.
In March, the FSA won its first two criminal convictions for insider dealing and its first custodial sentence.
Christopher McQuoid, a former senior lawyer at TTP Communications, was jailed for eight months after a jury found that he had tipped off his father-in-law about an upcoming takeover offer for the company.
James William Melbourne, the father-in-law, was convicted of knowingly using inside information to purchase thousands of shares and was given an eight-month suspended sentence.
It was a huge victory for the FSA. David Corker, a criminal lawyer at Corker Binning, said that it had “enhanced the regulator's image as an effective prosecutor of financial crime”.
The FSA has been criticised for prosecuting easy targets and its critics argue that it should be focusing its attention on repeat offenders rather than small-time opportunists.
Ms Cole said: “There is no such thing as an easy criminal case.”
Market abuse at large City institutions would not be overlooked, she said.
So far, three sets of arrests relating to suspected organised trading rings have been made but no charges have followed.
Call for tougher policy
An expert on fighting fraud and money laundering says that the FSA has consistently missed chances to prove that it is serious about tackling City crime.
Writing in the latest issue of Compliance Monthly, Rowan Bosworth-Davies, who runs a fraud-prevention consultancy, says that wrongdoers should be prosecuted in the criminal courts, rather than merely being fined by the regulator.
“Criminalising City wrongdoers is one of the most effective means of deterring white-collar crime,” he says.
“Once a City player has received a criminal conviction, it places him in the same social milieu as a burglar, thief or benefit cheat and he can never take his place in the financial sector again. Merely imposing a regulatory fine does nothing more than attract sympathy from his colleagues.”