In 2012, the threat by US regulators to withdraw StanChart's dollar clearing licence led it to agree to pay $667 million to settle allegations of sanction breaches up to 2007. At the time, the DFS, then headed by Benjamin Lawsky, shocked the bank by accusing it of being a "rogue institution" whose actions left the US financial system "vulnerable to terrorists, weapons dealers, drug kingpins and corrupt regimes".
With shares in StanChart trading near 10-year lows, the latest investigations provide another big challenge for Mr Winters, who succeeded Peter Sands as StanChart's chief executive. It also indicates that even as US President Barack Obama pushes for sanctions against Iran to be relaxed in return for curbs on its nuclear programme, there are no signs of US regulators losing their zeal for pursuing past transgressions involving the Islamic republic.
The material reviewed by the FT depicts a bank — one of the few foreign lenders with a licence to operate in the country — determined to keep working with Iranian companies.
The status of numerous Iranian and Iran-connected entities was still being reviewed by StanChart as late as 2013, according to documents seen by the FT. These included entities that had internal "markers" and "blocks" placed against them, a way for the bank to flag up concern about links to Tehran.
Many accounts belonging to Iranian or Iran-connected entities were indeed closed by 2007, as StanChart promised. But some, like Bank Saderat — which had sanctions imposed in 2006, or Bank Sepah — still had open accounts with no markers against them. According to lawyers consulted by the FT, it is not illegal to hold accounts for entities under sanctions as long as they remain frozen.
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Clients generating revenue included IFIC Holding AG, which in August 2010 was identified by the US Treasury as the German arm of an Iran government-owned entity and put under sanctions. An internal StanChart performance report, dated March 2012, that records transactions with Iran-connected companies — labelled "Iran Group" — cites revenue for IFIC Holding AG.
Non-US banks such as StanChart are allowed to conduct transactions with companies on the US sanctions list provided no US persons are involved and they do not involve the American financial system. However, in 2010 the US tightened its sanctions regime, introducing measures that gave US regulators the power to punish foreign banks engaging with Iran even if the contested transaction did not involve the US financial system.
The move was a warning to companies that by choosing to do business with Iran they risk being cut out of the US financial system. Given the dollar's ubiquity, this risk has led many international banks to halt business with US-sanctioned entities altogether.
Top performing clients in the so-called "Iran Group" also included Mapna International FZE, a subsidiary of Mapna Group, a sprawling Iranian industrial conglomerate, according to documents seen by the FT.
Senior StanChart executives outlined one method to maintain the business in a note to staff dated October 2008, a day after the US placed the Export Development Bank of Iran on the sanctions list.
StanChart was keen to avoid "delay or financial loss" to its Iranian clients. "We are working with the Designated Parties [companies under US sanctions] to settle outstanding USD obligations in an alternative freely convertible currency", the memo says.
It adds that any foreign exchange deal to "convert the alternative currency into USD must be for the account of and in the name of the beneficiary and not for the account of the Designated Party, and any FX risk will be for account of the beneficiary".
While this technique — finding currencies other than the US dollar to conclude transactions with Iranian clients — may not have been a breach of US sanctions, a former member of the bank's Dubai team says it was "against the spirit of the sanctions".
An email written in 2009 by a senior StanChart manager in Dubai, seen by the FT, shows a list of potential target clients, including the National Iranian Oil Company, which at the time was under sanctions.
These potential new violations have angered a host of agencies, from the DoJ to the New York Fed and DFS. Although settlement talks have yet to begin, the bank is expected to be hit with harsh penalties — unless it can explain its conduct — because it is seen as a repeat offender, people familiar with the case say. In August 2014, New York's DFS fined StanChart $300 million for failing to resolve problems with its anti-money laundering compliance system. The regulator forced it to sell or shut as many as 8,000 small business accounts in the United Arab Emirates and banned it from clearing US dollar transactions for some Hong Kong clients.
Authorities are still in the process of obtaining information from the bank about the current probe, the people add. A deal, if it happens, could come at the end of this year or early in 2016.
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A whistleblower emerges
The FT has found that the US investigation into StanChart did not close after the 2012 settlement. Shortly after the deal was agreed, a whistleblower came forward with information that gave US regulators and law enforcement new ammunition against the bank, according to people familiar with the matter.
An internal StanChart document seen by the FT shows that the bank is again facing questions from regulators and law enforcement about its dealings with Iran, reaching back to at least 2005 — a period that had already been reviewed as part of the prior investigation.
A separate line of inquiry emerged from the authorities' investigation into BNP Paribas. Among the French bank's violations were transactions with Caspian Petrochemical FZE, an Iran-owned company based in Dubai, which acted as a front for an Iranian based energy group in Tehran, and was engaged in shipping liquefied petroleum gas.
Evidence from the BNP probe led investigators to believe that StanChart may also have breached sanctions in its transactions with Caspian Petrochemical FZE.
By March 2013 high-ranking StanChart executives were in denial about the gravity of the bank's alleged sanctions busting. At a press conference that month, Sir John Peace, who has chaired the bank for six years, called its actions "clerical errors or mistakes" and denied that the bank had "wilfully" breached sanctions. Shortly afterward he retracted his statement and apologised after a rebuke by the DoJ and the Manhattan district attorney's office.
Around the same time, an internal StanChart team worked alongside experts from Promontory — the financial consultancy that was recently fined $15 million in relation to its prior work with StanChart — to resolve a series of requests and subpoenas from US law enforcement authorities.
The teams also reviewed the due diligence done by the bank on clients at its Dubai branch — a particular focus of the US authorities' continuing inquiry — and researched whether existing clients were Iranian or had Iranian connections. The emirate has long been a convenient hub for Iranians and those wanting to do business with Tehran.
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Of particular interest to the authorities was the bank's online trading system, known as OLT3 (On-line Treasury), according to documents seen by the FT. It allowed approved customers to conduct trades online, including foreign exchange transactions. As StanChart's team gathered information to respond to US requests, it noted significant flaws in the system, to which Bank Saderat at one point had direct access.
The system did not record timing of logins by clients and provided no audit trail of client access, according to a document seen by the FT. It also indicates that a former Bank Saderat Iran employee with direct access to the OLT3 had left the bank and moved to a UAE company but kept the same user ID.
It is unclear whether StanChart reported this flaw to the authorities of its own accord. The document says: "all 'Iranian' clients who received direct access to the system were domiciled outside of Iran".
A former senior executive at StanChart, speaking on condition of anonymity, described a number of failings at the bank that led to the repeated probes. He described a "cavalier" culture, where management encouraged the sales staff to go after new business aggressively in frontier markets such as Iran and Iraq. The bank also failed to invest enough in compliance, he says.
StanChart had sometimes been tricked into dealing with Iranian entities, such as by a client with three passports who only showed the two non-Iranian documents to the bank, he adds.
But StanChart was also often let down by its technology. "The bank really isn't very good at technology and often the system really wasn't performing."
Former staff members of StanChart in Dubai have told the FT the bank had global policies in place and they had to turn down business because of those policies of not dealing with sanctioned entities.
But as he reported disappointing results in August, Mr Winters said he intended to overhaul the bank's culture and bolster its compliance operations, while warning of difficult times ahead.
In a possible signal of his priorities, one of Mr Winters' first trips was to meet Mr Lawsky in his New York office.