The news gathering technique appears more widespread than the Goldman incident, which was first reported by The New York Post. A preliminary analysis at Bloomberg revealed that “several hundred” reporters had used the technique, a person briefed on the analysis said. (Bloomberg employs more than 2,400 journalists worldwide. A spokesman declined to comment on the analysis and said no reporters had been fired.) 
 
 There are also fears that the monitoring may have gone beyond Wall Street. Banking regulators at the Federal Reserve are examining whether their own employees were subject to tracking by Bloomberg reporters, according to people briefed on the matter. A spokeswoman for the Fed declined to comment. 
 
 There are now more than 315,000 Bloomberg terminal subscribers worldwide who rely on the desktop computer for research, trading, communication and a constant stream of financial information and news. 
 
 But as it turned out, what the subscribers were doing was not always confidential. Bloomberg reporters used the “Z function” — a command using the letter Z and a company’s name — to view a list of subscribers at a firm. Then, a Bloomberg user could click on a subscriber’s name, which would take the user to a function called UUID. The UUID function then provided background on an individual subscriber, including contact information, when the subscriber had last logged on, chat information between subscribers and customer service representatives, and weekly statistics on how often they used a particular function. A company spokesman said both of those functions had been disabled in the newsroom. 
 
 Terminals never allowed journalists to see specific securities or trades, but even general hints of what users are searching could provide a glimpse into Wall Street’s thinking — powerful currency in the competitive world of financial journalism. Daniel L. Doctoroff, chief executive of Bloomberg L.P. and a close confidant to the company’s founder, Michael R. Bloomberg, said in a memo to employees that “client trust is our highest priority and the cornerstone of our business.” Mr. Bloomberg stepped away from day-to-day operations when he became mayor of New York City. 
 
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 Last month, the company further centralized its data security efforts, including appointing Steve Ross, a senior executive, to the newly created role of client data compliance officer. 
 
 “To be clear, the limited customer relationship data previously available to our reporters never included access to our trading, portfolio, monitor, blotter or other related systems or our clients’ messages,” Mr. Doctoroff said. He posted a damage control message to clients on the Bloomberg terminal and blog, calling the reporting practice a “mistake.” 
 
 Similar problems, which became public on Friday, started at JPMorgan Chase last summer, when the bank suffered a multibillion-dollar trading loss. Some Bloomberg reporters called the bank, people briefed on the call said, to question whether the traders responsible for the loss had been fired. They cited the fact that the traders had gone silent on the terminal. The bank, the people said, objected to the reporting technique, but did not formally reach out to Bloomberg executives to complain. Yet bank officials soon discovered that other Bloomberg reporters were using the approach on other stories unrelated to the trading loss. 
 
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 When Goldman raised the issue with Bloomberg last month, the media company dispatched senior sales executives to Goldman’s Lower Manhattan headquarters, according to people briefed on the matter. The Bloomberg officials assured top bank executives, including Gary D. Cohn, the firm’s president and chief operating officer, that the problem would be resolved. “We brought this matter to the attention of the news organization, and senior management at the company assured us that they were taking immediate measures to address the problem,” a bank spokesman said. 
 
 Matt Winkler, editor in chief of Bloomberg News, also contacted Goldman to apologize for the incident. In a meeting on Friday, he reminded reporters of the company’s policy about terminal use and the employee confidentiality agreement. 
 
 Jonathan Corpina, a managing partner at Meridian Equity Partners, said the incident was a reminder that nothing — not even the seemingly secure Bloomberg terminal — was private. “It concerns people that what they are doing is being watched and monitored by people who shouldn’t be watching and monitoring it,” Mr. Corpina said. 
 
 Mr. Bloomberg founded Bloomberg L.P. in 1982 as a financial information company. The company had revenue of $7.9 billion in 2012 and its high speed, data-splicing terminals occupy a prominent spot on traders’ desks. Even though Bloomberg News has gained prominence, counting the weekly magazine Businessweek among its assets, about 85 percent of the company’s revenue comes from its terminals. That business provides for generous employee perks, and cushions Mr. Bloomberg’s $27 billion fortune. 
 
 In the early 1990s, when Bloomberg L.P. had just started to build its news division, reporters were encouraged to leverage the terminals as a way to get a leg up on the competition, said several former employees who would discuss practices only anonymously. Reporters often went on sales calls to talk to banks and hedge funds about the news division to help the company sell terminals. The practice became much less pervasive as Bloomberg became an established news outlet, although many Bloomberg veterans still consider the news division solely a means to sell more terminals. 
 
 Thomson Reuters, which sells a desktop financial data product that competes with Bloomberg and, like Bloomberg, employs thousands of news journalists, promptly seized on its rival’s headache. “Thomson Reuters Financial and Risk business and Reuters division operate completely independently with reporters having no access to nonpublic data on its customers, especially any data relating to its customers use of its products or services,” said Yvonne Diaz, a Thomson Reuters spokeswoman. ||||| The information appeared to concern general functions used by the officials and the frequency with which those functions — such as looking at a bond, equity markets or news — were accessed. The source said all Bloomberg journalists who knew of this capability of the terminal would have had access to the usage information of the officials. However, CNBC has no information that the data were either used by the employees for journalism or shared inappropriately. 
 
 (Read More: Privacy Breach on Bloomberg Terminals ) 
 
 In response to queries that Bloomberg journalists had access to officials data usage, a Bloomberg spokesman said, "What you are reporting is untrue" but declined to respond when asked what specifically was inaccurate. He also would not say whether the company had investigated journalists' access to this information. 
 
 CNBC is a competitor of Bloomberg in reporting and distributing business news on the web and on television. 
 
 The issue of Bloomberg journalists' access to individual data from the terminals was revealed in recent days when a reporter called a Goldman Sachs Group employee inquiring about a partner's employment status and noting the partner had not logged on to the terminal lately. 
 
 The incident prompted a complaint from Goldman and led Bloomberg to terminate the ability of reporters to monitor subscribers. 
 
 (Read More: Wall Street: How Much Does Bloomberg Know?) 
 
 In a statement on its website, Bloomberg said, "Having recognized this mistake, we took immediate action. Last month we changed our policy so that all reporters only have access to the same customer-relationship data available to our clients." 
 
 The former Bloomberg employee who worked in the editorial section recalled calling up the information on Fed Chairman Ben Bernanke and Treasury Secretary Tim Geithner "just for fun" and displaying the information to new recruits "to show how powerful" the Bloomberg terminals were. 
 
 The former employee said he recalled seeing the functions used by the Fed Chairman and Treasury Secretary and the number of times those functions had been used. The person did not recall which specific functions he saw, but said it would have been at a broad level. For example, he said it would likely have been information that the official accessed a page such as global equity indexes, though not which markets specifically. He said it also could have included information that the user looked up bond spreads, but the information would not have shown what specific bonds were searched by the user. 
 
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 Still, with thousands of functions, the information could apparently get quite specific. And knowing how often a user looked up individual information and how often the user was logged in could provide valuable information. 
 
 A JPMorgan Chase source told CNBC that, "Multiple Bloomberg reporters very openly were using terminal login data to determine when traders were suspended and/or let go — during the London Whale situation, as well as during other rounds of layoffs." 
 
 A Quartz story (www.qz.com) said Bloomberg employees had accessed a transcript of a call of former Fed Chairman Alan Greenspan to the company's help desk. The story said the information was not used in any editorial pieces written by journalists. 
 

– Bloomberg LP operates both a multi-platform media organization, Bloomberg News, and a computer system, Bloomberg Terminal, that bankers and traders use to monitor market data. The problem: Bloomberg News reporters can see how and when any customer has been using a terminal, and now it turns out they have been using that access to snoop on Wall Street and break news, the New York Times reports. And it may have gone even further than just traders: a former Bloomberg staffer now says he also accessed the terminals of Ben Bernanke and Timothy Geithner, according to CNBC. The issue was first discovered when a Bloomberg reporter asked Goldman Sachs if a partner had recently left the firm because he hadn't recently logged into his terminal, the New York Post revealed. JPMorgan claims Bloomberg may have used data from terminals to break the "London Whale" scandal, the Post reports. The Times says "several hundred" reporters have used the technique, gaining access to 315,000 subscribers worldwide. Bloomberg has called the news-gathering process "a mistake," and has cut off its journalists' access, reports the AP. But the damage may already be done: the terminal is Bloomberg's primary money-maker, with firms paying around $20,000 a year to use it, and Wall Street is not happy.