The editor-in-chief of Bloomberg News apologized on Monday for his reporters accessing client information obtained from the company’s financial terminals as the Federal Reserve begins to look into the snooping.

The apology comes after reports surfaced last week revealing Bloomberg journalists accessed client log-in data at the Fed, Treasury Department, Goldman Sachs (GS) and other firms.

“Our reporters should not have access to any data considered proprietary. I am sorry they did. The error is inexcusable,” Matthew Winkler, Bloomberg’s editor-in-chief, wrote in an op-ed early Monday.

Bloomberg said it immediately changed its policy last month to prohibit reporters from accessing customer information.

Investors and market observers rely on Bloomberg’s terminals and similar platforms from Thomson Reuters (TRI) and FactSet (FDS) to receive real-time data on financial markets and to track news stories. Bloomberg terminals rent for over $20,000 a year and are highly regarded by market participants.

Goldman complained to Bloomberg about the matter after a reporter from the news service asked a Goldman exec if a partner had recently left the firm, noting that he hadn’t logged onto his Bloomberg terminal in some time, the New York Post reported.

Meanwhile, officials from the Fed told FOX Business they have concerns as to whether there’s been any inappropriate access by Bloomberg. “We are looking into this situation and have been in touch with Bloomberg to learn more,” said a Fed spokesperson.

“Our editorial and reporting standards have been among the most stringent in the business for more than 20 years. We apologize for our error as it does not reflect on our culture or our heritage,” Winkler wrote.

However, Winkler said Bloomberg reporters only had access to a user’s login history, when the login was created, help-desk inquiries and “high-level types of user functions on an aggregated basis, with no ability to look into specific security information.” Winkler compared this with being able to “see how many times someone used Microsoft (MSFT) Word vs. Excel.”

The Bloomberg editor said the access was originally allowed to help reporters understand what topics clients were interested in having covered.

“At no time did reporters have access to trading, portfolio, monitor, blotter or other related systems,” Winkler said, adding that reporters did not have access to client messages and securities searches.

Susan Garraty contributed to this story.

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