The details around the investigation of UBS by the Swiss bourse remain sketchy. Reuters reports that the investigation is into "whether UBS may have violated rules on releasing news last year when it announced a major restructuring and a settlement of Libor-related claims."
UBS says there is "no basis" for the investigation.
It's possible to piece together some details about what may be the subject of the investigation. And it seems that it may stem from leaks to a financial journalist.
Apparently, Switzerland has something close to what we know as Reg FD here in the United States. Reuters says "ad hoc publicity rules require companies to inform the market promptly of developments that could affect the price of their securities."
On Oct. 30, 2012 UBS put out a press release titled, "UBS announces strategic acceleration from a position of strength."
It announced a reduction in risk-weighted assets, the elevation of Andrea Orcel to lead the investment bank, the removal of Carsten Kengeter from the executive board and his shift from co-head of the investment bank to managing the exit from non-core businesses, the exit from certain fixed income lines of business, a renewed focus on wealth management, and a sizable headcount reduction.
(Read also: Stop freaking out about the JPMorgan deal)
This did not come as a surprise to anyone paying attention to UBS. A week earlier, on Oct. 23, Daniel Schafer of the Financial Times reported that "UBS is planning further drastic cutbacks in its struggling investment bank as Switzerland's largest bank by assets accelerates a retreat to its more profitable wealth management business."
"The move will prompt the loss of several thousand jobs in the investment bank and in support functions across the group, people close to the situation said," Schafer reported.
Schafer also reported that in "the investment bank, UBS is eying to exit further capital-intensive areas in fixed income trading such as long-end flow rates and global correlation trades."
Three days later Shafer was in the paper with another story with even more details.
"The non-core operation will be headed by Carsten Kengeter, current co-head of the investment bank, and will be wound down over time, two people close to the situation said," Shafer reported. "This summer, Mr Ermotti brought in dealmaker Andrea Orcel to become co-head of the investment bank alongside Mr Kengeter. Mr Orcel will take sole charge of the remaining investment bank."
A third FT story, by Daniel Schäfer in London and James Shotter in Zurich, reiterated this reporting and added some additional details.
(Read also: What happens next at the UBS investment bank?)
In others words, several days before the official announcement, The FT's Shafer had most of the crucial changes coming to UBS. While we don't know how Shafer learned these details, it's reasonable to suspect that top executives with access to the information were leaking it to him.
If this is the subject of the Swiss Bourse investigation, it seems very misguided.
The purpose of mandatory disclosure laws is to prevent privileged access to information that would result in some investors having an unfair advantage over uninformed investors. Leaking advance word of coming changes to a newspaper reporter might not fit within the letter of the law but it certainly doesn't create an unfair informational advantage for anyone.
Perhaps, however, I'm biased here. After all, I'm a reporter. I think speaking to reporters is a very good way for companies to communicate their intentions to investors and to the market.
It may even be more fair than filing press releases with securities regulators, which almost always creates a delay between the time information reaches professional traders and the time it reaches retail investors (who have to wait for journalists to write up what was in the official filing).
—By CNBC's John Carney. Follow him on Twitter @Carney