Swiss bourse probes UBS over ad hoc publicity

ZURICH (Reuters) - The Swiss bourse has opened an investigation into whether UBS may have violated rules on releasing news last year about a major restructuring and settling LIBOR-related claims, it said on Thursday.

It said it was not clear how long the investigation by its SIX Exchange Regulation arm would take, and it would provide no more information while the case was still open.

UBS dismissed the allegation, saying: "There is no basis for this investigation." It said it took its disclosure responsibilities seriously and had complied with all legal requirements as well as upheld its own standards for disclosure quality and timeliness.

(Reporting by Michael Shields. Editing by Caroline Copley.)