* Salvatore Ligresti suspected of obstructing Consob
* Ligresti declines to comment
* Fondiaria-SAI shares underperform
MILAN, July 15 (Reuters) - Salvatore Ligresti, the main owner of Italy's largest auto insurer Fondiaria-SAI SpA , is being investigated over allegations he obstructed market regulator Consob, judicial sources said on Friday.
The Milan prosecutor is looking into whether Ligresti withheld information from Consob about meetings he had with French businessman Vincent Bollore and a top Italian banker on French insurer Groupama taking a stake in the Italian insurer, they said.
The banker is Alessandro Profumo, the former chief executive of UniCredit which is taking a 6.6 percent stake in Fondiaria-SAI via a capital increase after Groupama's interest was rebuffed, they said.
The judicial sources confirmed reports in La Stampa and Il Messaggero dailies on Friday.
A spokeswoman for Ligresti declined to comment.
The sources said magistrate Luigi Orsi has asked Ligresti to answer their questions next Thursday.
In March, a court in the Italian city of Florence ordered 79-year-old Ligresti to stand trial on corruption charges.
Efforts to support the loss-making and weakly-capitalised Fondiaria-SAI began last year.
In the autumn, Bollore built up a 5 percent stake in Premafin , which is controlled by the Ligresti family and is the main owner of Fondiaria-SAI.
Subsequently, Groupama said it wanted stakes of up to 20 percent in Premafin and Fondiaria-SAI but was told by Consob it would have to bid for both companies, something which Groupama was not keen to carry out.
The Ligrestis and Groupama ended talks in March.
Instead, Fondiaria is carrying out a 450 million euros ($637 million)rights issue which ends on Friday. UniCredit is buying rights in the issue from Premafin and will invest a total of 170 million euros for its 6.6 percent stake.
At 1316 GMT Fondiaria-SAI shares were down 1 percent, underperforming the STOXX Europe 600 insurance index which was down 0.34 percent. ($1=0.706 Euros) (Reporting by Manuela D'Alessandro, Writing by Nigel Tutt; Editing by Erica Billingham)