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Florentino Perez, the Spanish billionaire chairman of the ACS construction company, is joining plaintiffs in a criminal probe of Iberdrola SA and alleged corporate spying.

Iberdrola hired an off-duty police commissioner back in 2009 to spy on Perez and help thwart a hostile takeover by ACS, Spanish website El Confidencial reported on Monday. Perez, who also is chairman of the Real Madrid football club, decided to join the criminal case, state-news agency EFE said in a report whose content was confirmed on Monday by an ACS press officer.

El Confidencial reported that Iberdrola hired Jose Manuel Villarejo in early 2009 to gather “compromising” personal information on Perez shortly after ACS boosted its stake in the Spanish power utility to 12.6%. Perez is the biggest shareholder in the firm, whose full name is ACS, Actividades de Construccion y Servicios.

Iberdrola declined to comment, according to a press officer who referred to a previous statement in which the company said it had opened an internal investigation into allegations regarding Villarejo and Iberdrola. The ACS press officer declined to comment further.

According to El Confidencial’s reports, Villarejo worked closely with Iberdrola’s head of security, Antonio Asenjo, who reported directly to Ignacio Galan, who was chairman of the utility at the time and continues to hold the post. Galan is not facing any accusations linked to the scandal. Asenjo was let go last month.

Iberdrola is the second major Spanish company tainted by spying scandals involving Villarejo. Banco Bilbao Vizcaya Argentaria SA was declared a criminal suspect over hiring Villarejo to allegedly spy on politicians, corporate rivals and journalists. On Nov. 15, a judge placed BBVA’s long-time chairman Francisco Gonzalez under formal investigation for bribery and unlawful disclosure of secrets.

Spanish media has been riveted by the stories of Villarejo, who has been in prison since 2017 after disclosures that he ran private investigation services while at the same time holding a high-ranking police job. Villarejo has denied wrondoing and has said he worked as an undercover policeman.

The scandal led BBVA’s Gonzalez, who retired from the bank late last year, to step down from his remaining positions, such as honorary chairman.

To contact the reporter on this story: Rodrigo Orihuela in Madrid at rorihuela@bloomberg.net

To contact the editors responsible for this story: Charles Penty at cpenty@bloomberg.net, Todd White

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