FRANKFURT, Germany (AP) -- The former chief executive and board chairman at German industrial conglomerate Siemens could be fined for a violation of his oversight duties.

Prosecutors said Friday that they have opened administrative proceedings against Heinrich von Pierer, but they stopped short of launching a criminal investigation against him, citing lack of evidence over corruption and bribery at the Munich-based company.

Administrative proceedings can lead to fines but not imprisonment.

Munich prosecutors said in a statement that they have opened proceedings against von Pierer and other former company officials on suspicion of possible ''violation of duty of oversight in companies.''

The statement did not identify the other ex-officials, saying only that currently active management and supervisory board members were not among them.

Von Pierer's lawyer, Winfried Seibert, said in a brief statement that his client ''takes note of this decision and continues to be ready to cooperate fully with prosecutors.''

Siemens has acknowledged dubious payments in the corruption case that came to light last year of up to 1.3 billion euros ($2 billion).

Von Pierer has denied any wrongdoing. He served as Siemens CEO until 2005, then became head of its supervisory board. He stepped down last year -- as did his successor as CEO, Klaus Kleinfeld.

Siemens on Friday welcomed the announcement, and stressed that it will cooperate.

''With a view to possible consequences of the investigation for the company, Siemens will examine all necessary measures'' to defend its interests, it said in a statement.

Siemens, which makes everything from wind turbines to trams, agreed in October to pay a 201 million euro ($309 million) fine to bring an end to some legal proceedings related to the investigation.

Siemens' own investigation has found evidence of violations across the company and in several countries.

The first trial related to the scandal is to open in Munich on May 26. A former top-level sales manager faces charges fraud for his role in setting up a complex network of shell corporations allegedly used to siphon off company money.

Shares of Siemens fell nearly 3 percent after Friday's announcement to 74.25 euros ($113.95).