The law firm hired by Siemens to investigate corruption claims had found evidence of violations across the company and in several countries, an Associated Press report said.
In a summary of the report, Debevoise & Plimpton said it examined business transactions that took place between 1999 and 2006.
Siemens said in a statement that the investigation by Debevoise & Plimpton's into several key divisions showed that 'domestic as well as foreign compliance regulations have been violated.'
Siemens had been rocked by claims at the company involving ex-managers who are accused of bribery and fraud. Several different countries, including the US, Switzerland, Italy and Greece, have launched investigations.
Siemens also is being investigated in China, Hungary, Israel, Russia, Norway and Indonesia.
Investigators are probing allegations that employees paid hundreds of millions of euros in bribes to land telecom deals.
Siemens has acknowledged dubious payments in the corruption case that came to light last year of to â‚¬1.3 billion (US$2.07 billion), the report said.
'The violations in question reflect not only outright incidents of corruption, but, in many cases, violations of regulations pertaining to internal controls and the accuracy of documentation,' the report said.
The investigation focused on the company's then-communications division, as well as its power generation, power transmission and distribution, transportation systems, industrial solutions and services and its medical solutions.