Thailand's True Move has filed a criminal complaint against rival DTAC, alleging that its ownership structure is in violation of foreign investment laws.
True Move has asked the nation's Crime Suppression Division to initiate proceedings against DTAC on the grounds that foreign companies, including majority owner Telenor, allegedly own over 70% of the operator.
In a statement, True Move said a recent house of representatives report held that operators, as infrastructure services providers, should be no more than 49% controlled by foreign entities.
The company accused DTAC of spreading shares among nominees in a bid to conceal the fact that it is foreign-owned. True Move even alleged a national security risk of having telecom infrastructure in foreign hands.
But Telenor and DTAC insisted to the Bangkok Post the structure is in compliance with Thai laws.
Under this structure, Telenor Asia owns 41% of DTAC. A further 15% is owned by Thai Telco Holdings, which is itself 49%-owned by Telenor Asia.
Telenor also told the report that True Move cited still needs to be cleared by parliament, and that the operator is willing to comply with any changes to the law that do get made.
DTAC in April filed a lawsuit in an attempt to block True Move's planned 3G partnership with CAT, alleging that the deal violates rules on public-private partnerships.