The Office of the Consumer Protection Board (OCPB) says it needs two weeks to verify a complaint filed on Friday by True Corporation alleging unfair business practices by mobile leader Advanced Info Service Plc (AIS).
True alleged AIS blocked its second-generation (2G) mobile customers who wanted to sign up for True's 3G and 4G wireless broadband services from accessing True's call centre. Blocked calls were reported in many provinces.
The consumer protection agency, under the supervision of the Office of the Prime Minister, will submit its findings to the National Broadcasting and Telecommunications Commission (NBTC) and the Consumer Protection Police Division for further scrutiny.
Suvit Vijitsopa, director of the OCPB's contracts division, said True, through TrueMove H Universal Communication representative Suphasorn Honchaiya, filed the complaint with the OCPB on Friday along with a batch of documents and 10 video clips.
True alleged AIS might have violated consumers' privacy and rights to access telecommunications services.
"We'll verify this case before submitting our suggestions to the NBTC and the Consumer Protection Police Division for further scrutiny," Mr Suvit said. "It's too early to say whether AIS has violated criminal law."
Mrs Suphasorn, however, said True strongly believed AIS and its subsidiary had engaged in unfair business practices, violating the Computer Crime Act and the Telecommunications Business Act.
True said AIS must expedite the migration of its existing 11 million 2G customers on the 900-megahertz network to its 3G system before the network was shut down after True and JAS Mobile Broadband made their payments for their 900MHz licences.
The 900MHz spectrum was previously used by AIS under a concession to provide 2G mobile service. That concession expired last September.
The NBTC brought the 900MHz spectrum to auction last December to provide 4G service. True and JAS Mobile Broadband both won licences.
Mrs Suphasorn said True had received complaints from AIS's 2G users who were unable to contact True's 1331 call centre in many provinces.
The complaints fall into three categories — outgoing calls by AIS 2G users to True's call centre that were immediately cut off; outgoing calls to True's call centre that were redirected to the AIS call centre and then cut off; and outgoing calls that were redirected to the AIS call centre to hear AIS's promotional campaign before being transferred to True's call centre.
However, AIS senior vice-president Wilai Kiangpradoo insisted the company had never blocked its customers from accessing other telecom networks or any specific destination numbers.
She stressed AIS customers could call to all numbers as usual.