The Aug 4 auction of the 1800-megahertz spectrum will technically be cancelled now that all three largest operators announced they would opt out.
The deadline for submitting the bidding documents ends at 4.30pm on Friday.
True Move, the second largest operator, told the National Broadcasting and Telecommunications Commission (NBTC) in April it would not join the bid, saying it had no need for new bandwidth.
It claimed the combined bandwidth and capacity it had at the moment could serve double the number of its existing customers.
Third-ranked Total Access Communication (DTAC) and market leader Advanced Info Service (AIS) issued statements to the same effect on Friday.
In DTAC's case, its CEO said DTAC already had enough bandwidth to support the growing needs of customers.
"DTAC has considered the auction carefully and concluded that DTAC currently has enough high-band spectrum to handle the growth of data services.
"Moreover, the auction conditions did not allow for long-term value creation for our customers and shareholders," CEO Lars Norling said in a statement.
AIS issued a statement shortly after, quoting CEO Somchai Lertsutiwong as saying the auction terms did not suit its needs.
However, the company left its options open, saying it would continue to monitor the development and any changes in the auction process.
All three companies assured their customers their services and capabilities would not be affected in any way by the decisions.
The NBTC has yet to make an official announcement but with all three players opting out, the auction apparently cannot continue.
The regulator planned to auction three blocks (2×15MHz each) with a reserve price of 37.45 billion baht, valid for 15 years at the auction. It was the first spectrum auction in three years after True Move and AIS each won 30MHz in 2015.
The bandwidth to be put on the block currently belongs to DTAC whose concession for it expires on Sept 15.
All bidders must deposit 1.87 billion baht as a bid guarantee to participate in the tender. If only one bid is received, the regulator will postpone the auction for 30 days and if no applications are received during the grace period, one concession will be auctioned to the bidder at a one-time increment of 75 million on the 37.45 billion reserve price.
In 2015, two licences were auctioned on the 1800MHz spectrum, each containing 30MHz of bandwidth.
True Move won the first slot between 1710-1725MHz for upload and 1805-1820MHz for download, while AIS won the second slot of 1725-1740MHz for upload and 1820-1835MHz for download.
The 1800MHz auction scheduled for Aug 4 is for three licences adjacent to the 2015 auction.
Shares of AIS gained 1.9% to 192.50 baht while TRUE shares advanced 2.3% to 6.75 baht against the 0.3% rise of the main index at 2.10pm. DTAC shares plummeted 6% to 46.25 baht as investors were not convinced it would have enough bandwidth to operate efficiently despite its assurances.
According to Bloomberg, analysts have said DTAC needed the spectrum. Ratings agency Fitch has said securing the 1800Mhz spectrum was "crucial" for DTAC because it had lost market share due to spectrum inferiority.
There has been some expectation that the regulator, the NBTC will ease the terms of the auction to make it a success. "We urge the regulator to introduce a spectrum roadmap for the release of lower band spectrum," Marcus Adaktusson, Telenor group vice president for public affairs, Asia, said in an email sent to Bloomberg.
