Ngern Tid Lor Co will submit a petition to the Central Intellectual Property and International Trade Court demanding SET-listed Srisawad Power 1979 Plc (SAWAD) remove the latter's name and logo from all branches.
The automobile refinance and microfinance arm of Bank of Ayudhya said the move was aimed at preventing customer confusion.
The petition follows Tuesday's Supreme Court decision to postpone its verdict in an earlier legal case by Ngern Tid Lor against Srisawad, demanding the latter change the Srisawad name and logo.
The verdict delay was due to a change in Srisawad's lawyer, said Manida Zinmerman, a partner in Hunton & Williams (Thailand), Ngern Tid Lor's legal representative.
The case has been going on since 2009, with Ngern Tid Lor winning a verdict from the Central Intellectual Property Court in 2011.
However, the problem did not end there, and the similarity in the two brand names and logos continue to cause confusion as to whether they are the same company.
After listing on the SET last year, the former Srisawad Power changed its name to Srisawad Power 1979.
Ngern Tid Lor uses Srisawad Ngern Tid Lor in its logo, but both companies' logos, character fonts and sign colours still confuse customers.
"Some customers of the defendant, when they have problems, end up calling us instead out of confusion," said Piyasak Ukritnukun, managing director of Ngern Tid Lor.
"This has affected our business operations and opportunities in several areas very much."
He said many people mistakenly believe the two companies are with the same group or affiliated.
Mr Piyasak insists his company will continue using the Ngern Tid Lor name and Srisawad Ngern Tid Lor brand along with the logo, character font and sign colours.
Ngern Tid Lor has outstanding loans of 15 billion baht year-to-date, already achieving its full-year growth target of 20%.
However, it expects lower loan growth of 15% next year due to the larger base.
The company plans to open 40 new branches nationwide next year for a total of 423.
In the meantime, Srisawad Power director Thida Kaewbootta said the legal cases had no effect on the company's business, and Srisawad was considered a general name that everyone could use.
Srisawad or Si Sawat is a district of Kanchanaburi province.
However, the company is considering a rebranding, Ms Thida said without elaborating further.
Srisawad Power expects net profit, revenue and loan growth of 30% next year.
If that goal is achieved, outstanding loans will reach 15.6 billion baht at the end of 2016 from an expected 12 billion this year, Ms Thida said.
It also plans to purchase 1-2 billion baht worth of non-performing loans from other financial institutions next year and open 400 more branches nationwide for a total of 2,000.
SAWAD shares closed yesterday on the SET at 49.25 baht, up 1.25 baht, in trade worth 592 million baht.