Kularb Kaew, Cypress Holdings, Cedar Holdings and Aspen Holdings - the four companies with direct and indirect holdings in Shin Corp - share an identical office address at Thai Wah Tower II, according to findings of the Business Development Department.

A classified department report obtained by The Nation showed the four companies all reside at Thai Wah Tower II 21/125-128.

The 10-page report is the result of a months-long investigation that commenced on February 17.

It looked into the Thai and foreign shareholdings of the four companies, their sources of funds and management. Company documents were looked at as were their commercial banks and related agencies. Individuals were questioned.

The Commerce Ministry is yet to release the report but has set up a new investigation team chaired by deputy permanent secretary Yanyong Phuangrach.

He expected that investigation would be wrapped up within two months, or shortly after the general election.

Critics accuse Singapore's Temasek Holdings of taking over Shin Corp using nominee companies.

One critic quoted from Temasek's website that claimed the state investment arm owned 96 per cent of Shin Corp.

In a statement yesterday, Temasek said its direct holding in Shin Corp was 44 per cent, through Aspen. The other 52 per cent was owned by Cedar, which has Kularb Kaew and Siam Commercial Bank as major shareholders.

In its quest to discover if Kularb Kaew was a Temasek nominee that, together with Thai investors, owned 96 per cent of Shin Corp, the department found Temasek helped Pong Sarasin and Suphadej Poonpipat buy Kularb Kaew shares.

Based on documents from Siam Commercial Bank - where transactions between Kularb Kaew, Cedar and Cypress took place - the department found a sum of Bt131.54 million was transferred to a Kularb Kaew account from a Cypress account at the bank's Ratchayothin Branch.

The amount was equivalent to the value of shares held by Pong, one of the company's seven founders, the department noted.

Meanwhile, the department found Suphadej borrowed Bt32.86 million from SCB to finance Kularb Kaew. Cypress guaranteed the loan.

"Regarding money coming to Cypress, money from Cypress to Kularb Kaew, Cypress transfers to back Suphadej's loan and Cypress payment for shares in Cedar, all was from Fullerton Private, a unit of Singapore's Temasek," the department said in the report.

Referring to Surin Upatkoon's investment in Kularb Kaew, the department found Surin received Bt2.72 billion from HSBC Bank.

The bank informed the department it was asked by Surin to transfer the money on March 10 from an account belonging to Fairmont Investments Group. Fairmont, registered in the British Virgin Islands, has Greenland Co as its authorised manager. Greenland transferred that authority to Surin.

Since the department started its investigation, it sought to question 10 individuals involved in the four companies. Eight submitted to interviews, including Pong and Suphadej. Not submitting to questioning were S Isawaran and Chai Yue Joo, two of three people authorised to sign bank accounts on behalf of Kularb Kaew, Cedar and Cypress.

Pong told the investigation he was persuaded by Temasek representative Isawaran to buy Kularb Kaew shares from Somyot Sutheerapornchai, a lawyer for Cypress.

He told the department he agreed to hold preferred shares - despite their inferior status compared with common shares - due to a fixed dividend of 3 per cent a year which was close to current commercial deposit rates.

Moreover, there was a condition the preferred shares could be converted to common shares within one year. Pong was approached to be Shin Corp chairman, too.

Meanwhile, Suphadej explained he spent between two and three weeks considering an investment in Kularb Kaew. He decided to invest because he was an independent director at Advanced Info Service, a flagship company of Shin Corp.