Mr William Ong > Allen & Gledhill LLP > Singapore, Singapore > Lawyer Profile

Allen & Gledhill LLP

Work Department

International Arbitration, Litigation, Restructuring & Insolvency


Co-Head of the Firm’s Litigation & Dispute Resolution Department


William’s areas of practice encompass international arbitration, banking litigation, corporate insolvency and restructuring as well as corporate litigation.

William has substantial experience in banking litigation, financial and securities-related disputes, and regularly acts in disputes involving structured products, margin trading, valuations, guarantees and enforcement of security. He is also actively involved in representing clients in corporate disputes, such as shareholder and directors’ disputes as well as joint venture disputes.

He also practises in the field of licensing, distribution and franchise disputes, and they span different industries ranging from computer software to boiler technology to pharmaceutical products. William has special interest in the field of assessment of damages and valuation methodology, as he believes that most disputes would be ultimately concerned with damages and its assessment – he is familiar with the technical and legal aspects of this area which is valued by clients.

William is effectively bilingual in English and Mandarin and has rendered expert opinions before the English courts and the courts of the People’s Republic of China.

Called to the Singapore Bar in 2000 and joined the Firm in the same year.


English, Mandarin


Fellow, Singapore Institute of Arbitrators.


Graduated from the National University of Singapore with an LL.B. (Hons) degree in 1999.

Lawyer Rankings

Singapore > Dispute resolution: local firms

Allen & Gledhill LLP may be light at Senior Counsel level with intellectual property specialist Stanley Lai SC its sole practising SC. Despite this, the firm maintains a sizeable market share of major disputes, including Singapore International Commercial Court (SICC) and Singapore Court of Appeal cases. Other key partners include William OngVincent Leow, white-collar crime and investigations specialist Jason Chan, employment disputes expert Tay Yong Seng and Peh Aik Hin. Tan Kai Liang is also rated.

Singapore > Intellectual property: Local firms

At Allen & Gledhill LLP, Stanley Lai, SC leads a ‘very experienced team‘ of intellectual property specialists, patent attorneys and design and trade mark executives who handle a wide range of contentious and transactional IP matters in the biotechnology,  pharmaceuticals,  software and entertainment sectors. Lai primarily focuses on contentious IP, particularly in relation to patent prosecution, passing off, copyright infringement and data protection issues. Pei Lin Low is ‘a safe pair of hands‘ and ‘an experienced patents lawyer‘; she also assists with the management of patents, trade marks and design portfolios. ‘Strong all-round IP lawyerGloria Goh advises on regulatory aspects in the pharmaceuticals, cosmetics and food industries as well as acting in disputes involving trade marks, copyright, domain names and infringements claims. William Ong is noted for disputes involving trade secrets and confidential material.