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William Onishi

Senior Associate

William has a broad range of specialist legal, accountancy and taxation knowledge. He builds long lasting relationships with individuals and small to medium size businesses through open and transparent communication and by achieving excellent results.

William holds a Masters of Laws Degree & Legal Practice from the University of Technology and a Bachelor of Commerce Degree (major in Accountancy) from the University of Wollongong and is admitted as a legal practitioner in The Supreme Court of NSW and The High Court of Australia.  While William was a member of The NSW Young Lawyers Association he was awarded the NSW Young Lawyer of the Year Award by Justice Harrison.

Since 2003 William has extensive experience working in the areas of Commercial and Corporate Law, Taxation Law, Insolvency Law, Family Law, Commercial Litigation, Employment Law, Property Law and Wills and Estates.

William also holds an Accounting degree and has previously practised as an accountant in both small and large international chartered accounting firms.

William approaches each client’s matter in a considered and professional manner.

William was born and educated in Australia and is fluent in Japanese.

Career Highlights

  • Represented a large cleaning business in the airline industry in a $10 million sale. This involved multiple complex legal negotiations, meticulous drafting of legal documents and detailed assessment of assets and financial considerations.
  • Acted for investors in a matter involving income tax treatment of investments in retirement villages. This involved representation in the Federal Court and in the High Court of Australia.
  • William has extensive experience in all aspects of commercial litigation and has successfully acted in trademark, strata, motor vehicle, debt recovery, estates, real property, franchise, corporation, contract, employment and construction disputes.
  • Successfully appealed a family property dispute for $4.8 million in the Family Court of Australia.
  • Successfully appealed the repayment of stamp duty to Revenue NSW in a case involving the First Home Owners Grant
  • He has extensive experience in insolvency law, acting for individuals, small and listed companies and banks to wind up or bankrupt defaulting customers.
  • William has drafted and registered many family trust deeds, including for high-net-worth individuals and regularly acts for individuals in obtaining Probate or Letters of Administration.
  • Has over 20 years of experience in general corporate and commercial matters for small to medium size companies and the Australian Government.

Call us to arrange a free 20 minute no obligation consultation that includes case evaluation and cost estimate.

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