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Siraprapha Claassen



Siraprapha (Khim) Claassen is a consultant in Tilleke & Gibbins’ intellectual property (IP) and regulatory affairs groups. With her practice focusing mainly on pharmaceuticals and life sciences, Khim serves international clients in these industries in contentious issues, including pharmaceutical and IP litigation, and noncontentious issues, including regulatory affairs, clinical trials, healthcare personnel (HCP) dealings,  contract and advertising review, data protection, and compliance matters.

In addition to her role at Tilleke & Gibbins, Khim currently serves as Innovation Counseling Manager for the National Innovation Agency (Public Organization) (NIA), an autonomous agency under the supervision and policy guidance of the Ministry of Higher Education, Science, Research and Innovation. Khim’s duties and responsibilities at the NIA include managing and supervising IP promotion and support programs, conducting IP valuation, and liaising with partner organizations with regard to IP and innovation.

Khim is a graduate of the New York University School of Law (LLM with distinction), Boston College Law School (JD, cum laude), and the University of Chicago (BA in Economics with honors).


  • Advised a pharmaceutical client on various IP issues, such as product liability, government advocacy on new regulations, compulsory licenses, new laws (Patent Act, Drug Act), and trademark registration.
  • Acted as counsel to a major pharmaceutical company, which representation included liaising with the Thai FDA on marketing compliance issues, verifying that the client’s marketing activities were in compliance with the complex regulations governing pharmaceutical practice in Thailand, and preventing and mitigating risk and loss.
  • Represented a multinational pharmaceutical company in patent infringement litigation against a local generic company.  Managed a major pharmaceutical-related patent during a trial on patent infringement.
  • Prosecuted pharmaceutical patent litigation against various local producers of infringing generic drugs.
ABOUT Siraprapha






    LLM, New York University School of Law

    JD, Boston College Law School

    BA, University of Chicago


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