How I can help your business

• Advise on IP strategy and management across all mechanical engineering sectors, with particular expertise in medical devices, food and drink, energy and automotive
• Represent you before the EPO in Oppositions and Appeals, working alone or as part of an international litigation team to defend key patents or knock out third party rights
• Provide strategic patent support in relation to portfolio advice, freedom to operate, validity and infringement matters; helping to support new product development, acquisitions and due diligence

Overview & Expertise

Daniel Sizer is a Partner in Marks & Clerk’s London office and is a Chartered (UK) Patent Attorney, European Patent Attorney and UPC Representative.

Daniel has significant experience across a wide range of facets of IP prosecution and management. He has particular expertise in the medical device, food and beverage, energy and automotive sectors.

Daniel’s practice focuses on high-value matters such as inter-partes procedures before the EPO, due diligence and freedom to operate and invalidity. Daniel regularly represents his clients before the Opposition Division and Appeal Boards of the EPO and has been commended by clients for the quality of his results. He works closely with in-house advisors to ensure that Opposition and Appeal strategy is closely aligned with commercial considerations. Daniel has also represented a client on a case that was referred to and decided on, in favour of his client, by the Enlarged Board of Appeal. As part of this work, he frequently works as part of a multi-jurisdictional opposition and litigation team.

A significant part of Daniel’s practice involves supporting his clients with freedom to operate (FTO), invalidity and infringement matters to identify, quantify and mitigate against risks posed by third parties. Daniel has overseen multi-jurisdictional freedom to operate projects for clients in the medical device, consumer goods, and product handing sector.

Daniel is a Partner in the Engineering team and sits on Marks & Clerk’s Energy Group Leadership committee, which provides oversight and steering for the UK business’ growth activities in this area. Daniel is also the oversight Partner for Marks & Clerk’s Training Academy. He is therefore responsible for managing Marks & Clerk’s in-house training programme for Marks & Clerk’s trainees.

Daniel graduated from the University of Cambridge with a first-class degree and Master's in Mechanical Engineering before joining Marks & Clerk. Daniel speaks English.

Client Work & Case Experience

• Medical and consumer device sector – providing patent drafting, prosecution and strategy strategic advice and advocacy before the EPO for market leaders in the electronic cigarette, medical device and Femtech sectors.
• Food and beverage sector – managing patent portfolios and opposition strategy in the fields of packaging, product handling and delivery for a global brewery and global food and drink company.
• Meril Life Sciences – managing Oppositions before the EPO for Meril Life Sciences in the field of prosthetic heart valve crimpers.