De Clercq & Partners



Practice area

IP STARS Reviews


De Clercq & Partners is one of the leading Belgian firms for patent protection and portfolio management work, particularly in the fields of biotechnology and chemistry. The firm has several experienced European patent attorneys such as Ann De Clercq, Sakina Bounaga, and Liesbet Paemen. The firm is also recommended for trade mark work. Joost Muylle is the key contact for trade mark instructions.



"They provide a timely, customer-oriented service."

"They are responsive and well organised."

"De Clercq & Partners is our SPOC for all trademark and patent filings and dossiers across the globe. They are responsive, fast and efficient."

"They are prepared to think strategically and provide clear advice."

"They are very accurate and fast in their response and really think together with the business on the best approach."

"They deliver results fast, provide a full scope with potential fall-back routes and are available when needed."

"They are extremely professional. In particular, they send the right reminders at the right time and they are very efficient in translating my input into draft PCT demands or responses to Office Actions. Deadlines are always met and I do not worry about missing any as De Clercq & Partners efficiently manages the communication to receive my input in due course when this is required."

"They produce very decent work and clear (no-nonsense) communication."

"We appreciate their expertise on the science and full understanding of the technology we develop."

"They are hands-on, pragmatic, and very professional, providing great expertise for a reasonable price."

"We value our long relationship with them."

"We appreciate the quality, proximity and availability."

"We especially appreciate their strong communication."

"They provided very good advice before the redaction and they do not 'push' to file patents when they think that the prior art is blocking as it is not always the case with other offices."

"They are pleasant and efficient."

"We value their expertise and willingness to 'go the extra mile'."

"Their responses are very quick and they are a very flexible and solution-oriented firm."

2022 client testimonials 

"De Clercq & Partners knows our technology very well and is experienced in European patent prosecution."

"They provide timely follow-up of deadlines and advice on prosecution matters." 

"Their quality is exceptional as well as their knowledge of our technology."

"They are extremely efficient." 

"Clear communication at every level of the firm."

"We chose De Clercq & Partners because we needed a highly regarded IP firm located in Belgium with experience in mechanical and life sciences innovation."

"High-quality work, very responsive and reasonable fees."

2021 client testimonials

A biotechnology client said: “The firm is among the top three in Belgium in the biotech sector. [They are] professional and always available.”

“They manage our European patent portfolio and have a strong understanding of the technology,” another biotech client noted.

2019 client testimonials

“[The] quality is very high in the field of patent prosecution,” says a client.

Another client said the firm’s practitioners are “very professional, client oriented, and good people to work with”.

The firm impressed a client with its “speed and knowledge in opposition and oral proceedings”. The client added: “They are well trained and friendly.”

“[The firm] is fantastic and I will continue working with them, even if I leave the company,” a client explained.

A client commended the firm for its “well-organised back office”, “collaborative way of working”, and “forward-thinking patent drafting”.

“De Clercq & Partners maintains a consistent, high standard of work,” another client said.


The firm was involved in several EPO proceedings, representing companies such as Cosucra Groupe Warcoing, Vandemoortele Lipids, Total Research & Technology Feluy and The Broad Institute. In 2020, it hired European patent attorneys Robrecht Dumarey and Lieve Coenegrachts. 

Trade mark

Case studies show filing and trade mark office proceedings work for clients in a range of industries. Clients include Antleron, Alken-Maes NV, De Linde, AOC Aliancys and The Groom BV.