{"id":10942,"date":"2026-08-26T16:24:08","date_gmt":"2026-08-26T16:24:08","guid":{"rendered":"https:\/\/www.dhenne-avocats.fr\/contentieux-des-brevets\/defense-accusation-contrefacon\/"},"modified":"2026-08-26T16:26:33","modified_gmt":"2026-08-26T16:26:33","slug":"defense-accusation-contrefacon","status":"publish","type":"page","link":"https:\/\/www.dhenne-avocats.fr\/en\/contentieux-des-brevets\/defense-accusation-contrefacon\/","title":{"rendered":"Sued for patent infringement: organising the defence"},"content":{"rendered":"<p><strong>Les premiers jours comptent double.<\/strong> Une mise en demeure ou une assignation en contrefa\u00e7on n&rsquo;est jamais anodine : gel des preuves, information des \u00e9quipes commerciales, revue des contrats d&rsquo;approvisionnement et de distribution, notification \u00e0 l&rsquo;assureur le cas \u00e9ch\u00e9ant. Avant toute r\u00e9ponse au demandeur, il faut cartographier le risque r\u00e9el : validit\u00e9 du brevet invoqu\u00e9, lecture de ses revendications, exposition des produits en cause, cha\u00eene de responsabilit\u00e9 (fabricant, importateur, distributeur).<\/p>\n<h2>Les axes de d\u00e9fense<\/h2>\n<p>Ils se combinent : contestation de la contrefa\u00e7on (analyse revendication par revendication, description des diff\u00e9rences techniques), demande reconventionnelle en <a href=\"\/en\/contentieux-des-brevets\/action-en-nullite-brevet\/\">nullit\u00e9 du brevet<\/a> (art. L. 613-25 CPI), contestation des op\u00e9rations de <a href=\"\/en\/fields-of-expertise\/counterfeit-seizure-attorney\/\">actual seizure for infringement<\/a> (r\u00e9f\u00e9r\u00e9-r\u00e9tractation, mainlev\u00e9e, cantonnement du s\u00e9questre, protection des <a href=\"\/en\/fields-of-expertise\/trade-secrets-attorney\/\">secrets d&rsquo;affaires<\/a> saisis), moyens de proc\u00e9dure, et, lorsque l&rsquo;exploitation est ancienne, possession personnelle ant\u00e9rieure (art. L. 613-7 CPI). En amont de tout litige, l&rsquo;entreprise qui veut s\u00e9curiser un lancement peut aussi prendre l&rsquo;initiative d&rsquo;une action en d\u00e9claration de non-contrefa\u00e7on (art. L. 615-9 CPI).<\/p>\n<h2>N\u00e9gocier sans se d\u00e9couvrir<\/h2>\n<p>La plupart des contentieux de brevets se terminent par un accord. Encore faut-il n\u00e9gocier au bon moment, sur la base d&rsquo;un rapport de forces document\u00e9 \u2014 solidit\u00e9 du brevet, exposition r\u00e9elle, co\u00fbt du proc\u00e8s pour chaque partie \u2014 et sans concession probatoire irr\u00e9versible. Nous conduisons ces n\u00e9gociations en parall\u00e8le de la d\u00e9fense, jamais \u00e0 sa place.<\/p>\n<p><strong>Assignation ou saisie re\u00e7ue ? <a href=\"\/en\/french-patent-litigator-contact-us\/\">Appelez-nous aujourd&rsquo;hui<\/a> \u2014 <a href=\"tel:+33171606146\">+33 1 71 60 61 46<\/a>.<\/strong><\/p>\n<p>See also: <a href=\"\/en\/contentieux-des-brevets\/\">Patent litigation<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>Les premiers jours comptent double. Une mise en demeure ou une assignation en contrefa\u00e7on n&rsquo;est jamais anodine : gel des preuves, information des \u00e9quipes commerciales, revue des contrats d&rsquo;approvisionnement et de distribution, notification \u00e0 l&rsquo;assureur le cas \u00e9ch\u00e9ant. Avant toute r\u00e9ponse au demandeur, il faut cartographier le risque r\u00e9el : validit\u00e9 du brevet invoqu\u00e9, lecture [&hellip;]<\/p>\n","protected":false},"author":4,"featured_media":0,"parent":10937,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-10942","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.2 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Assign\u00e9 en contrefa\u00e7on de brevet ? 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