Jan primarily represents large, listed corporates as well as international investors, with a focus on the defence industry. Over the last decade, he has been involved in some of the most complex transactions and public takeovers in the German market, often in the centre of public attention. 

He also advises on all areas of corporate law, stock corporation law and capital markets law, particularly with respect to general meetings, capital and financing measures, squeeze-outs, IPOs, de-listings as well as other complex structural measures and stakeholder issues. Another focus of his work is advising executive boards and supervisory boards with respect to liability and compensation as well as corporate governance, in particular in stock corporations and European companies (Societas Europaea). Jan represents clients in legal disputes with minority shareholders and in relation to inquiries by the German Federal Financial Supervisory Authority (Bundesanstalt für Finanzdienstleistungsaufsicht, BaFin). 

Jan regularly publishes in the specialist press on corporate and stock corporation law Topics.