A trade union in charge of matters regarding the affected company is allowed to approach employees of this company with advertising and information via their business email addresses. This also applies if the employer has prohibited the use of email addresses for private purposes. The decision of a union to approach employees in this way is part of its protected freedom of action pursuant to Article 9 (3) first sentence German Constitution. The employer's protected property right pursuant to Article 14 (1) German Constitution, and his/her right to the established and carried on trade or business establishment pursuant to Article 2 (1) German Constitution have to take second place to the trade union's freedom of action, as long as the sending of emails does not interfere with the ordinary course of business or cause noticeable economic strains attributable to the union.