According to § 667 2nd alt. BGB, the agent is obliged to give his client everything that he obtains from the business. According to a decision of the Ninth Senate of April 11, 2006 ( 9 AZR 500/05 ), this principle also applies to employment relationships, although employees do not work for free within the meaning of Section 662 of the German Civil Code (BGB). The obligation to surrender applies to all benefits that have been granted to the employee by a third party, not only on occasion, but due to an internal connection with the business being conducted. The principle applies that the person for whose account and therefore at whose expense another conducts business is entitled to all the benefits of the transaction. The employee is therefore also obliged to use the bonus miles acquired from a frequent flyer program for business-related flights paid for by the employer in the interests of the employer. For the employer’s claim for surrender in accordance with Section 667 2nd Alt. BGB is irrelevant whether the airline wants to give the bonus miles exclusively to the frequent flyer. The obligation to disclose also includes the personal benefits intended for the agent. Otherwise, the agent would be allowed to keep any bribes given to him.