The Bundesarbeitsgericht (BAG, Federal Labour Court) tightened the requirements for proving receipt of legally relevant letters in its judgment of May 7, 2026 (case no. 2 AZR 184/25). Employers cannot readily rely on the posting receipt and electronically reproduced delivery receipt for a registered letter delivered to the mailbox when serving important letters. If proof of receipt is not successful, this may be to the employer’s detriment in unfair dismissal proceedings.
Employee challenges dismissal on grounds of illness
The decision of the Bundesarbeitsgericht was based on unfair dismissal proceedings in which an employee who had been employed since May 2015 challenged an ordinary dismissal by his employer on grounds of illness. More than ten employees worked full-time at the business, meaning that the Kündigungsschutzgesetz (KSchG, German Protection Against Dismissal Act) applied.
In the three years before the dismissal was issued, the employee had repeatedly been unfit for work due to illness. In the period from November 28, 2020 to November 27, 2021, absences relevant to the prognosis amounted to 40 working days; in the following one-year period, they amounted to 75 working days; and in the period from November 28, 2022 to November 27, 2023, they amounted to a further 37 working days.
Invitation to company integration management (bEM)
The employer had already invited the employee several times to participate in company integration management (bEM). A corresponding procedure had been carried out in August 2022. A further invitation from April 2023, however, remained unanswered.
After the employee had again recorded significant absences due to illness in the period from May 3 to October 6, 2023, the employer sent a further invitation to bEM on October 11, 2023. The letter was sent as a registered letter delivered to the mailbox. However, the employee disputed having received the invitation. No further bEM took place.
After hearing the staff council, the employer terminated the employment relationship by letter dated December 15, 2023, with ordinary notice effective June 30, 2024.
Arbeitsgericht upholds unfair dismissal claim
The employee filed an unfair dismissal claim in due time. He argued that the dismissal was socially unjustified. In particular, he claimed that there was no sufficiently negative health prognosis; furthermore, the dismissal was disproportionate because no proper bEM had been carried out. He had not received the invitation from October 2023.
By contrast, the employer relied on the posting receipt, shipment tracking and a reproduction of the delivery receipt of Deutsche Post AG. In its view, these showed that the invitation had been delivered on October 14, 2023. In the employer’s opinion, the documents submitted established prima facie evidence of receipt.
The Arbeitsgericht (Labour Court) upheld the unfair dismissal claim. The Landesarbeitsgericht Hamburg (Hamburg Regional Labour Court) dismissed the employer’s appeal after examining the named postal delivery worker as a witness. With its appeal on points of law to the Bundesarbeitsgericht, the employer continued to pursue its aim of having the dismissal declared effective.
BAG dismisses appeal on points of law
The Bundesarbeitsgericht dismissed the employer’s appeal on points of law by judgment of May 7, 2026 – 2 AZR 184/25. The dismissal on grounds of illness was socially unjustified and therefore legally invalid.
Two related issues are at the center of the decision: proof of receipt of an invitation to bEM and the employer’s burden of substantiation regarding the proportionality of a dismissal on grounds of illness where a required bEM was not carried out.
No prima facie evidence of receipt in the scan procedure used
The BAG rejected prima facie evidence that the invitation to bEM had actually been received by the employee.
According to the findings of the Landesarbeitsgericht Hamburg (judgment of July 14, 2025 – 4 SLa 26/24), the registered letters delivered to the mailbox were served in the relevant Deutsche Post AG procedure using a scanner. The delivery worker first recorded the barcode of the item. He then signed on the input field of the device, thereby completing the electronic documentation process. Only after that did he place the letter in the recipient’s mailbox. The data were transmitted directly to Deutsche Post AG’s tracking system.
In the BAG’s view, this procedure does not establish a typical course of events that allows the conclusion, with sufficiently high probability, that the item was actually placed in the correct mailbox.
Timing of the documentation decisive
The decisive difference compared with the delivery procedure addressed in earlier decisions of the Bundesgerichtshof (BGH, Federal Court of Justice) lies in the timing of the documentation. In the procedure underlying those decisions, the peel-off label used for identification was removed from the item immediately before it was placed in the mailbox and affixed to a delivery receipt. The delivery worker then confirmed delivery by signature and date. The documentation thus related to an item that had already been placed in the mailbox.
In 2023, the Bundesgerichtshof had still affirmed prima facie evidence of receipt for registered letters delivered to the mailbox if the posting receipt and a reproduction of the delivery receipt were submitted. The difference from this so-called peel-off procedure is that, in the scan procedure, the signature is already provided before the item is placed in the mailbox. The evidentiary position has therefore shifted not because of a changed legal assessment, but because of the change in the delivery procedure.
In the scan procedure relevant here, by contrast, the documentation process was completed before the item was actually placed in the mailbox. After signing on the scanner, the delivery worker still had to place the item into the mailbox. It was therefore not excluded that, after the electronic confirmation, he was distracted or held up and, contrary to the documentation already created, did not properly place the item in the mailbox.
No sufficiently high probability
The BAG clarified that the electronic recording may allow conclusions that the delivery worker was at the intended delivery location and that the item had reached that location. However, it does not establish a sufficiently high probability that the letter subsequently actually reached the correct mailbox.
The combination of posting receipt, shipment tracking and reproduced delivery receipt also led to no other result.
The central statement is therefore: In the Deutsche Post scan procedure examined here, the submission of these documents does not establish prima facie evidence of actual receipt of a registered letter delivered to the mailbox.
This does not mean that every registered letter delivered to the mailbox is generally unsuitable as proof of receipt. Rather, the decisive factors are the specific delivery procedure used and the question of whether the documentation permits a sufficiently reliable conclusion that the item was actually placed in the mailbox.
According to its own statements, Deutsche Post has already changed its delivery process: after scanning, the delivery worker now additionally confirms placement digitally in the scanner by signature and confirmation of insertion. As a result, prima facie evidence could again be considered in the future.
Alternatively, delivery methods that can be proven independently of the postal procedure may also be examined: in particular, personal handover—ideally in the presence of a witness—as well as delivery by a messenger or courier service may be considered.
Examination of the postal delivery worker did not prove receipt
The employer was also unable to prove receipt of the invitation by examining the delivery worker as a witness.
The postal employee examined as a witness had no specific recollection of the delivery in dispute. He could neither confirm that the signature on the reproduction of the delivery receipt was his, nor reliably describe that he always followed a specific procedure when delivering registered letters to mailboxes.
The Landesarbeitsgericht was therefore entitled to assess the testimony as inconclusive. The BAG found no error in this assessment of the evidence that was material for purposes of the appeal on points of law.
Receipt of the invitation to bEM therefore remained unproven.
Renewed invitation to bEM despite earlier non-response
The BAG also reaffirmed that, as a rule, the employer must again take the initiative to carry out bEM if the statutory requirements are met and the employee again has substantial periods of incapacity for work after an earlier refusal or non-response.
Under § 167(2) sentence 1 SGB IX (Ninth Book of the German Social Code), bEM must be offered if employees are continuously or repeatedly unfit for work for more than six weeks within one year.
If an employee has not accepted an earlier invitation, the employer’s obligation does not cease permanently. If the employee again falls ill to the corresponding extent, his willingness to participate may have changed. The employer must therefore generally make another attempt; it should therefore have invited the employee again to carry out bEM.
Since the employer could not prove receipt of the invitation dated October 11, 2023, it could not be established that it had properly complied with its duty to take the initiative.
Examine milder measures before dismissal on grounds of illness
A dismissal on grounds of illness requires, among other things, that no reasonable milder measure is available that could avoid the dismissal or reduce future absences. Possible measures include adapting the existing workplace, continued employment in another suitable position, or medical rehabilitation measures.
bEM is not itself a milder means compared with dismissal. However, it serves to identify and develop such alternatives. § 167(2) SGB IX specifies the principle of proportionality in this respect.
If the employer omits a required bEM, it is subject to an expanded burden of substantiation in unfair dismissal proceedings. It must then specifically set out on its own initiative and, where necessary, prove that even a proper bEM could not have identified suitable measures to prevent further periods of incapacity for work or at least significantly reduce them.
In the present case, this proof was not successful.
Dismissal disproportionate
Since the employer had neither proven receipt of the renewed invitation nor sufficiently substantiated the objective futility of a further bEM, the dismissal was disproportionate.
The other issues in dispute between the parties, in particular the proper hearing of the staff council, were no longer decisive.
Registered letters delivered to the mailbox are not reliable proof of receipt
The BAG makes clear that a posting receipt and an electronically reproduced delivery receipt do not automatically establish prima facie evidence of receipt.
For practice, this means a departure from the assumption that a registered letter delivered to the mailbox is always sufficient proof of receipt if the corresponding shipment documents are submitted.
The decision directly concerns the specific scan procedure examined. It does not state that a registered letter delivered to the mailbox would under no circumstances be suitable for proving receipt. Nor can it be inferred from the decision that receipt could never be proven by other evidence.
However, employers must expect that merely submitting the usual shipment documents will not be sufficient if receipt is disputed in a substantiated manner. Subsequent examination of the delivery worker as a witness will also not necessarily help, particularly if the delivery worker has no specific recollection of the process.
Consequences for receipt of notices of termination and other declarations
The decision is significant beyond the specific bEM context. The principles on prima facie evidence concern the question of whether receipt of a document can be deemed proven on the basis of a typical course of events.
This may become relevant in particular for notices of termination, warnings, setting of deadlines and other declarations requiring receipt, but also for time-bound declarations in commercial dealings, such as reminders, revocations or termination of a contract, the legal effects of which under § 130 BGB (German Civil Code) require receipt by the recipient.
However, distinctions must be made: the BAG ruled directly on proof of receipt of an invitation to bEM, not on the effectiveness of a notice of termination that itself was served by registered letter delivered to the mailbox. The transferability of the considerations to other documents therefore depends on the specific delivery procedure and the circumstances of the individual case.
For legally relevant letters, reliance should therefore not be placed solely on electronic shipment tracking. The following additional measures may be considered:
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personal handover against a meaningful acknowledgment of receipt;
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delivery by a messenger who knows the content of the letter and can document placement in the correct mailbox;
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another form of service that enables robust proof of actual receipt.
Which option is preferable in an individual case depends, among other things, on urgency, costs, the evidentiary objective and the statutory requirements applicable to the declaration in question. Especially in the case of dismissals, service should therefore be treated as an independent component of legal risk management.
Significance of the judgment
In its judgment of May 7, 2026 – 2 AZR 184/25 – the Bundesarbeitsgericht combines two statements that are central to employment law practice.
First, in the specific scan procedure of Deutsche Post AG examined, the posting receipt, shipment tracking and reproduced delivery receipt do not establish prima facie evidence that a registered letter delivered to the mailbox actually reached the correct mailbox.
Second, omitting a required bEM can cause a dismissal on grounds of illness to fail if the employer does not substantiate that even a proper bEM could not have identified milder means of avoiding the dismissal.
MTR Legal Rechtsanwälte advises companies on employment law issues. Further information can be found at Legal advice in employment law.
