Starting in 2017, the German Ministry of Defence had conceived a replacement for the G36. Several companies attempted to provide a replacement, including H&K, who had submitted both the HK416 and HK433, but lost to the MK 556, by C. G. Haenel, with the decision being finalised on the 14 September 2020. H&K complained about "unrealistic demands", and claimed that there was a lack of fairness in the proceedings, a notion shared by another participant, SIG Sauer. The first MK 556 rifles were expected to begin production by the end of October 2020, where it was slated to eventually phase out the G36. However, a possible patent law violation by Haenel concerning their rifle's magazine forced the German government to withdraw its commission.