We request permission to use methanogen isolates, particularly isolate D5, in a new research programme funded by the Bezos Earth Fund, through the Global Methane Hub, titled “Deciphering the Requirements for an Efficacious Antibody Mediated Anti-Methanogen Response in the Rumen”. This is being carried out in conjunction with Professor John Hammond of the Pirbright Institute in the UK. More details are provided in the accompanying letter (attached).