Clause 8-6 was new in 2016.
The clause prescribes that the insurance is subsidiary to another insurance that the co-assured third party has taken out. Consequently, the insurer shall only be liable to the extent that the co-assured third party has not obtained cover under the other insurance, cf. Cl. 2-6, sub-clause 2. If the other insurance also has a subsidiary provision, Cl. 2-6, sub-clause 1, shall prevail, cf. Cl. 2-6, sub-clause 3, with the effect that the co-assured third party is free to claim under any of the two insurances.