Please refer to Q&A 607 of “Answers to questions on the Final report on the ITS on the templates for the submission of information to the supervisory authorities (CP-14-052)”.

In the case of unlimited sum insured, the contracts should be reported in S.21.02 (if considering the below instructions they are the biggest) and in template S.21.03, considering the following:
-    For the reporting of the ‘Sum insured’ undertakings should use an estimation of the expected possible loss (calculated using the same methods as used for the calculation of the premium, which should reflect the actual risk exposure).
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Specifically for S.21.03:
-    In case of unlimited exposures, these contracts need to be reported in the last bracket. We expect that this contracts are reported in the last bracket but that the “Total sum insured” is calculated using the same methods as used for the calculation of the premium, which should reflect the actual risk exposure;
-    We clarify that even if this amount is lower that the bracket reference this should be reported in the last bracket. Narrative reporting should supplement the quantitative information;
-    Please note that where possible (where undertaking use undertaking specific brackets) only those risks with unlimited sum insured should be allocated to last bracket. Meaning that when this is the case, undertakings should choose their bracket size so that no policies with a known sum insured falls into the last bracket.

As stated in instructions for S.21.03.C0020/R0010-R0210:
“For policies where there is no Sum Insured defined in the policy the undertaking should do their own estimations or use default values.
The option chosen needs to be used consistently over the reporting periods, unless the distribution of claims changes significantly.