Knock for knock excess question

[Elderly]

This morning I was involved in a very minor incident with another vehicle with no damage to my car.
He says it was my fault and I say it is his, but I can't see any insurance company being able to apportion/prove blame on one party or the other.
We have exchanged details.

I have no intention of making a claim, but he ( or I should say his father, as it was his father's car or insurance ) might make a claim for damage to his car.

Assuming that he claims for damage to his car and the insurance companies agree knock for knock
and I'm not claiming, will any portion of my excess (50%?) be used towards his damage?

[Elderly]

Thanks for the info.

I've put my insurance co. on notice that there might be a claim from a T.P.

If there is a claim, my insurers will look at the 'facts' and make a judgement as to the percentage of blame.