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HMRC internal manual

International Manual

The attribution of capital to foreign banking permanent establishments in the UK: The approach in determining an adjustment to funding costs - STEP 3: determining the equity capital: Tier 3 capital

Tier 3 capital is used to support trading book activities and essentially consists of short-term subordinated debt. Very little Tier 3 capital appears to be issued in practice, but any such debt will be “loan capital” for the purposes of CTA09/Part 2/Chapter 4.