It has come to our attention that several NHS Trusts in carrying out the IR35 assessment have been conflating the term "Office Holder" with permanent posts. The argument we have had reported to us is along the lines "you are covering a permanent position therefore you are an office holder".

HMRC makes it clear in their guidance who/what an office holder is. However, there are HMRC employees on the advice and help line who do not adhere to this definition. This could imply that they are acting unlawfully.

How to make a Freedom of Information Act Request (UK)

A quick FOIA request to an example Trust showed that that they do not have any office holders "In line with the definition provided by HMRC".

If you encounter this argument, a FOI request via this website should help clear this up.