To refuse to send income tax history to agency?

[NextOneb]

I have been in my current job for 4.5 years.
The job I had before my current one, was with a company that went into administration.

I have secured a new job with an agency as a contractor. I am shocked at how tedious the reference process has been.

Not only has my current employer provided a satisfactory reference, as has my university and I also obtained a character reference as requested. The agency is insisting I get a reference from the company that went into administration and they have asked me to share with them my income tax and pension payment history from HMRC’s website. Aibu to not provide this, as it shows my salary history? This is more information I have been asked to disclose than, I had to share to get security clearance in a previous role…

I feel my salary history is something the agency may use to try to negotiate contractor salaries on my behalf and ie pay me less, whilst paying themselves more. I just don’t feel comfortable with this level of information. However Aibu here?

If it's proof of employment delete/black out the figures ... or give them P60s and do the same. Or bank statements with figures covered up.

Ahh thanks everyone! Work has been manic today but I have next week off so will probably give myself some more time to decide what I want to do. I had an interview earlier today and I progressed to the next stage, so I might just suck up sending my income tax un-redacted with the view for leaving for a better role!

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