How do I check whether I retained copyright for a figure in a paper from ten years ago? I have been contacted by a student who wants to reproduce a figure from a paper of mine in Phil Trans R Soc B (this one, in case it's pertinent) in their thesis. The paper itself is apparently not under a CCAL (I normally choose this option if it is available, but it looks like it wasn't for this one), and I can't find any record of the copyright agreement at the time - the manuscript was submitted about ten years ago. 

The journal has a link to the Copyright Clearance Centre for requesting permission for reuse; I ran the form myself and it seems that the student can pay a fee to get permission from the journal to reproduce my figure. That is not my question.

My question is, how to I check whether I transferred copyright for the figure at the time? If I didn't I can presumably just send him the submission version of the figure.

I tried searching the Royal Soc website but it seems surprisingly difficult to find this (which I have noticed before with Elsevier; I think they'd rather we assume they always get the copyright).

Related: How to legally re-use images in paper and still continue to use and distribute them in slides? (but this is about a situation where the copyright transfer status is known).
Unless the paper is open access, the publisher usually holds the copyright. This can be seen in the imprint on the first page of the paper. If it says "(c) the publisher" then the publisher holds the copyright, while if it says "(c) the authors" then it's the authors who do.

In the case of your paper though, the Royal Society's plagiarism, copyright and intellectual property page says


  Authors of non open-access papers retain the copyright, but grant the Royal Society the exclusive right to edit, adapt, translate, publish, reproduce, distribute and display the article in printed, electronic or any other medium and format.


I'm no lawyer, but I take this to mean that while you cannot distribute the paper in its final form, you can distribute a single figure.