Identifying which shares were transferred to married partner

If I buy shares of the same company in multiple transactions and then transfer some of them to my married partner, how do I identify which shares I transferred? Is there any general identification rule (like "first in first out") or I need to find the particular shares that were transferred in my transaction records?

Hi David,
As they are all in the same company you would treat this as a S104 holding and  just use an average price.
Shares and Capital Gains Tax (Self Assessment helpsheet HS284).
Thank you. 

Thank you! So just to clarify, a transfer to married spouse is also considered disposals and is a subject to "Same day" and "Bed & Breakfast" matching rules, is it correct? Which means it doesn't necessary need to be matched only against S104 holding. Kind regards, David

Hi
At the time of transfer no. It is only if/when the spouse then decides to sell that it is a disposal.