I believe the $7B refers to the difference between the realized value and the value of the securities sold AT THE BEGINNING OF THE PERIOD, i.e. as of 3/31,

No, that won't be it. The line item says quite explicitly it is the figure for "securities sold during the period" under the heading Second Quarter 2024. So, it includes only those things sold after March 31 and up to June 30.

Also in Note 7, p. 11: "Equity securities gains and losses include unrealized gains and losses from changes in fair values during the period on equity securities we still own...." So, were there some sizeable (net) unrealized losses?

No, that won't be the explanation. That line item I'm looking at explicitly says it's the figure for "securities sold during the period", so that line item does not include the unrealized gain/loss, which is the line above, "Change in unrealized investment gains (losses) during the period on securities held at the end of the period".

Still scratching my head.

The footnote talks specifically about taxable profit from sales during the quarter. So the only thing I can think of is that a taxable/GAAP-reportable [in that quarter] distinction is at play. I can't think of any reason that would happen, though. Or a gigantic offsetting realized loss on other "securities sold during the period" that makes no sense to me.

Jim