Yes, they do but they are rare at the moment.

Using seatspy.com I can see that there are no dates in the next 12 months where there's First available for 2 people but there's 1 seat available on August 20th 2021 from LAX to LHR. There's one seat available on the return on Aug 21, Jan 11, Jan 25, Feb 15 and Feb 22. Slim pickings.

For SFO there are 2 seats in First on August 7th 2021 and that's it with no availability for 2 on the return at all. There are three dates for 1 person on the way over and hardly anything back.

By contrast, there's currently a decent amount of CW availability for 2 people on both routes.