Q&AThe 17th Baron, William Crawford Miller of Pittenweem, was Baron of Pittenweem from 1978 to 2011. He died without issue and the Barony of Pittenweem was conveyed to Claes Zangenberg, who became the 18th Baron. The new Baron was confirmed by a Letter Patent from the Lord Lyon in 2016 as “Claes Zangenberg, Baron of Pittenweem”. The current Baroness is Yasar Zangenberg.
The title is certainly not extinct. It was confirmed by a Crown Charter of Confirmation in 1869 and the title of the current baron has been confirmed by a Warrant for Letter Patent issued by The Court of The Lord Lyon. The misunderstanding most likely originates from a mistake in the book "The Peerage of England, Scotland and Ireland; or The Ancient and Present State of the Nobility" from 1790, which accidentally listed the title as extinct. At that time, the title was used by the eldest sons of the Earls of Kellie, the title first having been acquired by the 1st Earl of Kellie in 1614 and then (after passing briefly to the Crown) again re-granted to the 3rd Earl of Kellie and any of "his male heirs and assignees" in 1672 (a transcript of the charter is available online here).
An encyclopedia article on the history of the Lordship and Barony of Pittenweem can be found here.