Should Maria de Sa keep its surname, as Maria de Sá does? #857

sa is a credential, and unlike ba it is not marked as possibly a name, so the unaccented spelling of the Portuguese surname Sá reads as a suffix: Maria de Sa gives last de, suffix Sa, and Joao Sa gives no last name. Sá has 1,600 US Census bearers and 110+ Wikidata family bearers (2026-10-23). In tse-donors, 255 pairs of one person's names that differ only by accents split on SÁ / SA (#843).

Measured with sa marked as a possible name, the mixed-case names are fixed: Maria de Sa gives last de Sa, and Joao Sa gives last Sa. Names in capitals are not: MARIA DE SA and ANA SILVA SA still read SA as the suffix, because a word in capitals with words to spare reads as a credential (rule S6). Nearly all the tse names are in capitals, so the flag alone would fix few of the 255. John Smith SA, John Smith S.A. and John Smith, SA keep suffix SA.

sa was left unmarked because it is both a title and a credential, and decisions/C8 recorded the flag turning John Smith, MS into a title. That no longer happens for John Smith, SA, so the question is whether the mixed-case fix is worth the flag, and whether a capitals name like MARIA DE SA is a separate question.