Did Alexander Utendal really compose the motet Angelus Domini a23 in A-Wn, HAN Cod. 9814?

The collection HAN Cod. 9814 in the Austrian National Library contains the motet Angelus Domini a23 attributed to the composer Alexander Utendal (after 1530–1581), copied by the scribe Georg Khues (fl.1579–1621) apparently as a gift for Emperor Matthias (1557–1619) on his 60th birthday on 24 February 1617. Although the very unusual scoring of the composition, with 23 voices in four choirs, immediately raises doubts, the attribution of the work to Utendal has not been questioned in the literature so far. After a thorough compositional and textual analysis, the present study will suggest that Angelus Domini was not written by Utendal, but by a representative of the Venetian polychoral school around 1600. Furthermore, the compositional device of two low voices in unison in tutti sections, used in Angelus Dominus a23, is taken as a reference point to place the motet in the vicinity of similar works known to have been written by composers active at the court of Ferdinand II (1578–1637) in Graz.