[citation needed] The 1569 Act of Union inaugurating the Polish-Lithuanian Commonwealth confirmed that, as previously in the Grand Duchy of Lithuania, Lithuanian families of dynastic origin remained entitled to use the title Prince.
A decree issued in 1401 by Jogaila, King of Poland and Grand Duke of Lithuania, confirms the right of Prince Michał Giedroyć vel.
Ratybor (baptized c.1387) to the arms Hippocentaurus "as used by his illustrious grandfather" Ginwill (2nd Duke of Giedrojcie and candidate to the grand ducal office of Lithuania).
But the earliest surviving illustrated Giedroyć armorial charge is a rose, on seals attached to state documents of 1431-4.
At the English College of Arms, the arms of Michal Giedroyc (born 1929, 16th generation in the Line of Bartłomiej) include both the rose and the centaur (called a sagittary in English heraldry) blazoned as follows: Per fess Or and Gules in chief a Rose Gules barbed and seeded proper and in base a Sagittary trippant to the dexter the head facing to the sinister his tail a serpent facing to the dexter holding in the hands a Bow with arrow drawn and set towards the head of the serpent all Or.