Marriage augmentation of honour granted in 1536 by King Henry VIII to his 3rd wife Jane Seymour: Or, on a pile gules between six fleurs-de-lys azure three lions passant guardant or. Regranted by her son King Edward VI by letters patent dated 10 August 1547 to his uncle en:Edward Seymour, 1st Duke of Somerset, Lord Protector, eldest brother of Jane Seymour. The Seymour marriage augmentation arms are a difference of the royal arms, showing "Plantagenet" on the pile and "France", with tinctures inverted, on the fieldReferences:
Archives in Seymour Papers, Longleat House, Wiltshire: "Patent to (Edward Seymour, 1st Duke of Somerset), to bear the coat of augmentation granted to Queen Jane Seymour, 10 August 1547. Box I.10.f.119"[1]
Burke, Bernard (1884). The General Armory of England, Scotland, Ireland, and Wales; Comprising a Registry of Armorial Bearings from the Earliest to the Present Time. London: Harrison &amp; sons. p. 914.
Debrett, John (1836). Debrett's Complete Peerage of Great Britain, the United Kingdom and Ireland. London: J. G. &amp; F. Rivington. p. 159.
MacCulloch, Diarmaid (2018). Thomas Cromwell: A Life. London: Allen Lane ISBN 9780141967660. pp. 427–8, plate 9.Some sources state that the augmented arms were also granted at the time of Jane Seymour's marriage, to her eldest brother Edward Seymour, who was at that time created 
Viscount Beauchamp, (later Earl of Hertford and Duke of Somerset) (MacCulloch, Diarmaid. (2018). Thomas Cromwell: A Life. London: Allen Lane. ISBN 9780141967660, pp. 427-8, plate 9)

Coat of arms of Edward Seymour, Viscount Beauchamp, 1536
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