Alls engi verðr Inga
undir sólar grundu
bǫðvar hvatr né betri
brœðr landreki œðri.
Alls engi landreki, hvatr bǫðvar, verðr œðri né betri brœðr Inga undir grundu sólar.
No land-ruler at all, brave in battle, will become more distinguished or better than Ingi’s brother [= Sigurðr munnr] beneath the ground of the sun [SKY/HEAVEN].
case: dat.