10 Sen - Omar Ali Saifuddin III

Brunei's 1967 coinage series was issued in the final years of Omar Ali Saifuddin III's reign — he abdicated in October 1967 in favor of his son Hassanal Bolkiah, making this among the last issues to carry his effigy. The abdication was voluntary and largely unprecedented in the region, driven in part by the Sultan's desire to redirect political pressure following Brunei's decision not to join the Malaysian Federation in 1963.

That 1963 refusal, grounded in disputes over oil revenue sharing and political representation, is the direct reason Brunei retained its own currency infrastructure at all.