Thailand’s richest man Charoen Sirivadhanabhakdi distributed stakes in holding firms which control about 66% of Thai Beverage Pcl to his five children, though stopped short of handing over full control of the drinks giant.

The scions of the octogenarian billionaire put into effect a shareholders’ agreement which will confer on their father “the authority to manage and make all decisions in respect of the business and assets” of the entity, according to filings to the Singapore exchange late Monday.

That move means that a key question over who will ultimately take over Charoen’s sprawling business empire remains unanswered, as a succession plan gathers pace. The tycoon is worth an estimated $10.9 billion, according to the the Bloomberg Billionaires Index. A cornerstone of that is Thai Beverage, the maker of Chang beer, which also operates distilleries across Scotland.

The share transfer is part of a longer term shift in the holdings of the patriarch and his late wife Khunying Wanna Sirivadhanabhakdi as succession beckons. The company didn’t immediately respond to a request for comment.

Thapana Sirivadhanabhakdi, his elder son, is ThaiBev’s current Chief Executive Officer. The restructuring means he will share the family’s controlling stake in the firm with his brother, Panote Sirivadhanabhakdi, who’s the CEO of Singapore-listed property developer Frasers Property Ltd, as well as three sisters – Atinant Bijananda, Wallapa Traisorat and Thapanee Techajareonvikul.

Thapanee is the CEO of Berli Jucker Pcl – a conglomerate with interests including grocery retailer Big C, while Wallapa helms Asset World Corp., a Thailand-focused hospitality firm.