King Maha Vajiralongkorn inherited one of the world's great fortunes when he ascended the throne in October following the death of his father Bhumibol Adulyadej who ruled for seven decades.
Thailand's monarchy is shielded from both criticism and scrutiny by a draconian lese majeste law and does not declare its wealth.
But analysts say the Chakris are one of the world's wealthiest royal dynasties, with estimates varying between $30-60 billion.
Most of this wealth is controlled by the opaque Crown Property Bureau (CPB), a vast portfolio that includes massive property ownership and investments in major companies.
On Sunday the Royal Gazette published a new law governing the CPB that was passed by the junta's rubber-stamp legislature last week and went into effect on Monday.
The main change gives Vajiralongkorn power to appoint all members of the committee that oversees the CPB.
Under the previous law, the committee's chairman was the finance minister, a move meant to ensure some semblance of government oversight.
That requirement has now been removed, allowing Vajiralongkorn free rein to appoint who he likes to head the committee.
Is is the first time that law has been changed in 69 years.
On paper the monarchy has little constitutional power.
A 'network monarchy'
But under Bhumibol's long and charismatic reign it came to wield huge political and economic clout behind the scenes.
Academics often dub Thailand a "network monarchy" in which major aristocratic families, businesses and state bureaucracies, including the military, all benefit from royal patronage.
The country's first succession in 70 years stirred anxiety among powerbrokers about how the new monarch would manage those complex relationships.
Since Bhumibol's death, a series of legal changes have been made which analysts say strengthens Vajiralongkorn's power.
At the request of the new king's office the junta waved through constitutional amendments earlier this year.
Among these was a provision allowing the king to travel overseas without having to appoint a regent in his stead, and an end to the need for all royal decrees to be countersigned by a government official.
Vajiralongkorn also took direct control of five state agencies overseeing royal affairs and palace security that were previously under government or military control.
In the past Thailand has responded to published estimates of the monarchy's wealth by pointing to the previous law governing the CPB, arguing that it was the government which had ultimate say over the royal wealth.