The NCA argued that Arshid Khan, 51, and Asif Khan, 43, originally from Burnley, had profited from supplying Class A drugs over a considerable period of time.
Some of these profits (£636,525) had been used to acquire land and property in West Yorkshire between 2005 and 2018.
The land and property was held in the names of family members, or limited companies controlled by family members.
In April 2018, the NCA issued a claim for civil recovery in the High Court over these three properties and two pieces of land.
The extended family whose names were listed where properties were registered, or who had control of the companies holding the properties, were entered into a settlement which saw the NCA recover £530,000 in cash without the need for a trial.
There was no finding of criminal wrongdoing against the extended family members.
Andy Lewis, Head of Civil Recovery at the NCA, said: "It is a common criminal tactic to try and hide profits using family members identities.
"This settlement should act as a clear warning that the NCA will use all the available powers to pursue such profits or the assets purchased with them, even when a period of time has passed.
"These funds will now be returned to the public purse and used to support further work tackling organized crime."
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