Its a buy borrow die strategy. You take loans and refi them to be larger and larger until you die, when you do, the cost basis is reset (so if your cost basis was 1,000,000, but you investments are now worth 20,000,000, your cost basis becomes an untaxable 20,000,000) this new "stepped up" untaxable money (in investments) is used to pay off the debt by selling some assets, lets say 5,000,000 in debt covered by selling (untaxable) investments. This would be for someone with a handful of millions of dollars, I can only imagine what it is like for someone who has hundreds of billions in assets...
Its a buy borrow die strategy. You take loans and refi them to be larger and larger until you die, when you do, the cost basis is reset (so if your cost basis was 1,000,000, but you investments are now worth 20,000,000, your cost basis becomes an untaxable 20,000,000) this new "stepped up" untaxable money (in investments) is used to pay off the debt by selling some assets, lets say 5,000,000 in debt covered by selling (untaxable) investments. This would be for someone with a handful of millions of dollars, I can only imagine what it is like for someone who has hundreds of billions in assets...