You still can't take it with you. But some executives have arranged for the next best thing: huge corporate payouts to their heirs if they die in office.

Take Eugene Isenberg, the 78-year-old chief executive of Nabors Industries Ltd. If Mr. Isenberg died tomorrow, Nabors would owe his estate a "severance" payment of at least $263.6 million, company filings show. That's more than the first-quarter earnings at the Houston oil-service company.

Dozens...