From: Rabbi Moshe Sofer
To: Rabbi Aharon Kutna
The Chasam Sofer rules that the Chevra Bikur Cholim acquired the 500-gold-piece bequest outright at the testator's death, and the elder brother's voluntary annual payments to the Chevra must be treated as compensation for lost investment income rather than deductions from the principal, leaving the full principal still owed. The elder brother must also account to the younger orphans for retaining their share of the Chevra's funds in the family business, and if they dispute his claim that this served their interests, he must swear to that effect or compensate them proportionally.
Source: Shu"t Chasam Sofer CM §157