Debt to a Broker Regarding the Release of Debts

My father is an elderly man abroad, and it's difficult to explain to him that he needs to make a Prozbul. I manage his accounts, he has no debts to Jews, and the bank and pension company are definitely owned by non-Jews. However, he is a broker, and there are clients who have not yet paid him. Should I make an effort to explain to him to make a Prozbul?

Debts to a broker are not canceled, but some hold that they are considered like loans and are canceled. Try to explain to him that there is an issue of Prozbul and that he should simply appoint you as his agent, and you will arrange everything for him.

We learned in the Tractate Shevi'it (Chapter 10, Mishnah 1) that the Sabbatical year cancels a loan, whether documented or not. "Store credit" is not canceled, but if it was made into a loan, it is canceled. "Wages" are not canceled, but if they were made into a loan, they are canceled. In explaining why "store credit" and "wages" are not canceled, two approaches are given. The first approach, which is the opinion of most early authorities, see Tosafot Gittin 18a, Tosafot Ketubot 55a, and others, is that only a loan is canceled, but a debt incurred through sale or labor, or in any other way, is not canceled. The second approach is the opinion of Rambam, as explained by Beit Yosef (Choshen Mishpat, Siman 67) and Kesef Mishneh (Chapter 9, Laws of Shemittah and Yovel, Halacha 11), and this is also the ruling in Sema (Siman 67, Sif Katan 26) and Shulchan Aruch HaRav (Laws of Loans, Paragraph 39), that not only a debt incurred by a loan is canceled, but any debt is canceled, even if incurred through sale or labor, or in any other way. However, the reason "store credit" and "wages" are not canceled is because, in their time, it was customary to buy on credit for a long period, and only when a very large amount accumulated, they would pay. Therefore, at the end of the Sabbatical year, it is not yet a debt ready for collection, and thus it is not canceled. Similarly, regarding "wages," it was customary not to pay immediately but only after a large amount accumulated, and at the end of the Sabbatical year, it is not yet a debt ready for collection. There is a practical difference between these two approaches in our time, where it is usually customary to pay after a short time, such as a monthly salary paid to an employee. According to most early authorities, it is not canceled because it is not a debt due to a "loan," while according to Rambam, it is canceled. Similarly, "store credit" in our time, where it is customary to pay once a month, according to most early authorities, it is not canceled (if it was not made into a loan) because it is included in the category of "store credit," but according to Rambam, it is canceled because "store credit" mentioned in the Mishnah is only in a case where at the end of the Sabbatical year, the debt is not ready for collection. However, even in the case of "store credit," if it was made into a loan, the debt is canceled [and this is the intention of the aforementioned Mishnah "if it was made into a loan, it is canceled"]. What is "making it into a loan," we find many opinions on this, and we will detail some of them: the opinion of Rosh (Tractate Gittin, Chapter 7, Siman 17), that it is setting a time for repayment of the debt before Rosh Hashanah, and the opinion of Mordechai (Tractate Shevuot, page 8 according to Mordechai), if he wrote the summary of the entire debt together.