I will try to get the recording soon and put it up, in the meantime I will summarize the points I discussed in Shiur, and the conclusions:
PART A:
1) If Reuven lets Shimon use his Credit Card to purchase merchandise for $5,000 and Shimon agrees to pay back before the 'due date,' then it's all fine.
2) Halachically, Shimon has no connection to the Bank, and it is as if there are two loans here, one loan from the Non-Jew to the Jew (Bank to Reuven), and one loan from the Jew to the Jew (Reuven to Shimon).
3) If Shimon wants to pay back in installments, and pay the interest, it is not allowed, unless Reuven & Shimon do a 'Heter Isska' between them (with all the risks involved).
4) If Shimon agreed to pay back in full on time, but he didn't, and as a result Reuven got hit with late fees and interest - There is debate what the Halacha is. According to some opinions - Reuven cannot charge Shimon for the interest, because it is as if he is charging interest on their loan (Taz). According to others - Reuven can demand the payment from Shimon as any person who causes a damage, and it's a 'Knas' (Maharshdam). And according to others - Reuven can't demand the payment, but Shimon should pay the interest as a means of appeasing Reuven for the damage caused.
PART B:
1) If Shimon asks Reuven to lend him his Credit Card and Reuven agrees without any convincing, then Reuven can keep the miles without a problem.
2) If Shimon convinces Reuven to lend him his Credit Card by saying that he will get x-amount of miles for the purchase, it may be a an issue, similar to the prohibition 'Derabanan' of making the lender feel good with extra niceties, etc.
3) If Reuven needs to meet a spending threshold for bonus points and can't do so on his own, and Shimon persuades him to let him use the CC so he gets the bonus - this is probably prohibited, as above. However, Reuven can offer Shimon the CC to meet the spending threshold.
4) Can Shimon ask Reuven for a share of the miles? (WILL BE DISCUSSED IN NEXT SHIUR - SEE BELOW)
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THIS SUNDAY, MARCH 15TH @ 10:00AM
I will be giving the next class, discussing the following:
1) If Reuven let Shimon use the CC to earn the sign-up bonus, and Reuven would not be able to earn it without Shimon, can Shimon claim a share of the miles?
2) If your boss paid for your business trip, can he claim the miles?
3) And More...
Date: Sunday March 15th
Time: 10:00am
Location: Mayan Yisroel of Flatbush, 3315 Avenue N, Brooklyn NY