No, credit card cashbacks are not reportable income. Thankfully, neither are frequent flyer miles. (They used to be. What a royal pain!) OTOH, it sounds like Kavanaugh’s credit card balances were being carried, not paid off every month. The detailed instructions indicate that credit card debt over $10k must be reported.
DH has to fill out those disclosure forms annually. These are the basic instructions, though different levels of appointees/career civil service, etc. have varying levels of disclosure. https://www.oge.gov/web/278eguide.nsf/Chapters/OGE%20Form%20278e?opendocument
For DH and me, most of what actually gets reported is actually my assets/income (over $1.000); honoraria over $200, assets related to employment or business that have more than $1,000 in value (my two sewing machines) or produced more than $200 in income (so yeah, I report my $300/year in fabric art sales); my IRA and 401k accounts, our savings (both jointly held as well as separately) and when our kids lived at home, their UGMA/529 accounts. The assets get reported in bands of amounts (i.e., $1-10,000, $10,001-$25,000, etc.) so that what comes out in a public report sounds like a wide range (and makes you think something’s off). So, if I had $10,002 in each of my four mutual funds, the range reported would be $40,008 to $100,000. Amplify that across an IRA, a 401(k) and a couple of savings accounts and the disparity becomes significant.
DH’s fed gov’t retirement accounts aren’t included because those who are reviewing those reports can get that info directly from the source. Ditto his salary.
The report is mainly looking at whether DH has outside income, what funds/stocks we are invested in, what trades we may have engaged in (any transaction >$1,000), and if any of those represent a potential conflict of interest. There are industries we personally choose to stay away from as a matter of course, and we only own one stock, purchased in 1985, many years before he was a fed EE. Everything else is in money market and mutual funds. They also ask if DH received any gifts or travel reimbursements from outside sources. The gift limit is tiny – <$25, IIRC, and means that in most cases, if he attends a professional conference, he can’t accept free meals. Sometimes DH is asked to speak at international conferences and the sponsor pays his transportation (but not food or hotel). Those trips are cleared by his agency’s ethics office before he agrees to accept the engagement.
The form also asks for liabilities, excluding personal vehicles where the vehicle is the security & primary residence. A primary residence must be reported if it generates rental income. We do not have to report cash, MM accounts, or Treasury instruments. Home equity loans/HELOCs must reported if there is a balance. Student loans and co-signed loans (with some exceptions) are reportable. DH’s report is pretty straightforward. We’re plain vanilla. If one has lots of real estate, LLCs, outside positions, commodities trading, options, etc., it can get much more interesting.