The logo should be on the home page and pages that solicit deposit accounts.
If it is on those deposit pages, and they could appear in the portal page, it would not be necessary to show it twice, once on the page in the main-frame and once on the top or left frame (as is a common setup). Also, you are assured of disclosure if the user selects "open in new window". In this case they get only the selected page, no frames. If only the frame had the logo disclosure, that could be a problem.
If it is on the portal page and a page can be brought up in the main-frame of the portal that has (as an example) stocks, I could see a problem there. I have heard differing opinions, but would lean more towards a cleaner separation of insured and non-insured products. So I agree with you.
I would lean towards having it on the individual pages that could be accessed instead of on a master frame that could add confusion.
One other area to look at is your Internet banking demo page. Is "Member FDIC" there? That is an advertisement for accounts. Often it is omitted from there and it shouldn't be.
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Andy Zavoina
Opinions stated are not necessarily that of my employer.