You're in a controversial area because you're acting as though it is outdoor (like a billboard) and exempted, but it's technically indoors and can be seen from the outside. Advertisements may be indoor signs even though they can be seen by consumers from outside. An example is a banner hung inside the bank on a wall or a chalk sign that can also be seen thru the glass door.
Disclosure requirements can depend on what you'll have on the ad. What will these say or is that known yet? You want it to be an outdoor sign without it being outdoors, but it may be able to only be read from outside making it as good as an outdoor sign. It's splitting hairs either way. My fear is that it is splitting hairs to mislead and be complete only by having the consumer come in during open hours and ask, instead of providing clearly information that may be required.
https://www.bankersonline.com/regulations/12-1030-008 Here is our editor's note:
The exception for indoor signs in section (e)(2) originally applied only to signs designed and placed to be seen and read primarily by customers inside the bank's branch office. The Economic Growth and Regulatory Paperwork Burden Reduction Act of 1996 amended ยง 263(c) of the Truth in Savings Act to eliminate that limitation, and it was removed from the regulation effective 9/24/1998. Here is an excerpt from the 9/29/1998 Federal Register publication of the final rule making that amendment (63 FR 52105): "A further amendment to section 263(c) contained in the 1996 Act expands the exemption for signs on the premises of the depository institution. All signs inside the premises of an institution are now exempt from certain advertising disclosures (including signs that are intended to be viewed from outside the premises). Accordingly, the reference in Sec. 230.8(e) [now Sec. 1030.8(e)] to signs that face outside the premises and the corresponding provision in the official staff commentary, comment 8(e)(2)(I)-2, are deleted."