Idiom: require someone to do something --> C

doesn't the verb require "require" a subjunctive mood?

Only if it is uncertain whether the one who is required to do something, actually does it.
Here, "require" is a rule by the SEC that everyone has to follow.

Subjunctive is used only when there is uncertainty. The rule 13(d) of the SEC is a fact. When a sentence reflects uncertainty in the form of a 'request' or 'hope' then one could use a subjunctive verb.

Suspicion confirmed; it is the absence of "that" that makes it not subjunctive... One definitely to remember for D-day.

More details:
https://gmat-grammar.blocked/2006/0 ... verbs.html

Example:
The Forton-Dodd bill requires that a bank disclose to their customers how long they will delay access to funds from deposited checks.
A. that a bank disclose to their customers how long they will delay access to funds from deposited checks.
B. a bank to disclose to their customers how long they will delay access to funds from a deposited check.
C. that a bank disclose to its customers how long it will delay access to funds from deposited checks.
D. a bank that it should disclose to its customers how long it will delay access to funds from a deposited check.
E. that banks disclosed to customers how long access to funds from their deposited check is to be delayed.

OE: C

Nice Question.
The verb "Require" can be used as with subjunctive or infinitive.

The general construct of sentences with subjunctive verb is as follows-
(subjective verb) THAT (subject) BE (simple form of verb)
Example : A requires that B disclose his marks.

Since in the question in this discussion does not used"that" after 'requires', we cannot used subjunctive.
So, we are need to use infinitive which makes (C) the correct answer.