What disclosure does not show
Disclosure reveals transactions, not motives, and its coverage has edges. Organisations that spend on politics while not having political activity as their primary purpose may not be required to disclose donors in the same way a political committee is, which is the origin of the term "dark money".
Timing also limits usefulness. Because reports are periodic, spending late in a campaign may not appear publicly until after voting, though separate 24- and 48-hour reporting requirements apply to independent expenditures close to an election.
