The regulator said concerns had been raised about governance issues at Catz Club, which trades as Schoolfriendetc, in September 2007.
A commission statement said the concerns related to "internal financial controls and overdue accounts".
The commission said it had not yet opened a formal inquiry and stressed that the investigations were not linked to political donations.
The charity's most recently submitted accounts, for the year ending September 2006, showed income of £850,000 and expenditure of £4.25m. It had debts of £3.5m to trade creditors and loans totalling more than £3m from chair Anthony Mitchell and Futurebuilders.
Last week, shadow charities minister Greg Clark questioned the judgement of the trustees, who were forced to take back a £7,500 Labour donation.
Catz Club declined to comment.