In the usual repo transaction, a firm sells assets to another company, while agreeing to buy them back at a slightly higher price after a short period. It can be for as little as overnightIn other words, this is a short-term loan. The assets are the collateral.
Because the term is so short, there is little risk the collateral will lose its value. The lender or firm making the purchase thus takes a low interest rate.
With repo transactions, a borrower can get funds more cheaply than it could with one long-term loan that would put the lender at greater risk.
Under standard accounting rules, ordinary repos are considered loans, and the assets remain on the firm's books, But if a borrower could find a way that removes the assets from its books, often just before the end of the quarterly financial reporting period, the move temporarily makes the firm's debt levels appear lower than they really are.
This procedure has its standing in a rule FAS 140, approved by the Financial Accounting Standards Board in 2000. It modified earlier rules that allow companies to "securitize" debts such as mortgages, bundling them into packages and selling bond-like shares to investors.
FAS 140 allowed the pooled securities to be moved off the issuing firm's balance sheet, protecting investors who bought the securities in case the issuer later ran into trouble or bankruptcy.
Because repurchase agreements were loans and not sales, they did not fit the rule's intent. The rule contained a provision saying the assets involved would remain on the firm's books so long as it was agreed that the buy-back be for a price between 98% and 102% of what had been received for them. If the repurchase price fell outside that, the transaction would be treated as a sale, and not a loan.
In the case of the Lehman Brothers repos, it is alleged that the firm agreed to buy the assets back for 105% of their sales price and booked the transaction as a sale, to remove the assets from the books. The Lehman transactions were made under the advice of their counsel.