* Borrower --- broker, hedge fund, etc. seeking to borrow securities held by a fund (mutual fund, say)
* Lender --- the fund
* Collateral --- when a fund lends securities, the borrower is required to provide collateral as protection to the lender in cae the securities are not returned or need to be replaced
* Investment Yield --- the invetment return from re-investing the cash collateral pledged by the borrower against the borrowed securities
* Rebate Rate --- the interest paid (rebated) by a lender back to the borrower of the securities. The rate is negotiated based on supply/demand of the loaned security; when a security has minimal borrower demand, a higher rebate is paid to the borrower (reducing profits to the lender); when a security has an abundance of demand the rebate is lower, or even negative, which indicates the lender is receiving a rate from the borrower (increasing profits to the lender).
* Total Spread --- Investment Yield - Rebate Rate (for cash collateral), it can be viewed as a proxy for total profitability of the loan transaction
* Fees --- the premium paid by a borrower to the lender when a loan transaction is collateralized with non-cash, such as Treasuries or Agencies
* General Collateral ("GC") --- Easily borrowed (abundant) securities; typically providing minimal returns to the lender due to limited demand and higher Rebate Rates (lower borrowing cost)
* Warm Securities --- securities with a moderate demand from borrowers; typically providding moderate returns to lenders
* Special Securities --- securities that have limitted supply, producing high borrower demand; typically providing low or negative Rebate Rate and higher returns to lenders (higher borrowing costs)
